REQUEST FOR PROPOSAL
18/24/30 MVA 138 kV to 13.09 kV 3φ Power Transformers with LTC
WEATHERFORD MUNICIPAL UTILITY SYSTEM
SECTION I - SCOPE
A.
The Weatherford Municipal Utility System invites qualified and responsible applicants to submit a written
proposal for the furnishing of three 18/24/30 MVA 138 kV to 13.09 kV three phase substation power
transformers with on-load tap changers designed and equipped per the attached technical specifications.
B. It is the intent of this request to have the successful applicant enter into an agreement to furnish, ship,
unload, install, and assemble each of the power transformers to one of the substations owned by the
Weatherford Municipal Utility System, Weatherford TX, 76086.
C.
The first of the transformers is to be delivered mid-March, 2016. The timing of the remaining
transformer deliveries is to be the subject of discussion between the Utility and the Applicant, but is to
be completed no later than the fall of 2017.
SECTION II - DEFINITIONS OF TERMS
The following terms as used throughout this document and the attachments are defined as follows:
A.
Utility - The Weatherford Municipal Utility System, a public utility enterprise, wholly-owned by the
City of Weatherford, Texas.
B.
Department – The Electric Department, that portion of the Weatherford Municipal Utility System
which owns and maintains the electric distribution system and substations.
C.
Director - The Director of the Weatherford Municipal Utility System and/or his/her designated
representatives and/or agents.
D.
Applicant - Is interchangeable with and synonymous with the terms "BIDDER", "INSTALLER", "PROVIDER",
each term of which is used to mean the person(s) who are submitting a written proposal to provide the
specified services.
E.
R.F.P. - A "Request for Proposal" which details the services required by the City and the respective
terms and conditions.
A. Proposal - A formal written document and any supporting information submitted by the "APPLICANT"
offering to furnish the equipment and provide the required services.
1
SECTION III - APPLICATION AND AWARD
A.
The "APPLICANT" shall pick up a Request for Proposal and/or detailed specification from the
following location:
Finance Department
303 Palo Pinto
Weatherford, Texas 76086
Telephone No.: 817-598-4232
B.
The applicant's completed "Proposal" and all required forms and supporting documents must be
submitted on or before 2:00 pm, Tuesday August 18th, 2015. The completed proposal shall be
submitted to:
Finance Department
303 Palo Pinto
Weatherford, Texas 76086
Telephone No.: 817-598-4232
1.
All RFP’s will be publicly opened and respondent’s names read aloud at 2:00 pm, Tuesday
th
August 18 , 2015, at City Hall Council Chambers, 303 Palo Pinto for the Substation Power
Transformers Proposals.
2.
All applications must be submitted in a sealed envelope clearly marked with the words
PROPOSAL 2015-010; SUBSTATION POWER TRANSFORMERS .
3.
th
Any proposals received after 2:00 pm, Tuesday August 18 , 2015 will be considered late and
non-conforming and returned to the applicant unopened.
C.
The Utility reserves the right to reject any and/or all proposals and/or any portion of a single proposal
with or without cause.
D.
The Director will evaluate the conforming proposals for compliance with the terms and conditions. The
Utility will approve the purchase of at least three identical transformers subject to the terms and
conditions listed herein.
E.
The service agreement shall be awarded on a total bid basis for a single vendor, at the best value to the
Utility, to provide Substation Power Transformers at its various sites.
F.
Upon completion of the approval process and approval of the agreement terms and conditions by the
City of Weatherford Legal Department, the agreement will be signed by the successful applicant and the
Utility.
SECTION IV - APPLICATIONS AND QUALIFICATIONS
2
Each applicant which submits a written proposal must meet the minimum requirements as detailed in the
RFP and shall include in his or her proposal the following documents; which will be used as the evaluation
criteria in selecting the most qualified applicant(s):
A.
A complete resume including experience as it relates to this service with reference names and phone
numbers.
B.
A complete technical description of the proposed substation power transformers.
C.
A statement outlining the assumptions and criteria used to design the proposed substation power
transformers to be supplied to the Utility.
D.
A statement outlining the shipping, erection, assembly, filling, and testing of the transformer to be
provided under contract.
E.
A statement of the proposed pricing structure for the provision of these services.
F.
Before submitting proposals, each bidder will be held responsible for having examined the Utility
substation environments and satisfied itself as to the existing conditions under which he or she will be
obligated to deliver, unload, assemble, and fill the transformer that will in any manner affect his or her
services under the agreement. No allowances shall be made in this connection on behalf of the bidder
for any error or negligence on his or her part.
G.
A completed copy of the attached Conflict of Interest form.
SECTION V - GENERAL GUIDELINES
The successful Provider will be required to enter into a written agreement with the Utility incorporating the
proposal and this agreement.
SECTION VI - SPECIFICATIONS
The attached TECHNICAL SPECIFICATION FOR A 138/13.09KV, 18/24/30 MVA THREE PHASE POWER
TRANSFORMER shall be incorporated by reference.
3
In WITNESS WHEREOF, the parties have caused this AGREEMENT to be duly executed, in multiple
counterparts, intending to be bound thereby on this the _____________ day of
______________, _________.
WEATHERFORD MUNICIPAL UTILTITY SYSTEM
Printed Name:
Title:
Signature:
Date:
SUBSTATION POWER TRANSFORMER PROVIDER
Company:
Printed Name:
Title:
Signature:
Date:
4
138 /13.09 KV 18/24/30 MVA TRANSFORMER
WEATHERFORD ELECTRIC
WEATHERFORD MUNICIPAL UTILITY SYSTEM
WEATHERFORD, TEXAS
TECHNICAL SPECIFICATION
FOR A
138/13.09KV, 18/24/30 MVA
THREE PHASE POWER TRANSFORMER
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TABLE OF CONTENTS1.0 SCOPE AND CLASSIFICATION ---------------------------------------------------------------------------------------- 4
1.1
1.2
SCOPE -------------------------------------------------------------------------------------------------------------------------- 4
CLASSIFICATION-------------------------------------------------------------------------------------------------------------- 4
2.0 APPLICABLE STANDARDS ---------------------------------------------------------------------------------------------- 4
2.1
2.2
PRIORITY OF STANDARDS --------------------------------------------------------------------------------------------------- 4
REGULATIONS ---------------------------------------------------------------------------------------------------------------- 4
3.0 FUNCTIONAL AND SUPPLIER REQUIREMENTS ---------------------------------------------------------------- 4
3.1
3.2
FUNCTIONAL REQUIREMENTS ---------------------------------------------------------------------------------------------- 4
SUPPLIER REQUIREMENTS -------------------------------------------------------------------------------------------------- 4
4.0 PERFORMANCE REQUIREMENTS ----------------------------------------------------------------------------------- 5
4.1
4.2
4.3
4.4
4.5
4.6
4.7
RATINGS ----------------------------------------------------------------------------------------------------------------------- 5
LOADING ---------------------------------------------------------------------------------------------------------------------- 5
IMPEDANCE ------------------------------------------------------------------------------------------------------------------- 6
LOSSES ------------------------------------------------------------------------------------------------------------------------- 6
SHORT CIRCUIT REQUIREMENTS------------------------------------------------------------------------------------------- 7
AUDIBLE SOUND LEVEL ---------------------------------------------------------------------------------------------------- 7
LIQUID LEVEL ---------------------------------------------------------------------------------------------------------------- 7
5.0 ACCESSORIES AND ADDITIONAL REQUIREMENTS ---------------------------------------------------------- 8
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
5.10
5.11
5.12
5.13
5.14
5.15
5.16
5.17
5.18
GENERAL ---------------------------------------------------------------------------------------------------------------------- 8
MATERIAL ------------------------------------------------------------------------------------------------------------------- 10
BUSHINGS ------------------------------------------------------------------------------------------------------------------- 11
NAMEPLATE REQUIREMENTS -------------------------------------------------------------------------------------------- 11
CURRENT TRANSFORMERS ----------------------------------------------------------------------------------------------- 12
SURGE ARRESTERS -------------------------------------------------------------------------------------------------------- 12
DE-ENERGIZED TAP CHANGER ------------------------------------------------------------------------------------------- 12
ON LOAD TAP CHANGER (LTC) ----------------------------------------------------------------------------------------- 13
INDICATING DEVICES ------------------------------------------------------------------------------------------------------ 16
COOLING EQUIPMENT ----------------------------------------------------------------------------------------------------- 17
OIL PRESERVATION SYSTEM --------------------------------------------------------------------------------------------- 18
CONTROL CABINETS ------------------------------------------------------------------------------------------------------- 18
AUXILIARY AND CONTROL POWER-------------------------------------------------------------------------------------- 20
GROUNDING----------------------------------------------------------------------------------------------------------------- 20
HANDLING ------------------------------------------------------------------------------------------------------------------ 21
VACUUM FILLING ---------------------------------------------------------------------------------------------------------- 21
PAINT REQUIREMENTS ---------------------------------------------------------------------------------------------------- 21
INSULATING OIL ------------------------------------------------------------------------------------------------------------ 22
6.0 INSPECTION AND TEST REQUIREMENTS ---------------------------------------------------------------------- 22
6.1
6.2
6.3
6.4
OBSERVATION RIGHTS ---------------------------------------------------------------------------------------------------- 22
ROUTINE TESTS ------------------------------------------------------------------------------------------------------------ 23
ADDITIONAL TESTS -------------------------------------------------------------------------------------------------------- 23
TEST REPORTS -------------------------------------------------------------------------------------------------------------- 26
7.0 OTHER REQUIREMENTS ---------------------------------------------------------------------------------------------- 27
7.1
7.2
7.3
7.4
7.5
7.6
DRAWINGS ------------------------------------------------------------------------------------------------------------------ 27
DESIGN REVIEW ------------------------------------------------------------------------------------------------------------ 29
SHIPPING AND RECEIVING ------------------------------------------------------------------------------------------------ 30
INSTALLATION -------------------------------------------------------------------------------------------------------------- 35
WARRANTY ----------------------------------------------------------------------------------------------------------------- 35
MATERIAL SAFETY DATA SHEETS AND WASTE REDUCTION NOTIFICATION ------------------------------------- 35
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7.7
7.8
7.9
SERVICE BULLETINS ------------------------------------------------------------------------------------------------------- 36
LOSS SUBMITTAL REQUIREMENTS -------------------------------------------------------------------------------------- 36
FALL PROTECTION --------------------------------------------------------------------------------------------------------- 36
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1.0
SCOPE AND CLASSIFICATION
1.1
Scope
This specification sets forth the minimum requirements for operating characteristics and safety
features of a 138/13.09kV power transformer.
1.2
2.0
Classification
1.2.1
The transformer shall be 18/24/30 MVA three phase, 138 kV delta - 13.09kV wye, 65°
C temperature rise, with an on load tap changer (LTC).
1.2.2
The transformer will be installed at an altitude less than 3300 feet and subjected to an
annual ambient temperature variance of -30° C to +45° C.
1.2.3
The transformer shall be designed for continuous operation at rated capacity at the
specified altitude and ambient temperature range.
1.2.4
The transformer shall be capable of cold starting in a -30 Deg C ambient with the core
and coil also at -30 Deg C.
APPLICABLE STANDARDS
2.1
2.2
Priority of Standards
2.1.1
Equipment supplied in accordance with this specification shall comply with applicable
provisions of the latest NEMA, IEEE, ANSI/IEEE, ASTM, NESC, NEC, and ANSI
standards relating to power transformers. In case of conflict between any of the
standards mentioned in this specification and the contents of this document, the
Weatherford Municipal Utility System specification shall govern.
2.1.2
The manufacturer shall inform WEATHERFORD MUNICIPAL UTILITY SYSTEM
of all instances where there are conflicts between WEATHERFORD MUNICIPAL
UTILITY SYSTEM specifications and the applicable standards.
Regulations
2.2.1
3.0
The manufacturer, joint venture partners, and all sub-contractors shall comply with the
United States of America Federal Acquisition Regulations when purchasing material
for use in our transformers.
FUNCTIONAL AND SUPPLIER REQUIREMENTS
3.1
Functional Requirements
3.1.1 The transformer will be used in an electric utility distribution substation to feed 12.47kV,
3 phase, 4 wire, grounded wye, with solidly grounded neutral circuits from the bus
from separately furnished outdoor circuit breakers. The transformer will be used in a
step-down application from the 138kV transmission system to the 12.47 kV
distribution system.
3.2
Supplier Requirements
3.2.1 To preclude difficulties with overseas shipping and with WEATHERFORD
MUNICIPAL UTILITY SYSTEM personnel access to the factory and to the design
engineering team, the engineering and manufacturing location shall be restricted to
North America.
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3.2.2 The manufacturer shall be able to demonstrate no less than ten (10) years experience
successfully building and testing power transformers of the size, complexity, and
quality outlined in this specification.
3.2.3 The manufacturer shall be prepared to openly discuss with the WEATHERFORD
MUNICIPAL UTILITY SYSTEM design consultant the manufacturers test floor
failures and remedies over previous ten (10) year period.
3.2.4 The manufacturer shall be able to provide to WEATHERFORD MUNICIPAL UTILITY
SYSTEM a list of installed transformers in the region which may be readily inspected
by WEATHERFORD MUNICIPAL UTILITY SYSTEM personnel, and appropriate
contacts within the Utility owning the installed transformers.
3.2.5 The manufacturer shall own or have an active alliance with a qualified transformer repair
facility within the continental United States trained and equipped to repair the
transformer outlined within this specification.
4.0
PERFORMANCE REQUIREMENTS
4.1
Ratings
4.1.1
Frequency
60 Hz
4.1.2
Phase
3
4.1.3
Class
ONAN/ONAF/ONAF
4.1.4
Voltage
High (HV)
Low (LV)
4.1.5
138,000 (± 5%, DETC) Volts Delta
13,090 (± 10%, LTC) Volts Grounded Wye
Capacity (at all LTC tap positions)
Self-Cooled
Forced-cooled
Forced-cooled
4.1.6
18 MVA
24 MVA
30 MVA
BIL
HV
LV
Neutral
4.1.7
550kV
110kV
110kV
Temperature Rises
Maximum Average Winding Rise
Maximum Hot Spot Rise (Windings and Leads)
Maximum Top Oil Rise
4.2
65° C
80° C
65° C
Loading
4.2.1
The continuous loading shall be as follows:
Duty
Continuous
Continuous
4.2.2
Terminal
HV
LV
MVA
18/24/30
18/24/30
Winding Temp. Rise by Resistance
65°C
65°C
The transformer and all auxiliaries shall be capable of carrying overloads in accordance
with ANSI/IEEE and this specification. The manufacturer shall demonstrate that all
auxiliaries have adequate overload capability.
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4.3
4.2.3
The transformer and all auxiliaries shall be additionally capable of carrying 125% of
the top nameplate rating for a period of 12 continuous hours. This 12-hour emergency
loading period shall commence after the transformer has been fully loaded for 6 hours,
and the top oil temperature has stabilized at 95° C, which assumes a 30° C ambient
temperature. During the 12 hour emergency loading period the ambient temperature
shall be 40° C, the maximum top oil temperature shall be limited to 110° C, the
maximum hot spot temperature shall be limited to 135° C, and the loss-of-life shall be
limited to 0.1%. The PROPOSAL shall provide ultimate overload temperatures and
loss of life calculations.
4.2.4
The neutral lead conductor and the neutral bushing shall be capable of carrying full
load current. The neutral lead conductor and the neutral bushing shall also be capable
of carrying all overloads in accordance with ANSI/IEEE.
4.2.5
The transformer shall be designed and manufactured to allow continuous operation of
all windings at 110% voltage at no-load and at 105% output voltage at full load and 0.8
power factor without gassing.
Impedance
The positive sequence impedance of the transformer shall be 9.92% at the self cooled, base rated
MVA, with the DETC and the LTC on the neutral tap positions. The tolerance on impedance shall
be in accordance with Section 9.2 of ANSI/IEEE.
4.4
Losses
4.4.1
The transformer losses will be used in the evaluation of the Proposals. No-load and
load loss values at the 1 raise LTC position at the self cooled rating shall be supplied
with the PROPOSAL and will be used in the evaluation. If the transformer has a LTC,
which uses variable volts per turn design, the no-load losses shall be guaranteed on the
LTC position having the highest no-load losses.
The manufacturer shall state in the PROPOSAL the DETC and LTC positions with the
highest no-load losses as the guaranteed losses in the case of variable volts per turn design.
The manufacturer shall also submit with the PROPOSAL the auxiliary load at the
maximum forced cooled rating for use in the evaluation. The following life cycle costs will
be used for design purposes and will be evaluated separately when assessing any loss
penalties.
Cost of no-load losses
Cost of load losses
Cost of auxiliary losses
4.4.2
$ 10,820/kW
$ 3,160/kW
$ 3,160/kW
The manufacturer shall submit with the PROPOSAL the percentage maximum total
measurement error for the no-load loss measurement and the load loss measurement
systems. The errors must contain all components of the error including probable
calibration errors and other uncertainties in the measurement system. Certified data for
the loss measurement errors shall be submitted with the PROPOSAL. The data shall be
traceable to the United States National Institute of Standards and Technology or other
equivalent standardization organization. Equivalency will be determined by
WEATHERFORD MUNICIPAL UTILITY SYSTEM using supporting documentation
provided by the manufacturer as part of the PROPOSAL. A system check to insure that
all errors have been properly applied may be required. Failure to submit a loss
measurement system error or the submission of an error that is obviously erroneous
will result in the rejection of the PROPOSAL. The maximum loss measurement error
that is acceptable is ± three (3) percent as per ANSI/IEEE and NIST. Loss
measurement errors greater than ± three (3) percent will result in the rejection of the
manufacturer’s PROPOSAL.
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4.5
4.6
4.4.3
The no-load losses and excitation current at room temperature after impulse tests shall
be used as the guaranteed values and shall not deviate from the no-load losses and
excitation current values measured before impulse tests by more than five (5) percent.
If the difference between the before and after values are greater than five (5) percent,
WEATHERFORD MUNICIPAL UTILITY SYSTEM shall be contacted and a course
of action determined. It is expected that the manufacturer shall determine the cause
and correct any problems that result in deviations in no-load losses and excitation
current that are greater than five (5) percent. WEATHERFORD MUNICIPAL
UTILITY SYSTEM reserves the right to reject the transformer if satisfactory
explanations or corrections are not made.
4.4.4
A transformer which, after factory testing, has actual losses exceeding the guaranteed
losses, as stated in the seller’s PROPOSAL, shall have its selling price reduced. The
amount of reduction will be calculated by determining the actual losses, in kW, above
and beyond the proposed guaranteed kW losses, multiplied by the evaluated cost per
kW. Measured loss values shall be considered separately when assessing loss penalties
(If a loss item is less than the guarantee it cannot be used to offset another loss
component that is higher than the guarantee).
Short Circuit Requirements
4.5.1
The transformer shall be capable of withstanding the mechanical and thermal stresses
produced by external short circuits under the conditions specified in ANSI/IEEE except
allowances for system impedance are not allowed. The available short circuit currents
shall be calculated based on infinite bus source feeding the transformer. In addition, the
source voltage shall be 110% of nominal at nominal DETC tap rating.
4.5.2
The manufacturer shall investigate the different fault conditions (three-phase fault,
single line to ground fault, etc.) for the various combinations of tap positions and
design for the highest stress conditions.
4.5.3
Where applicable, transformer windings shall be designed for free buckling and forces
shall not exceed 65% of the 0.2% yield stress of the conductor. The calculated tensile
stresses in the conductor shall be limited to 80% of the 0.2% yield stress of the copper.
4.5.4
The manufacturer is expected to have adequate model and full size transformer test
data on which to base the acceptance criteria for stresses.
4.5.5
The manufacturer shall provide to WEATHERFORD MUNICIPAL UTILITY
SYSTEM engineer a copy of all criteria and calculations used to calculate the fault
stresses. WEATHERFORD MUNICIPAL UTILITY SYSTEM prefers that this
information be provided in an electronic format that our standard programs can read.
4.5.6
The mechanical stress in the tie plates shall be limited to 65% of the elastic limit for the
steel during short circuit events as well as for stresses incurred during lifting.
Audible Sound Level
The average sound level shall not exceed 68 dB for the ONAN rating and shall not exceed 70 dB for
the maximum forced cooled rating as measured by the procedures outlined in ANSI/IEEE at the
maximum sound level position.
4.7
Liquid Level
4.7.1
The main and LTC compartments shall be designed so that a low-level liquid alarm
will not be activated when the ambient temperature reaches a low of -30 degrees
Celsius with no load connected to the LV bushings.
4.7.2
The main and LTC compartments shall be designed so that oil does not alarm or
overflow the compartments when the ambient temperature reaches 45 degrees Celsius
and the transformer is at 125% of maximum nameplate rating per ANSI standards.
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5.0
ACCESSORIES AND ADDITIONAL REQUIREMENTS
5.1
General
5.1.1
Use 0,1,2,3, for phase designation in lieu of N, A, B, C. Associate phase 1 with H1,
X1, Y1, etc.
5.1.2
All manhole covers and manholes shall be round, with minimum interior manhole
diameter of 24 inches.
5.1.3
The tank cover shall be designed to prevent water from standing on the cover.
5.1.4
All nuts, bolts, and washers used on the transformer shall be non-rust stainless steel or
WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer approved equivalent.
All fasteners shall be metallic or WEATHERFORD MUNICIPAL UTILITY SYSTEM
engineer approved equivalent.
5.1.5
Split or star lock washers shall not be furnished as locking or clamping devices inside
the tank. Double nutting, or other methods approved by WEATHERFORD
MUNICIPAL UTILITY SYSTEM, shall be used for locking or clamping on the lead
support framework.
5.1.6
All gaskets shall be in recessed, machined grooves. All gasket surfaces shall be made
up by flanges that are raised at least ¾ inches above the cover.
5.1.7
All gasket materials shall be of the highest quality and specifically chosen for the
application considering transport shock and vibration, temperature ranges in storage
and in operation, sealed fluids, leakage rates, and ease of repair.
5.1.8
Tank shall be designed so that welds will not be located within 6 inches of the corners.
All tank panel welds with oil on one side shall be welded on both sides. Welders shall
be certified to AWS D1.1.
5.1.9
The tank, including the cover and base, shall be designed such that, after installation,
there will be no permanent deformation caused by shipping or handling.
5.1.10
The serial number and impedance of the transformer shall be permanently stenciled on
the nameplate and provided on construction record drawings.
5.1.11
The maximum allowable burrs on the slit or cut edges of electrical steel used in the
core shall not exceed 0.8 mils. Excessive edge or surface damage during manufacture
may be the basis for the rejection of the core. Manufacturer shall have established
processes to prevent rusting on core edges during the manufacturing process.
5.1.12
The core gaps shall not be greater than 1/16”. Gaps greater than 1/16” must be
justified to WEATHERFORD MUNICIPAL UTILITY SYSTEM as part of their
proposal.
5.1.13
The core induction at 110% voltage at no-load and 105% output voltage at full load
and 0.8 power factor excitation shall not exceed 1.93 Tesla.
5.1.14
The core cross-section shall approximate a circle.
5.1.15
All windings shall be circular, and shall be designed and constructed with full
circumference clamping rings.
5.1.16
HV or LV windings shall be disc or helical only; layered HV or LV windings are not
acceptable.
5.1.17
The use of internal varistors will not be allowed.
5.1.18
All wiring external to the control cabinets shall be run in rigid metallic galvanized
conduit or WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer approved
equivalent. Other accessories, such as thermocouple cable, shall also be run in rigid
metallic galvanized conduit or WEATHERFORD MUNICIPAL UTILITY SYSTEM
engineer approved equivalent. Transformer design shall minimize the use of conduit.
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Any conduit shall be rigidly mounted on standoffs (so it does not lay flat on the
transformer tank or external braces) and shall be painted to match the transformer.
Installation and orientation of Conduit LB’s shall be such that the wire access covers
are positioned for easy access, allowing them to be removed using a standard length
screwdriver. Using the transformer braces or other built-in channel that is subjected to
the transformer heat is not allowed.
5.1.19
The manufacturer shall provide the following spare components for each transformer
purchased without additional cost to WEATHERFORD MUNICIPAL UTILITY
SYSTEM:
One (1) Complete itemized set of gaskets along with one extra set for LTC.
These components shall be delivered with the transformer.
5.1.20
The manufacturer shall state the special tools that are required for the installation and
maintenance of the transformer in the PROPOSAL. In addition, the manufacturer shall
provide any special tools required for the installation and maintenance of the unit
without additional cost to WEATHERFORD MUNICIPAL UTILITY SYSTEM.
5.1.21
Care shall be taken in the design and assembly of the transformers to reduce and to
minimize vibration. The transformer shall be free from any undue or harmful
vibration, which would be detrimental to the operation of the transformer, and any
auxiliaries mounted on the tank or connected to the transformer.
5.1.22
Internal Lead Routing: The lead routing for the active part shall be neat and orderly.
The leads shall be clamped in place to prevent movement during transportation and
operation. The leads shall be supported from the active part support structure with
pressboard clamps; i.e. plastic lead ties, string ties, or fabric tape ties are not
acceptable. Bundles of leads shall be configured to allow free oil flow on lead
surfaces.
5.1.23
The transformer is to be designed to withstand the following minimum shipping
accelerations: 5g longitudinal, 3g vertical, and 1.5g transverse.
5.1.24
The support structure for the lead assemblies shall not be fastened to the upper or lower
winding clamping rings.
5.1.25
The winding temperature shall determine the loading capacity of the transformer. The
loading shall not be limited by any ancillary device such as leads, cables, switches,
bushings, etc.
5.1.26
The lead exit temperatures shall be limited to 3° C higher than the winding hot spot
temperature of the associated winding.
5.1.27
The insulation structure of the transformer is to be designed in consideration of
lightning impulse voltages, switching surge voltages, applied test voltages, and induced
test voltages (enhancement and one hour levels). These voltages shall be used to
determine the electrical stresses in the oil gaps in the major insulation system. The
manufacturer shall analyze the electrical stresses and the conversion from impulse
voltages to the one minute 60 Hz voltage shall be with an impulse ratio of 2.5. The
calculated stresses shall be compared with the Weidmann curve for Partial Discharge
Inception for Degassed Oil. There shall be a minimum of 20% margin between the
curve value and the calculated electrical stresses.
5.1.28
For disk type coils it is required that crossovers be located between key spacer
columns.
5.1.29
The core shall be designed such that the core hot spot temperature is limited to 130° C
with an ambient temperature of 30° C. The excitation conditions shall be the
maximum of the 100% voltage with full load, 110% voltage at no-load, or 105% output
voltage with full load and 0.8 power factor.
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5.1.30
5.2
The minimum pressure on the windings at final pressing after vapor phase processing
is 4 N/mm².
Material
5.2.1
All material used in the construction of the transformer shall be new.
5.2.2
The conductor for all current carrying parts, including windings and leads, shall be
copper or silver bearing copper. Where conductors are spliced, all connections shall be
inspected for quality prior to taping. Joints shall be made by mechanical crimping or
by induction brazing only, soldering or torch brazing will not be accepted. No joints
shall be permitted in draw leads inside bushings.
5.2.3
All material used, or proposed to be used, in the transformer shall be tested, and have
passed the transformer oil compatibility test using the method outlined per ASTM or
WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer approved equivalent.
The test reports shall be available upon request for WEATHERFORD MUNICIPAL
UTILITY SYSTEM inspection at any time during the PROPOSAL or manufacturing
process. Any material found by WEATHERFORD MUNICIPAL UTILITY SYSTEM
inspector which has not had the oil compatibility test performed on it, or that the
manufacturer cannot produce an oil compatibility test report for, shall be tested
immediately at the manufacturer’s expense. If the material fails the oil compatibility
test, WEATHERFORD MUNICIPAL UTILITY SYSTEM will not accept the
transformer until all non-compliant material is replaced.
5.2.4
All material used in the transformer shall be subject by the manufacturer to rigid
quality assurance and control standards. The manufacturer shall have complete
traceability on all material from receiving until final installation in the transformer.
Material tracking and inspection reports shall be made available to WEATHERFORD
MUNICIPAL UTILITY SYSTEM inspector upon request.
5.2.5
The manufacturer shall have conducted an initial vendor inspection and qualifying
audit with ongoing spot checks on all material used in the transformer. Vendor
inspection and audit reports shall be made available to WEATHERFORD
MUNICIPAL UTILITY SYSTEM inspector upon request. Materials found by
WEATHERFORD MUNICIPAL UTILITY SYSTEM inspector to have not been
properly qualified for use by the manufacturer shall, as a general rule, be unacceptable
for use in the transformer. The manufacturer, at the manufacturer’s expense, shall
make arrangements satisfactory to WEATHERFORD MUNICIPAL UTILITY
SYSTEM, up to and including the replacement of the non-qualified material.
5.2.6
The cellulose insulation barriers and spacers shall be high-density material (1.15 – 1.25
g/cc). Low-density pressboard is acceptable for formed insulation parts. The paper
insulation for winding conductors shall be high density, thermally upgraded, and shall
be Dennison 22HCC, Tullis-Russell Rotherm, or approved equal.
5.2.7
The winding conductor insulation shall be thermally stabilized. Insulation on all
conductors used in the coil winding process shall be cellulose insulating paper. It shall
be wound onto the conductor using a spinning process. The paper insulation shall be
applied in single or multiple strands such that a minimum of 30% of the paper surfaces
are overlapped to provide for a continuous insulating surface. Sufficient tension shall
be maintained on the paper strands so as to prevent loose wraps. Paper taped
conductor shall be supplied by Algonquin or approved equal. The performance of the
paper shall meet the following criteria:
5.2.8
The paper shall retain at least 50% of its original tensile strength after exposed to
110ºC for 50000 hours.
5.2.9
The paper shall have a degree of polymerization of at least 200 after 150000 hours at
110ºC.
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5.3
5.2.10
The electrical steel for the core shall be state-of-the-art material, H1 laser scribed
electrical steel supplied by AK Steel or approved equal.
5.2.11
Insulation for winding-to-bushing conductors and the leads to the DETC and LTC shall
be thermally upgraded material.
5.2.12
All material shall be traceable to its point of origin.
5.2.13
All material shall have test reports to verify that the material conforms to the applicable
standards. These reports shall be provided to WEATHERFORD MUNICIPAL
UTILITY SYSTEM upon request.
Bushings
5.3.1
The XV bushings shall be ABB cat. # 015W2000A or to WEATHERFORD
MUNICIPAL UTILITY SYSTEM engineer approved equivalent.
5.3.2
The X0 bushing shall be ABB cat. # 015W2000A or to WEATHERFORD
MUNICIPAL UTILITY SYSTEM engineer approved equivalent.
5.3.3
The HV bushings shall be ABB cat. # 138W0800AE or WEATHERFORD
MUNICIPAL UTILITY SYSTEM engineer approved equivalent.
5.3.4
Bushings that are bottom connected, shall have a non-plated brass connector, and be
designed for that application.
5.3.5
Request for variance approval shall be submitted to WEATHERFORD MUNICIPAL
UTILITY SYSTEM Engineer at least three weeks prior to the start of design review.
5.3.6
Bushing color shall be ANSI #70 light gray.
5.3.7
The BIL ratings for the bushings shall be as follows:
Terminals
HV
XV
5.4
BIL
650kV
110kV
Voltage Class
138kV
15kV
5.3.8
The HV bushings shall be located in segment 3, the XV bushings shall be located in
segment 1, and the X0 bushing shall line up with the other XV bushings adjacent to X1
bushing, per ANSI.
5.3.9
All bushings shall be supplied with stud to four-hole NEMA 4” X 4” pad connectors.
The four-hole NEMA pad shall have machined milled surfaces on both sides to permit
conductors to be attached to both sides. The connectors shall be suitable for
connection to aluminum bus or jumpers and copper bus.
5.3.10
Minimum center to center spacing of the 138kV bushings shall be 84 inches.
5.3.11
Minimum center to center spacing of the 13.09kV bushings shall be 30 inches.
Nameplate Requirements
5.4.1
The manufacturer shall supply all nameplates as specified in the ANSI/IEEE standards.
All nameplates shall be made from non-rust stainless steel or aluminum with Mil Spec
protective coating. The information contained on the nameplates shall be inscribed and
painted black. All the information shall be in English and in standard non-metric units
of measure.
5.4.2
The manufacturer shall indicate the total weight of cellulose insulation contained in the
transformer on the main nameplate.
5.4.3
A nameplate for series transformer and/or reactor shall be supplied on the main tank
nameplate when applicable.
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5.5
Current Transformers
5.5.1
Bushing current transformers for WEATHERFORD MUNICIPAL UTILITY
SYSTEM use shall be provided. The manufacturer shall install bushing-type current
transformers as indicated below.
5.5.2
Multi-ratio bushing current transformers shall conform to ANSI/IEEE. All current
transformers shall be ANSI Class C400, with a minimum Thermal Rating Factor (RF)
of 2.0, except for those CT’s needed solely for hot-spot calculations or for LDC inputs
which do not need to be C400. The following CT's shall be supplied, per phase:
Terminal
Number of CT's per phase
CT ratio
HV (H1, H2, H3)
2
400/5 multi-ratio with ANSI Standard taps
XV (X1, X2, X3)
2
2000/5 multi-ratio with ANSI Standard taps
XV (X0)
1
2000/5 multi-ratio with ANSI Standard taps
5.6
5.7
5.5.3
All secondary leads of current transformers shall be brought to a common outlet
housing near the cover and then to the weatherproof control cabinet. CT lead splicing
is not allowed. At the control cabinet each lead shall be terminated on a terminal block
with short circuiting provisions. Each multi-ratio current transformer shall terminate
on a separate block.
5.5.4
At least two (2) circular manholes shall be provided in the cover of the main tank to
allow the removal or addition of current transformers. Each manhole shall be a
minimum of 24” in diameter.
Surge Arresters
5.6.1
The transformer shall be provided with metal oxide station class surge arresters. The
HV arresters shall be ABB Cat # P120SA098A equipped with appropriate accessories.
The XV arresters shall be ABB Cat # P010SA008A.
5.6.2
The manufacturer shall provide mounting for the arresters. The manufacturer shall
minimize the distance between the surge arrester and the bushing. On the HV side, the
arrestor’s 4-hole pad shall be at the same elevation as the bushing’s 4-hole pad.
5.6.3
Surge Arresters shall be grounded to a minimum 4/0 AWG stranded bare copper ring.
The surge arrester grounding ring shall be bonded to ground pads at diagonal corners
of the transformer. Surge arrester ring shall be arranged so that it does not present a
tripping or falling hazard to personnel working on top of the transformer tank.
5.6.4
All surge arresters shall be manufactured and tested in accordance with ANSI/IEEE.
5.6.5
Each surge arrester shall be in line with its respective bushing.
De-energized Tap Changer
5.7.1
The transformer shall be provided with full capacity high voltage de-energized taps of:
131,100V; 134,550V; 138,000V; 141,450V; 144,900V (HV)
5.7.2
Operation of the de-energized tap changer from ground level is required. The deenergized tap changer position indicator shall be visible from ground level.
5.7.3
Provisions for padlocking shall be furnished for each de-energized tap position.
5.7.4
The de-energized tap changer shall be arranged to provide for inspection and
maintenance without un-tanking.
5.7.5
The de-energized tap changer shall be designed, manufactured, and tested to require
maintenance and moving of the tap changer to wipe the contacts at an interval of no
less than five years. Maintenance intervals of less than five years are not acceptable.
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5.7.6
5.8
The DETC shall be provided with silver plated contacts. There shall also be only one
external operating mechanism for a three phase DETC.
On Load Tap Changer (LTC)
5.8.1
The transformer shall be equipped with an automatic on load tap changer meeting the
following requirements:
5.8.2
The LTC equipment shall be a Reinhausen Type RMV-II tap changer.
5.8.3
The LTC and all associated windings shall be capable of operating at the maximum
transformer rating (MVA) continuously.
5.8.4
The manufacturer shall provide a separate complete nameplate for the LTC.
5.8.5
The regulating winding shall be fully distributed.
5.8.6
The LTC shall be located in the low voltage winding.
5.8.7
Provisions shall be provided for 32 steps. All tap positions shall be full capacity. Each
step will correspond to a change in voltage of 5/8 percent of center tap voltage
(13.09kV).
5.8.8
The transformer and the on load tap changer shall be designed to operate in a stepdown mode. The primary mode of operation of the LTC will be to keep the secondary
voltage constant as the load varies on the 12.47 kV system and as the voltage changes
on the 138 kV system.
5.8.9
The load tap changer control cabinet shall be located so it can be accessible from
ground level.
5.8.10
A table of voltages and currents for each LTC position at the 65° C maximum
nameplate rating at all tap voltages shall be provided on the nameplate.
5.8.11
Provisions for manual switching of the on load tap changer shall be made in the control
cabinet as follows:
5.8.12
Local/Remote Switch – A Local/Remote Control Switch shall be provided that can
switch control of the LTC from the control cabinet (local) to WEATHERFORD
MUNICIPAL UTILITY SYSTEM’ remote supervisory equipment (remote).
5.8.13
Auto/Manual Switch – An Auto/Manual Control Switch shall be provided that when
the Local/Remote Switch is in Local can switch the LTC from Manual to Automatic
mode.
5.8.14
Lower/Off/Raise Switch – A Lower/Off/Raise Control Switch shall be provided that
when the Local/Remote Switch is in Local and the Auto/Manual Switch is in Manual
can raise and lower the LTC. This is in addition to the maintenance switch required
under 5.8.46.
5.8.15
One spare contact for each position shall be provided for the Local/Remote Switch and
Auto/Manual Switch. These contacts shall be wired to a terminal block.
5.8.16
While the Local/Remote Switch is in the remote position, provisions shall be made for
the switching the on load tap changer control from auto to manual and from manual to
auto upon operation of a Form “C latching contacts from WEATHERFORD
MUNICIPAL UTILITY SYSTEM’ remote supervisory equipment.
5.8.17
While the Local/Remote Switch is in the remote position, the transformer tap position
may be changed upon receipt of a signal from WEATHERFORD MUNICIPAL
UTILITY SYSTEM remote supervisory equipment. The manufacturer shall provide
all the equipment in the transformer necessary to effect these operations. Every such
signal shall result in one tap position change, regardless of signal duration.
5.8.18
Provisions shall be provided for status indication to WEATHERFORD MUNICIPAL
UTILITY SYSTEM remote supervisory equipment when the LTC is in the automatic
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mode. This status should occur regardless of the position of the Local/Remote Switch.
This circuit can use an Auto control contact (closes when LTC is in automatic) from
WEATHERFORD MUNICIPAL UTILITY SYSTEM remote supervisory equipment.
WEATHERFORD MUNICIPAL UTILITY SYSTEM will provide a schematic
diagram for this circuit.
5.8.19
The on load tap changer motor shall be mounted in the control cabinet and it shall be
readily accessible with the transformer energized. The motor shall be equipped with
overcurrent protection with a manual reset.
5.8.20
The manufacturer shall wire all equipment control wiring to a terminal strip in the
control cabinet. WEATHERFORD MUNICIPAL UTILITY SYSTEM will connect
wiring for “Raise”, “Lower”, “Auto”, and “Manual” to this terminal strip.
5.8.21
The manufacturer shall provide one (1) mechanical counter to count all LTC
operations. The counter shall be easily readable from ground level.
5.8.22
The following electrical accessories shall be provided in the LTC control cabinet: one
(1) Waukesha positive coefficient heater to prevent condensation (no equivalent
accepted); one (1) 120 V, 100 W equivalent, mechanically protected fluorescent
outdoor light equipped with an outdoor fixture and outdoor door-operated switch; and
one (1) 120 V, 20 Amp, outlet equipped with a Ground Fault Interrupting Device
(GFCI). Each accessory shall be supplied from a separately protected circuit.
5.8.23
A mechanical position indicator with maximum and minimum indicating hands shall
be provided. The position indicator shall be visible through a window in the door of the
LTC control cabinet and shall also be visible from the manual control panel. The
manufacturer shall provide a push button to reset the maximum and minimum
indicating hands. The push button shall be located in the main control cabinet.
5.8.24
The manufacturer shall supply one (1) static voltage regulating relay, SEL catalog
number 243110111X114AXXXXXXX, to automatically control the operation of the
LTC. Potential input and relay output test switches shall be provided, such that the
customer can isolate the output contacts and test the device.
5.8.25
A neutral indicating contact shall be provided in the LTC mechanism, and wired to the
voltage regulating relay to assist the control in keeping track of LTC position.
5.8.26
The LTC type and rating shall be selected for a minimum of 500,000 operations at full
load before LTC contact maintenance is required. The LTC shall be designed to
achieve the full 500,000 operations on any combination of adjacent taps.
5.8.27
The manufacturer shall provide verification with the PROPOSAL submittal that the
selected LTC meets the requirements contained in this section. The verification shall
include, but not be limited to, the minimum number of operations before the
mechanism and contacts require maintenance and the calculations used to arrive at this
number.
5.8.28
The manufacturer shall provide one (1) combination 1” drain and sampling valve
located at the bottom of the LTC compartment. The sampling device shall be suitable
for use with ¼” I.D. Tygon tube for taking oil samples.
5.8.29
The manufacturer shall provide electrically interlocked hand crank for manual
operation of the LTC.
5.8.30
The manufacturer shall provide limit switches and mechanical stops to prevent overtravel of the drive mechanism, and the LTC motor drive mechanism shall not be
capable of being stopped in any off tap position due to loss of control power, motor
failure, or control problem.
5.8.31
The manufacturer shall provide one (1) rapid pressure rise sensing unit mounted on the
LTC compartment. The unit shall be equipped with test plugs to simulate a rapid
pressure rise so that the unit can be tested periodically. The rapid pressure rise sensing
unit shall be a Qualitrol Series 910 Rapid Pressure Rise Relay, or other manufacturer
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recommended relay with WEATHERFORD MUNICIPAL UTILITY SYSTEM
Engineer approval. The rapid pressure rise relay shall have a form “c” contact, which
will be used for tripping.
5.8.32
The manufacturer shall provide one (1) automatic pressure relief device, which can be
reset manually, mounted on each LTC compartment. The alarm contactor for this
device shall be routed to the main control cabinet. The automatic pressure relief device
shall be a Qualitrol Series 208 Pressure Relief Device.
5.8.33
The manufacturer shall provide one (1) magnetic liquid level gauge for the LTC. The
gauge shall include one form “c” contact for “LTC tank, low liquid level alarm” and
another form “c” contact for “LTC tank, low liquid level trip”, to operate when a risk
of a flash over can occur. These alarm and trip settings shall be set by the
manufacturer. The liquid level gauge shall have a six inch diameter dial. The magnetic
liquid level gauges shall be Qualitrol, or approved alternative, as agreed upon by
WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer. The gauge shall be
marked as to its intent.
5.8.34
The manufacturer shall provide terminal board points for PT terminations in the LTC
cabinet.
5.8.35
The manufacturer shall provide a ventilated weatherproof control cabinet with hinged
doors equipped with wind latches. The doors shall provide access to the control
devices and have provisions for padlocking. All cabinet and door hardware shall be
non-rust stainless steel.
5.8.36
A line-drop compensator (LDC) current transformer shall be provided on the X1
bushing. This CT shall have an output of 5 amps. A 5 amp to 0.2 amp transformer
(Beckwith M-0169A or approved equal) shall be used to convert the current to 0.2
amps for the voltage regulating relay.
5.8.37
If a series transformer or preventative autotransformer is used in the LTC circuit, the
windings of these transformers shall be the same type as the main windings. The
manufacturer shall use the same winding construction methods on all windings in the
transformer including the series transformer.
5.8.38
All exposed rotating drive shafts and related components shall be protected from
accidental contact with steel covers. The steel covers shall be of sufficient rigidity and
supported to prevent deformation.
5.8.39
Jacks for connecting a meter to monitor sensing potential shall be provided near the
voltage regulating relay.
5.8.40
LTC operation test switch and service light shall be provided near the voltage
regulating relay.
5.8.41
LTC off step alarm normally open contact shall be provided. This contact should not
close during normal operation of the LTC or for loss of AC.
5.8.42
All auxiliary transformers (preventive auto and series) shall be constructed to class 2
power transformer standards including circular core and coil design using all copper
conductors.
5.8.43
LTC sensing voltage shall be 120V, 60 Hz AC.
5.8.44
The LTC breather desiccant system shall be a Waukesha maintenance-free system, and
it must be accessible from ground level, no higher than four feet from the bottom of the
transformer tank.
5.8.45
Lead connections to the LTC terminal board shall be fastened with two bolts per
connection. All bolted electrical connections in the transformer are to be made with a
minimum of two bolts. The bolt pattern shall be a NEMA 2-hole pattern.
5.8.46
A raise, off, lower spring return selector switch shall be mounted in the LTC motor
housing near the on step position indicator. This switch shall bypass the LTC controls
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when the LTC Auto/Manual switch is in the Manual position. This switch will be used
when performing maintenance on the LTC.
5.9
Indicating Devices
5.9.1
Dial type indication gauges shall be non-removable, with tempered glass faces, and
shall be water resistant. All gauges shall be readable from the ground. That is, the
gauges shall be readable by a six foot tall person standing four feet from the base of the
transformer. The manufacturer shall tilt the gauges to allow this, if necessary, and if
allowable per manufacturer's instruction literature. All gauges equipped with drag
hands shall by located no higher than six feet above the transformer bottom, or shall be
equipped with remote reset buttons in the main control cabinet. Each terminal of every
switch shall be wired separately to a terminal strip in the main control cabinet. Leads
provided shall be long enough for a drip loop.
5.9.2
The manufacturer shall provide one (1) magnetic liquid level gauge for the main tank.
The gauge shall include one form “c” contact for “main tank, low liquid level alarm”
and another form “c” contact for “main tank, low liquid level trip”, to operate when a
risk of a flash over can occur. These alarm and trip settings shall be set by the
manufacturer. The liquid level gauge shall have a six inch diameter dial. The magnetic
liquid level gauges shall be Qualitrol, or approved alternative, as agreed upon by
WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer. The gauge shall be
marked as to its intent.
5.9.3
The transformer shall be equipped with a top oil temperature gauge, and a winding
temperature gauge. Both instruments shall be Qualitrol series 104, or
WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer approved equal. The
top oil temperature gauge shall have no less than two (2) user adjustable contacts. The
winding temperature gauge shall have no less than four (4) user adjustable contacts, of
which the first two will be used to control the fan stages. All necessary equipment to
simulate hot spot temperature shall be provided and calibrated.
5.9.4
The transformer main tank shall be equipped with a rapid pressure rise relay mounted
to sense pressure waves in the insulating oil. The relay shall be equipped with test
plugs to simulate a rapid pressure rise so that the unit can be tested periodically, and
shall be equipped with an isolation valve. The rapid pressure rise sensing unit shall be
a Qualitrol Series 900 Rapid Pressure Rise Relay, and shall have form “c” contacts,
which will be used for tripping.
5.9.5
One (1) cover mounted automatic pressure relief device, which can be reset manually
for each 10,000 gallons of oil shall be provided. The alarm contact shall be routed to
the main control cabinet. The pressure relief device shall be located such as to provide
optimal coverage on the cover. The automatic pressure relief device shall be a
Qualitrol or WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer approved
equivalent.
5.9.6
The manufacturer shall provide two (2) 3” combination upper filter valve on top of the
transformer. These valves shall be located on opposite ends on the short sides of the
transformer. The valves shall have deflectors and be arranged so it is suitable for the
return of filtered oil. An addition, install 1” threaded NPT on each manhole cover on
top of the transformer. The NPT in each manhole cover shall be located in such a
position and have appropriate deflectors to allow hot oil to splash onto the core.
5.9.7
The manufacturer shall also provide two (2) 2” combination drain and sampling valves
at the bottom of the transformer. These valves shall be located on opposite ends on the
short sides of the transformer.
5.9.8
All four combination filter/drain and sampling valves shall be of the globe type brass
valves and shall be located where there are no obstructions within 24” of the valve
vicinity. The valves shall have 2” NPT with a threaded pipe plug on the open end and
a flange on the other end. The flange connection to the main tank shall be welded. The
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bottom valves shall have a built-in sampling device, which shall be located in the
bottom of the valve between the main valve seat and the pipe plug. The sampling
device shall be supplied with 5/16”, 32 threads per inch, male connector equipped with
a gasketed screw-on cap. The sampling device shall be suitable for use with ¼” I.D.
Tygon tube for taking oil samples. All valves located within eight feet of ground level
shall be equipped with provisions for padlocking.
5.9.9
As a minimum, the following alarms shall be provided:
5.9.10
Winding Hot Spot Temperature, Major
5.9.11
Winding Hot Spot Temperature, Minor
5.9.12
Top Oil Temperature, Major
5.9.13
Top Oil Temperature, Minor
5.9.14
Pressure relief device operation - Main Tank
5.9.15
Pressure relief device operation – LTC
5.9.16
Low oil level - Main tank
5.9.17
Low oil level – LTC
5.9.18
LTC - upper limit over travel
5.9.19
LTC - lower limit over travel
5.9.20
LTC off step
5.9.21
LTC voltage regulator failure alarm
5.9.22
LTC backup regulator failure alarm
5.9.23
LTC Vacuum bottle failure alarm
5.9.24
AC failure alarms
5.9.25
Low nitrogen pressure alarm
5.9.26
High nitrogen pressure alarm
5.9.27
Empty nitrogen cylinder alarm
5.9.28
All indicating and tripping devices mentioned shall have their alarm and trip contacts
wired to a terminal strip in the control cabinet. Connection of the indicating devices to
the annunciator shall be from this terminal strip. Separate points for each sudden
pressure relay alarm on the annunciators shall be provided. All alarm and relay
contacts shall be rated for use at 250 VDC.
5.9.29
The manufacturer shall provide, installed on the swing out control cabinet inner door,
wire to the terminal strip mentioned in section 5.10.28: a SEL 2523013100XA0XX
annunciator panel. All the alarms noted in 5.9.9 shall be wired to separate points on the
annunciator.
5.10 Cooling Equipment
5.10.1
Removable, unpainted galvanized radiators with top and bottom shutoff valves shall be
provided. Each radiator segment and any removable headers shall be equipped with
lifting eyes, and a suitable drain valve.
5.10.2
The control of the oil cooling devices shall be actuated by winding temperatures and
shall progress in accordance with the provisions for two stage cooling as described in
ANSI/IEEE.
5.10.3
In addition to normally provided controls, each set of cooling equipment shall be
provided with an automatic/manual selector switch to permit operation of all cooling
equipment simultaneously for test purposes.
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5.10.4
All fan motors shall be connected for 240VAC, single phase, 60 Hz. Individual
motors shall be single phase and be equipped with sealed ball bearings and an
individual thermal protective device equipped with automatic reset. Fan motors shall
be arranged with suitable wiring connectors such that if defective they may be removed
for maintenance without taking the transformer out of service. Fan motors shall be UL
or CSA recognized, and to match existing WEATHERFORD MUNICIPAL UTILITY
SYSTEM stock, shall be Krenz-Vent Model F26-A8678 fans equipped with KrenzVent CON-A8318/A8317 cord sets. All fans shall be provided with blade guards that
meet OSHA requirements. Fan motors shall be rated for 230V AC.
5.10.5
The fans are to be mounted on the radiators in such a way as to enhance maintenance in
service. The spacing between adjacent radiator banks with fans mounted on them shall
be of sufficient dimension so fans may be replaced without having to remove radiators
to remove fans. Fan mounting hardware shall be independently clamped or mounted
so that removal of fans does not allow mounting hardware to fall loose.
5.11 Oil Preservation System
5.11.1
The oil preservation system shall be an inert gas pressure system or WEATHERFORD
MUNICIPAL UTILITY SYSTEM engineer approved equivalent. System shall be
complete with low and high pressure, as well as empty cylinder alarms, and all
associated controls. All of these items shall be mounted in a weatherproof
compartment mounted on the transformer. The bottom of the nitrogen bottle shall be
mounted no higher than six inches above foundation level. Alarm contacts shall be
provided with leads wired to terminal strips in the control cabinet. All door hardware
and mounting hardware shall be non-rust stainless steel. The door shall be equipped
with a window to allow reading the bottle and transformer tank pressure gauges
without opening the door.
5.11.2
A main tank sample point shall be provided for dew point measurements that take the
sample from the main tank directly and not through the bracing or other parts of the
tank that would not be a representative sample of what is inside the main tank. This
sample point shall be reachable from the ground without a ladder or other climbing aid.
5.12 Control Cabinets
5.12.1
All current transformer (CT) circuits, alarm circuits, potential circuits, and other
circuits shall be housed in a single weatherproof cabinet.
5.12.2
All taps of all current transformer circuits shall be wired to terminal strips equipped
with shorting bars (Marathon 1500 Series or WEATHERFORD MUNICIPAL
UTILITY SYSTEM engineer approved equivalent). All CT wiring shall be No. 10
AWG copper wire, 600 Volt insulation, NEC MTW rated.
5.12.3
The control cabinet shall be accessible from ground level. The bottom of the cabinet
shall be a minimum of 18 inches above the base. All cabinet and door hardware shall
be non-rust stainless steel.
5.12.4
The control cabinet shall accommodate an uncut, removable, aluminum bottom plate to
accommodate conduit entry. The removable plate shall be no less than 12” x 24” in
size. A clear path shall be provided between the conduit entrance and all terminal
boards.
5.12.5
The following electrical accessories shall be provided in the main control cabinet: one
(1) Waukesha positive coefficient heater to prevent condensation (no alternate
accepted); one (1) 120 V, 100 W equivalent, mechanically protected incandescent
outdoor light equipped with an outdoor fixture and outdoor door-operated switch; and
one (1) 120 V, 20 Amp, dual receptacle outlet equipped with a Ground Fault
Interrupting Device (GFCI). The receptacle outlet shall be accessible from the outside
of the control cabinet without having to open any control cabinet doors. Each
accessory shall be supplied from a separately protected circuit.
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5.12.6
All transformer auxiliary wiring shall be a minimum of No. 14 AWG copper wire,
600V insulation, NEC MTW rated. The auxiliary wiring shall be captively identified
at both ends and routed to the control cabinet in galvanized conduit and fittings. All
wiring shall be stranded conductors. Analog or digital signal paths may be wired with
No. 18 AWG wire.
5.12.7
All wiring shall be flame resistant, oil resistant, heat resistant, and moisture resistant.
All wiring shall be complete and performed in a professional manner and bundled or
contained. No device relying on adhesive may be used to secure wiring.
5.12.8
Splices in wiring will not be allowed.
5.12.9
Each end of all conductors shall be permanently tagged and identified. The tag shall list
the destination device designation and terminal number where the wire is landed. The
method of permanently tagging the conductor ends shall be approved by
WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer. Wire ends shall be
permanently fitted with compression type, ring lugs before attaching securely to
terminal studs. Open spade or fork connectors will not be accepted. Pins or ferrules
shall be used on cage type terminals. Bare stranded wires shall not be used for any
terminations.
5.12.10 No more than two wires shall be connected on one terminal.
5.12.11 The manufacturer shall design the layout of the electrical wiring in the control cabinet
to segregate the manufacturer’s wiring from WEATHERFORD MUNICIPAL
UTILITY SYSTEM wiring. Terminal boards shall be wired with one side reserved for
the manufacturer and one side reserved for WEATHERFORD MUNICIPAL UTILITY
SYSTEM. Factory wiring shall not be terminated on the side of the terminal boards
reserved for WEATHERFORD MUNICIPAL UTILITY SYSTEM use. Some method
should be provided to guide and anchor WEATHERFORD MUNICIPAL UTILITY
SYSTEM field wiring.
5.12.12 Terminal boards for control wiring shall be solid molded blocks, rated 600 Volts and a
minimum of 30 Amperes per terminal and able to accommodate wire sizes up to and
including #10 AWG. No less than 20% of the terminal block positions shall be unused,
to be reserved for future applications.
5.12.13 All screw-type terminal blocks shall be outfitted with slotted head screws. Phillips
head screws will not be allowed.
5.12.14 All control wiring shall be wired to #10-32 barrier type terminal strips properly sized to
handle the loads (Marathon 1500 Series or WEATHERFORD MUNICIPAL UTILITY
SYSTEM engineer approved equivalent). Terminal board covers are not desired.
However, a white marking strip shall be furnished, marked, and attached so that
terminal points can be identified. Terminal board points for terminating transformer
AC supply for fans, pumps, LTC drive, etc. shall accept the appropriate size of cable
for the required ampacity and voltage drop. The use of “plug-in” terminal boards will
not be allowed. Internal jumpers shall be provided so that AC power and DC power
may be landed at only one point.
5.12.15 All devices in control cabinet shall be permanently identified and marked with
appropriate reference designator as shown on the manufacturer supplied schematic and
wiring diagrams.
5.12.16 All control cabinet doors shall be supplied with wind latches. If multiple doors are
used in the control cabinet, the wind latches of the inner door shall attach to the outer
door.
5.12.17 The control cabinet shall be equipped with a weatherproof pocket mounted on the
inside of the control cabinet door. The weatherproof pocket shall be of sufficient size
to accommodate the instruction book and all drawings. The weather pocket shall have
a hinged top cover to facilitate retrieval of the instruction book and drawings. The
weatherproof pocket shall not interfere with the operation of the relays inside the
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control cabinet with the door closed. Sufficient clearance shall be maintained between
the weatherproof pocket and the devices inside the control cabinet with the doors in the
closed position.
5.12.18 The control cabinet shall be equipped with a drip shield to prevent rainwater from
dripping into the control cabinet with the doors in the open position.
5.13 Auxiliary and Control Power
5.13.1
WEATHERFORD MUNICIPAL UTILITY SYSTEM will provide the 120/240, single
phase 3 wire power sources necessary to operate the on load tap changer, cooling
equipment, and control circuits.
5.13.2
120/240V AC loads shall be supplied by molded-case circuit breakers properly sized
for the loads. Molded-case circuit breakers shall be rated at 240V AC. Molded case
circuit breakers are to be used exclusively. Knife switches and fuses are not allowed.
The manufacturer shall provide a main 120/240V AC power panel. Each power panel
shall be properly identified. All circuit breakers shall have an interrupting rating of 10
kA.
5.13.3
All AC circuits shall be wired using appropriate wire sizes.
5.13.4
AC failure relays with form “c” alarm contacts shall be provided for the 120/240V AC
circuits. A single phase AC failure relay and alarm shall be provided for single phase
120V circuits. The alarms shall have an adjustable time delay of up to five minutes.
The contacts shall be wired to terminal blocks for WEATHERFORD MUNICIPAL
UTILITY SYSTEM use and to the annunciator. An AC failure relay shall be installed
at the end of the following AC circuit strings:
5.13.5
Stage 1 Cooling
5.13.6
Stage 2 Cooling
5.13.7
Cooling Controls
5.13.8
LTC Controls
5.13.9
LTC Motor
5.13.10 Each of the following circuits shall have overcurrent protection using a molded-case
circuit breaker:
5.13.11 Stage 1 Cooling
5.13.12 Stage 2 Cooling
5.13.13 Cooling Controls
5.13.14 LTC Controls
5.13.15 LTC Motor
5.13.16 Heaters
5.13.17 LTC filter if needed
5.13.18 Lights and receptacles
5.14 Grounding
5.14.1
The manufacturer shall install external core ground test points from each individual
core section to an external core ground bushing located on the top or side of the
transformer. This shall include the core for the main transformer windings, core for the
preventative autotransformer, and core for the series transformer. These bushings shall
be capable of withstanding 1500 volts D.C. The core ground bushings shall be
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protected with a weatherproof enclosure. Removable ground links shall be provided to
ground the core ground bushing to an adjacent ground point within the enclosure.
5.14.2
A minimum of four (4) two-hole NEMA copper faced steel ground pads shall be
provided. Each pad shall have two holes horizontally spaced on 1 ¾ inch centers and
drilled and tapped for ½ - 13 UNC thread to minimum depth of ½ inch. The pads shall
be welded to the base of the main tank on all four corners.
5.14.3
The XO bushing shall be connected to the ground pad on the bottom of the low voltage
side of the transformer using copper bus bar that has a rating equal to maximum phase
current. The bus shall be insulated from the transformer tank using standoff insulators.
A flexible strap between the end of the bus bar and bushing shall be provided. This
strap shall have a current rating that is equal to or greater than the bus bar and shall be
easily disconnected for testing purposes. The XO bushing shall not be grounded to the
transformer except through the bus bar and strap as described.
5.14.4
All grounding jumpers shall be bare copper, 2/0 AWG minimum. Insulated conductor
shall not be used in weather exposed area as grounding jumpers.
5.15 Handling
Lifting, moving, and jacking facilities shall be provided. The jacking/lifting lugs shall be suitable
for use with 17 inch high jacks. Lifting eyes shall be provided on all covers, as well as on the tank.
Pulling eyes shall be provided for the attachment of a pulling rig. This allows for movement of the
transformer along the direction of either centerline. Jacking lugs and lifting eyes shall be provided
with identifying tags.
5.16 Vacuum Filling
The transformer tank, LTC compartments, LTC conductor pass-through boards, and radiators shall
be capable of withstanding full vacuum.
5.17 Paint Requirements
5.17.1
The transformer and control cabinets shall be painted inside and outside. Interior of
tank and tank cover shall be painted white. The interior of the control cabinets shall be
painted white.
5.17.2
The finish coat shall be ANSI 70 Grey, except as noted in Section 5.16.3.
5.17.3
The interior of the transformer tank, the core frames, and the interior of the control
cabinets shall be finished with a Federal Std. No. 595-B White No. 7875 paint or
equivalent color.
5.17.4
The total finish on non-weather exposed surfaces shall be at least three mils in
thickness.
5.17.5
The manufacturer shall provide a skid resistant and flame retardant finish on the top of
the transformer.
5.17.6
All primer and paint shall be lead free.
5.17.7
The manufacturer shall provide a separate non-prorated warranty on the finish for a
five year period. The warranty shall cover rust, rust bleed-through, flakes, paint fading,
and paint chipping.
5.17.8
Paint shall be uniform and even, free of runs, sags, checks, or blisters. Any defects
appearing during the warranty period shall be repaired by and at the expense of the
manufacturer.
5.17.9
A protective undercoat shall be applied to the base and the bottom surface of the
transformer tank.
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5.18 Insulating Oil
5.18.1
The manufacturer shall be responsible for vacuum processing and filling the
transformer. The manufacturer shall furnish sufficient transformer insulating oil in
clean tank trucks with sealed pumps and hoses at the job site. The manufacturers
personnel shall be available at the job site to receive the delivery. The tank trucks shall
be certified clean and dry.
5.18.2
The oil shall conform to the latest revision of ANSI/ASTM D3487-1988, Type II. The
gassing coefficient shall be negative when tested in accordance with ASTM D23001998. Oil with a negative gassing coefficient is preferred but a slightly positive gassing
coefficient is acceptable with approve of WEATHERFORD MUNICIPAL UTILITY
SYSTEM Project Engineer.
5.18.3
The oil shall be free of corrosive sulfur as tested by the Doble enhanced method.
5.18.4
The manufacturer shall supply the following information for the oil used in the
transformer during dielectric testing:
5.18.5
Power factor at 25° C and 100° C
5.18.6
Water content in PPM
5.18.7
Dielectric when tested in accordance with ASTM D1816-1997 using a 40 mil gap
5.18.8
Interfacial tension
5.18.9
Color
5.18.10 Gassing coefficient, ASTM D2300-1998
5.18.11 Neutralization number
5.18.12 Inhibitor
5.18.13 PCB content
5.18.14 The manufacturer shall specify their minimum characteristics for the oil to be used in
their factory and at the installation site. The characteristics of the oil at the site shall
not be less than that required at the factory for testing.
5.18.15 The transformer nameplate shall note that the oil in the transformer when filled at the
site is “PCB FREE.”
6.0
INSPECTION and TEST REQUIREMENTS
6.1
Observation Rights
6.1.1
WEATHERFORD MUNICIPAL UTILITY SYSTEM reserves the right to visit the
manufacturing facility and to observe the transformer while undergoing construction
and testing. The manufacturer may not charge WEATHERFORD MUNICIPAL
UTILITY SYSTEM for its right to visit the facility during construction and testing.
WEATHERFORD MUNICIPAL UTILITY SYSTEM shall be notified at least three
weeks (3) prior to the implementation of the required tests. If three (3) weeks notice is
not given before the start of testing, WEATHERFORD MUNICIPAL UTILITY
SYSTEM reserves the right to have the manufacturer delay the testing until the first
time in which WEATHERFORD MUNICIPAL UTILITY SYSTEM inspector(s)
assigned to this purchase are available. Furthermore, if WEATHERFORD
MUNICIPAL UTILITY SYSTEM inspector(s) arrives on site and the transformer is
not ready for testing within eight (8) hours, WEATHERFORD MUNICIPAL UTILITY
SYSTEM reserves the right to postpone the testing for up to three (3) weeks and the
manufacturer shall reimburse WEATHERFORD MUNICIPAL UTILITY SYSTEM
for any travel and labor cost incurred by WEATHERFORD MUNICIPAL UTILITY
SYSTEM due to manufacturer’s delays. This reimbursement shall not be limited to one
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inspector but all WEATHERFORD MUNICIPAL UTILITY SYSTEM representatives
who have traveled to the manufacturer’s facility. A third party transformer inspector
may be employed at WEATHERFORD MUNICIPAL UTILITY SYSTEM discretion,
and shall enjoy the same rights and privileges as a WEATHERFORD MUNICIPAL
UTILITY SYSTEM employee.
6.2
6.1.2
Delays caused by WEATHERFORD MUNICIPAL UTILITY SYSTEM exercising its
rights as per the above paragraph shall not relieve the manufacturer from meeting the
required delivery dates.
6.1.3
If the English language is not the primary language used at the factory then an
interpreter shall be provided whenever a WEATHERFORD MUNICIPAL UTILITY
SYSTEM representative is at the manufacturer’s location for factory inspection, design
review, core and coil inspection, and testing and for any other interaction as required.
This interpreter shall be available to the WEATHERFORD MUNICIPAL UTILITY
SYSTEM representative at all times when the representative is at the manufacturer’s
location. The interpreter shall also be available outside the factory if the
WEATHERFORD MUNICIPAL UTILITY SYSTEM REPRESENTATIVE requests
their presence. The manufacturer shall pay for all costs for the interpreter.
Routine Tests
All routine tests listed in Section 8.2.1 of ANSI/IEEE C57.12.00-2000 shall be performed on the
transformer in accordance with ANSI/IEEE C57.12.90-1999.
6.3
Additional Tests
If a problem occurs during any dielectric test, which results in the lowering of the oil and repairs
below the top of the core and coil assembly, all dielectric tests completed up to that point shall be
repeated.
6.3.1
All testing shall be performed with the transformer fully assembled. The bushings to
be shipped with the transformer, oil preservation system, and heat exchangers shall be
installed on the transformer and shall be used during all the testing.
6.3.2
Insulation power factor tests shall be performed prior to any power frequency voltage
being applied to the transformer. The testing shall be in accordance with ANSI/IEEE
C57.12.90. The maximum acceptable power factor is 0.5% when corrected to 20° C.
6.3.3
Load Losses and Impedance
6.3.4
Measure the load losses and impedance’s (HV to LV) at the following LTC positions
on the self cooled ratings:
Neutral, 1R, 16R, and 16L.
6.3.5
The method for measuring the load losses must be specified in the PROPOSAL. Only
methods that have sufficient accuracy for measuring losses at low power factor are
acceptable. See Section 4.4.2.
6.3.6
No-Load Loss and Excitation Current Tests
Measure no-load losses and exciting current at 90%, 100%, 110% voltage before and after
the impulse tests. The values measured after the impulse tests will be used for guarantee
purposes. The no-load losses and exciting current shall be measured at LTC positions 16L,
neutral, 1R, 16R, and no-load loss guarantee position, if different from 1R.
If the transformer has a LTC that uses variable volts per turn design, the no-load losses and
exciting current shall be measured and guaranteed on the LTC position having the highest
no-load losses.
6.3.7
Lightning Impulse Tests
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6.3.8
All winding and neutral terminals shall be tested in accordance with ANSI/IEEE
impulse test standards for the BIL specified and in accordance with this specification
for both HV windings in series and in parallel.
6.3.9
The voltage and current traces for all impulse tests shall be recorded utilizing HIAS
computerized registration system or equivalent. The actual electronic files shall be
submitted on CD ROM when requested by WEATHERFORD MUNICIPAL UTILITY
SYSTEM engineer.
6.3.10
Discrepancies or differences on impulse test oscillograms will not be allowed except
those caused by integral protective devices as outlined in ANSI/IEEE C57.98-1993 and
ANSI/IEEE Std. 4-1995. If such discrepancies or differences exist due to circuitry or
other problems on any phase, the problem shall be corrected and all tests shall be
repeated on all phases already tested.
6.3.11
If there is a substantial time delay (30 minutes or greater) between the impulse tests on
any terminal, then the impulse test sequence shall be restarted on that terminal from the
beginning.
6.3.12
A series of full wave and chopped wave, impulse tests shall be conducted on terminals
H1, H2, H3, X1, X2, X3, and X0 in accordance with ANSI/IEEE C57.12.90-1999.
Strict adherence to the order of the impulse tests is required. The test sequence to be
used on H1, H2, H3, X1, X2, and X3 shall be as follows:
one (1) Reduced Full Wave
one (1) Full Wave
one (1) Reduced Wave
two (2) Chopped Waves
one (1) Full Wave
one (1) Reduced Full Wave
The test sequence to be used on X0 shall be as follows:
one (1) Reduced Full Wave
two (2) Full Waves
6.3.13
one (1) Reduced Full Wave
6.3.14
Applied Voltage Test
6.3.15
The applied voltage test shall be made in accordance with the appropriate ANSI/IEEE
standards and with the following test voltages:
HV
LV
208kV
26kV
6.3.16
Noise Test
6.3.17
Transformer sound measurements shall be made on each transformer in accordance
with ANSI/IEEE C57.12.90. The PROPOSAL should outline the cost of noise testing
and note if noise testing has been performed on duplicate units. WEATHERFORD
MUNICIPAL UTILITY SYSTEM reserves the option of waiving the noise testing and
deducting that cost.
6.3.18
Induced Voltage Tests with Partial Discharge Measurements
The low frequency induced voltage test with partial discharge measurements shall be made
in accordance with ANSI/IEEE standards as specified for Class II transformers with the
following modifications.
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6.3.19
Apparent partial discharge shall be measured and reported both in terms of the RIV at
1MHz, generated in accordance with ANSI C57.12.90, and in terms of Pico-coulombs
for wide band in accordance with ANSI/IEEE C57.113.
6.3.20
RIV shall not exceed 100 microvolts at 1.5 times the maximum system voltage
specified by ANSI C84.1. The measured partial discharge shall not exceed 500 PicoCoulombs.
6.3.21
The partial discharge shall be measured and recorded at the 150% level as the voltage
is being increased to the enhancement level of 173%.
6.3.22
The partial discharge shall be measured and recorded at the enhancement level.
6.3.23
The first reading at 150% following the enhancement shall be taken five minutes after
the voltage reaches the 150% level and every five minutes thereafter for one hour.
6.3.24
The partial discharge level shall not exceed 100 microvolts or 500 Pico-Coulombs
during the hour. The partial discharge level shall not increase more than 30 microvolts
or 150 Pico-Coulombs during the hour using the value at 150% prior to the
enhancement as the base reading. There shall be no continuous increase during the
hour or during the last 20 minutes of the hour.
6.3.25
In the event that the 100 microvolts limit or the 500 Pico-Coulombs limit, the 30
microvolts increase or the 150 Pico-Coulombs increase or the continuous increase
requirement are exceeded, the cause shall be determined and corrected.
In the event that a deviation from the specification exists, WEATHERFORD MUNICIPAL
UTILITY SYSTEM, in conjunction with the manufacturer, will consider available options
including extended testing. The final course of action must be acceptable to
WEATHERFORD MUNICIPAL UTILITY SYSTEM.
6.3.26
Other Tests
6.3.27
A turns ratio test shall be performed with the series-parallel switch in the series
position on all LTC tap positions with the DETC at position 3. A turns ratio test shall
be performed on all DETC tap positions with the LTC at position 0. Turns ratio test
results should not deviate more than one-half of one percent (0.5%) from the nameplate
ratio. The turns ratio tests shall be repeated with the series-parallel switch in the
parallel position.
6.3.28
Resistance tests shall be made on all taps. Winding temperature should be recorded at
the time of the test. Winding resistance test results from the different phases shall
compare within one percent (1%) of adjacent windings.
6.3.29
Current Transformer Tests
The current transformers shall be tested in accordance with ANSI/IEEE C57.13-1993. The
testing shall include, but not be limited to, the following:
6.3.30
Ratio and phase angle
6.3.31
Excitation
6.3.32
Polarity
6.3.33
Burden
6.3.34
Winding and lead resistance
6.3.35
Insulation resistance
6.3.36
Control and Power Wiring Tests
Low frequency withstand voltage tests shall be performed on all control and secondary
wiring in accordance with Section 5.17 of ANSI/IEEE C37.09-1999. All low voltage
wiring, including control and indication wiring, shall be given full functional tests. Tests
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shall be performed on the LTC controller to ensure proper operation. Quality control and
assurance tests results shall be made available to WEATHERFORD MUNICIPAL
UTILITY SYSTEM inspector upon request.
6.4
6.3.37
Special Test Requirements
6.3.38
All testing shall be accomplished using the United States 60 Hz standard. Testing
using 50 Hz and then calculating the results at 60 Hz will not be accepted.
6.3.39
All devices shall be connected and function during testing. This includes but is not
limited to the LTC controls, cooling controls and devices, winding temperature
instruments.
6.3.40
There shall be no intentional delays in the entire dielectric test sequence. The lightning
impulse tests, applied voltage tests, and induced voltage tests shall be carried out
continuously with minimal delays to allow only for the test circuit setup.
6.3.41
The entire test sequence shall be repeated if failure occurs at any time during the test
sequence that requires untanking, repairs, and or rework of the active parts.
6.3.42
If any repairs are performed during or after testing the manufacturer shall re-perform
any tests requested by any WEATHERFORD MUNICIPAL UTILITY SYSTEM
representative at no cost to WEATHERFORD MUNICIPAL UTILITY SYSTEM.
6.3.43
WEATHERFORD MUNICIPAL UTILITY SYSTEM shall be notified immediately of
any failure of testing and all testing shall be stopped at that time until course of action
is determined by WEATHERFORD MUNICIPAL UTILITY SYSTEM. The
manufacturer may be required to repeat testing already performed to satisfy reason of a
failed test at no cost to WEATHERFORD MUNICIPAL UTILITY SYSTEM.
6.3.44
The frequency response test shall be performed before shipment of the transformer.
WEATHERFORD MUNICIPAL UTILITY SYSTEM will determine if the test is
performed using the impulse method or the sweep frequency response technique.
6.3.45
A temperature test is required for the first unit of any order. The submittal of thermal
duplicate data will not be accepted. The temperature transformer is to include the
ONAN and ONAF2 tests. Oil samples shall be taken at the start of the test and at the
end of the test sequence and the change of gas quantities shall be limited as follows:
hydrogen – 10 ppm, methane – 5 ppm, ethane – 2 ppm, ethylene – 2 ppm, acetylene –
non detectable, carbon monoxide – 25 ppm, and carbon dioxide – 250 ppm.
Test Reports
6.4.1
Four (4) sets of the certified test reports shall be provided for each transformer. The
manufacturer shall also present evidence of quality control testing and proof that the
transformer has passed these tests. WEATHERFORD MUNICIPAL UTILITY
SYSTEM shall approve the transformer quality control test results before the shipment
of the transformer. All reports shall be in English and in standard non-metric units of
measure.
6.4.2
The test reports shall be printed on 8 ½” x 11” size paper and shall be bound in a
lightweight folder with the manufacturer and the serial number clearly printed on the
cover.
6.4.3
As a minimum, the test reports shall include the following:
6.4.4
Copy of all impulse traces with a complete sequential listing of all impulses, including
calibration shots and actual failure shots if any.
6.4.5
Schematic diagrams of the test circuit for all tests performed and the instruments used
in registering the test data.
6.4.6
Copy of the recorder chart for all temperature readings during temperature rise test and
loss data during no-load loss and load loss measurements.
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7.0
6.4.7
All work sheets and rough data shall be supplied to WEATHERFORD MUNICIPAL
UTILITY SYSTEM engineer.
6.4.8
Photographic record of the manufacturing of the transformer from digital images taken
by high-resolution, 4 megapixel, digital camera shall be submitted. Each print shall be
at least 4” x 7” in size. The prints shall be provided on high (archival) quality photo
paper printed by a high resolution color printer. The camera and associated equipment
used to take the photographs shall be approved by WEATHERFORD MUNICIPAL
UTILITY SYSTEM Engineer. All digital images shall be provided to the
WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer on a CD-ROM disk.
As a minimum, the following photographs shall be included:
6.4.9
Photos of each winding type.
6.4.10
Photos of the core steel before installation of the windings.
6.4.11
Photos of the assembled unit before tanking, including photos of the completed lead
structures, the LTC, and the DETC.
6.4.12
Photos of the assembled unit after tanking.
OTHER REQUIREMENTS
7.1
Drawings
7.1.1
The manufacturer shall furnish engineering drawings that are sufficient for design and
construction of the foundations for the transformer within ten weeks after receipt of the
order. All the information shall be in English and in standard non-metric units of
measure. The following information must be furnished:
7.1.2
Tank bottom dimensions within ± 4”.
7.1.3
Heights
7.1.4
Base to cover ±4”
7.1.5
Base to bushing terminals ± 5′′
7.1.6
Location of bushings from center lines of tank ± 4′′
7.1.7
Weights, ± 5%, with and without oil
7.1.8
Location of control cabinets within ± 3′′ from the tank centerline
7.1.9
Location and size of WEATHERFORD MUNICIPAL UTILITY SYSTEM conduit
entrance to the control cabinet
7.1.10
Power and voltage requirements of the cooling equipment
7.1.11
The number and size of wires that WEATHERFORD MUNICIPAL UTILITY
SYSTEM must supply for power supply, controls, alarms, and the monitoring system
in enough detail for the size of the incoming conduits to be determined
7.1.12
A schematic wiring diagram
7.1.13
Detailed engineering drawings shall be provided to WEATHERFORD MUNICIPAL
UTILITY SYSTEM’ Project Engineer for approval prior to the start of material
purchasing or construction.
7.1.14
The manufacturer shall furnish two (2) complete sets of drawings for approval. The
manufacturer shall also provide two (2) copies of the operation and maintenance
manuals for approval. Partial sets are not acceptable. Each approval drawing set shall
include, but not be limited to, the following:
7.1.15
Outline drawings of the transformer packaged for shipping and the outline drawings of
the fully assembled transformer for service
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7.1.16
Bushing outline drawings
7.1.17
Connection diagrams showing where external WEATHERFORD MUNICIPAL
UTILITY SYSTEM cable connections are provided
7.1.18
Control and alarm schematics
7.1.19
Wiring diagrams showing all internal control wiring including LTC. The wiring
diagrams shall show next to each terminal the destination by device name and terminal
number where the wire is landed. Wiring lists and drawing grid location with wire
names methods are not acceptable.
7.1.20
Nameplate drawings
7.1.21
Current transformer characteristic curves
7.1.22
Internal core and coil assembly drawings and lead arrangement drawings
7.1.23
Detailed 3D color drawings of the transformer internal layout and details. The intent of
this is to receive the parametric model drawings that are generated as part of the
transformer design using ProE or similar program.
7.1.24
WEATHERFORD MUNICIPAL UTILITY SYSTEM requires fifteen (15) working
days after the receipt of approval drawings and manuals to review and return the
approval drawings to the factory. The manufacturer shall not start actual construction
until all issues are resolved on the drawing approval process.
7.1.25
The manufacturer shall furnish one (1) set of “Certified For Construction” outline,
nameplate, electrical, control, and relay drawings prior to shipment of the transformer.
These drawings shall also be provided in AutoCAD .DWG format on CD ROM.
Translation programs and drawing attributes will not be allowed for schematics, wiring
diagrams, and any other drawings that WEATHERFORD MUNICIPAL UTILITY
SYSTEM may need to edit in the future. These drawings shall be submitted to
WEATHERFORD MUNICIPAL UTILITY SYSTEM within twenty weeks from the
date of the Purchase Order or prior to construction, whichever is earlier. The
manufacturer shall stamp “CERTIFIED FOR CONSTRUCTION” and the current date
on these drawings.
7.1.26
The drawing sets shall include, but not be limited to, the following:
7.1.27
Outline drawings of the transformer packaged for shipping and the outline drawings of
the fully assembled transformer for service
7.1.28
Bushing outline drawings
7.1.29
Connection diagrams showing where external WEATHERFORD MUNICIPAL
UTILITY SYSTEM cable connections are provided
7.1.30
Control and alarm schematics
7.1.31
Wiring diagrams showing all internal control wiring including LTC. The wiring
diagrams shall show next to each terminal the destination by device name and terminal
number where the wire is landed. Wiring lists and drawing grid location with wire
names methods are not acceptable.
7.1.32
Nameplate drawings
7.1.33
Current transformer characteristic curves
7.1.34
WEATHERFORD MUNICIPAL UTILITY SYSTEM will have final approval of the
format and content of the final drawings.
7.1.35
The manufacturer shall provide four (4), including one (1) shipped with the
transformer, complete sets of installation, operating, and maintenance instruction books
for each of the transformer components and each relay and control device. These
materials shall be printed on 8 ½” x 11” paper, and bounded in heavy duty three-ring
binders suitable for reference and filing with the particular model supplied clearly
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noted on documents that apply to more than one (1) type or model. Each set of the
instruction books shall include a spare parts list detailing the manufacturer, catalog
numbers, price, and ordering information. Each instruction book shall have a complete
set of “as-built drawings” including the internal core and coil assembly drawings and
lead arrangement drawings included in the binder on 11” x 17” sheets. The color 3D
parametric modeling drawings shall be included on 8 ½” x 11” sheets. The
manufacturer shall stamp “AS BUILT” and current date on these drawings. If
revisions to the “as built” drawings are necessary, the manufacturer shall pack the latest
copy of the “as built” drawings with the transformer and shall send the revised
drawings within two (2) weeks after shipment of the transformer. The instruction books
and spare parts lists shall be submitted to WEATHERFORD MUNICIPAL UTILITY
SYSTEM no later than one (1) month prior to the agreed delivery date of the
transformer.
7.1.36
The manufacturer shall provide one (1) complete set of “as built” drawings in
Microstation .DGN format or AutoCad .DWG format and the complete instruction
manual shall be included on CD ROM(s) and placed in the instruction manual pouch of
each instruction book. The text documents shall be in Microsoft Word format. The
Instruction Manuals shall be in Adobe pdf format. The 3D parametric modeling
drawings shall be converted to picture files using a .JPG format. Translation programs
and drawing attributes will not be allowed for schematics, wiring diagrams, and any
other drawings that WEATHERFORD MUNICIPAL UTILITY SYSTEM may need to
edit in the future.
7.1.37
All correspondence, after award of contract, shall be directed to:
Douglas R. Evans
P.O.Box 255
Weatherford, TX 76086
Phone:
(817) 598-4028
devans@weatherfordtx.gov
E-mail:
7.2
Design Review
7.2.1
WEATHERFORD MUNICIPAL UTILITY SYSTEM will conduct a design review
when the design and the layout drawings have been completed. The manufacturer shall
not start the manufacture of the transformer until the design review is complete and
until WEATHERFORD MUNICIPAL UTILITY SYSTEM has given written
concurrence that the design review has been successfully completed. This design
review will be completed approximately three (3) weeks after the design package
including approval drawings has been submitted to WEATHERFORD MUNICIPAL
UTILITY SYSTEM.
7.2.2
The manufacturer shall be prepared to hold a detailed design review at the factory.
When the design review is held, the manufacturer shall have the appropriate technical
personnel available to answer questions.
7.2.3
The manufacturer shall ensure that all design details including coils, magnetic circuit,
short circuit stresses and strengths, lead and cable sizes, temperature rise calculations,
cooling equipment, and hot spot temperature calculations have been completed prior to
the design review.
7.2.4
WEATHERFORD MUNICIPAL UTILITY SYSTEM will approve the methods used
for calculating the winding losses used during the temperature tests at the time of the
design review.
7.2.5
The manufacturer shall be prepared to discuss the methods used to calculate the
transformer hot spot temperatures during the design review. The hot spot temperatures
shall be calculated using one of the methods identified in C57.12.00-2000, Clause
5.11.1.1. Calculations using the hottest spot allowance are not acceptable.
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7.3
7.2.6
The manufacturer shall be prepared to discuss the gasket and gasket retention system
during the design review. The manufacturer shall be prepared to discuss leak rates and
durability of the gaskets.
7.2.7
Leakage Flux Loss and Heating Analysis: The manufacturer is expected to have
analysis programs and calculation methods to determine the leakage fields at different
points in the design and the resulting losses and temperatures. The heating in the core,
tie plates, core frames, tank walls, lead connections, etc. will be studied at the design
review.
7.2.8
The winding temperature rise shall be the limiting factor in loading this transformer.
The temperature rise in leads, LTC, bushings, or any other component shall not
determine the maximum loading of the transformer.
7.2.9
The temperature rises within the core are to be calculated. The maximum hot spot
gradient in the core at the worst-case excitation condition of 100% voltage at full load,
110% voltage at no-load, and 105% output voltage at full load and 0.8 power factor
shall not exceed 25°C.
7.2.10
The manufacturer shall calculate the short circuit forces and stresses that are generated
from the leakage magnetic fields. The manufacturer is expected to produce
documentation that supports the calculation methods, i.e. model tests, tests on full size
transformers, and experience in service.
7.2.11
The manufacturer shall provide substantiating data for the stress criteria used in this
design. For core form transformers the inner windings shall be analyzed for forced and
free buckling stresses. The bending stress between radial spacers and axial spacers are
to be provided. The compressive stress in radial spacers is to be calculated and the
maximum acceptable stress is 10000 psi (69 N/mm³). The calculations of the short
circuit stresses shall consider an offset between winding electrical centers of at least
0.5%.
7.2.12
The coil drying and sizing processes are to be provided. The transformer is to be
processed such that it remains tight during transportation, operation in service, and
after repeated faults in service. This is a design review subject.
7.2.13
The distribution of transient voltages in the windings shall be provided. The
calculations are to be made with a technique that considers both the capacitive and
inductive elements of the electrical network. Voltages within the windings, between
windings, and from winding to ground are to be calculated.
Shipping and Receiving
7.3.1
The manufacturer shall be responsible for manufacturing and shipping the transformer
such that it will withstand, without damage, all forces encountered during truck, water,
or rail shipment. When shipping by rail, the manufacturer shall use special cars
designed to provide maximum protection from shock.
7.3.2
Suitable recording devices on all shipping methods shall be attached before loading the
shipment for measuring both horizontals and the vertical components of shock.
Readings from these impact recorders shall be available to WEATHERFORD
MUNICIPAL UTILITY SYSTEM personnel upon receipt of equipment. Calibration
data showing that the impact recorders are in proper calibration shall be available to
WEATHERFORD MUNICIPAL UTILITY SYSTEM personnel at time of receipt of
equipment.
7.3.3
Unless specified otherwise by the manufacturer prior to shipment, transformer
experiencing shocks greater than 1G shall have a detailed internal inspection performed
by both the manufacturer and WEATHERFORD MUNICIPAL UTILITY SYSTEM
engineering representatives prior to acceptance. Manufacturer shall provide written
assurance on the integrity of the internal core and coil assembly following the
inspection if no corrective actions are necessary.
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7.3.4
Shipment shall be made F.O.B. destination with full freight allowed and prepaid. The
destination shall be on the transformer foundation at the job site. The transformer
destination shall be one of the five substations owned by: WEATHERFORD
MUNICIPAL UTILITY SYSTEM, all located in the city limits of
WEATHERFORD, TEXAS, 76086. The manufacturer is responsible for the
equipment and personnel needed to unload, reassemble, test, and fully prepare the
transformer. The manufacturer needs to provide two weeks notice of intent to deliver
to the WEATHERFORD MUNICIPAL UTILITY SYSTEM engineer. Deliveries will
only be accepted Monday through Thursday, on WEATHERFORD MUNICIPAL
UTILITY SYSTEM working days, unless other arrangements have been made.
7.3.5
The Respondent shall outline the personnel and procedures to be utilized by the
manufacturer and the manufacturer’s representatives to ensure that the transformer will
be safely unloaded in an energized substation environment.
7.3.6
The Respondent shall demonstrate to WEATHERFORD MUNICIPAL UTILITY
SYSTEM that all equipment, personnel, and sub-contractors involved with the
unloading process possess adequate and current insurance meeting WEATHERFORD
MUNICIPAL UTILITY SYSTEM requirements. These requirements include proof of
liability insurance of no less than one million dollars, and proof of workman’s
compensation insurance for all personnel on-site.
7.3.7
All equipment, personnel, and sub-contractors shall comply with WEATHERFORD
MUNICIPAL UTILITY SYSTEM safety regulations and oversight during the
unloading process.
7.3.8
Each unit shall be shipped filled with dry air at positive pressure. The dry air shall
have a dew point reading of -67.7° C or drier at 20° C ambient temperature.
7.3.9
Dew Point Measurements and Acceptance Criteria
If WEATHERFORD MUNICIPAL UTILITY SYSTEM does not exercise its right to take a
dew point reading; the manufacturer shall take a dew point reading without the presence of
WEATHERFORD MUNICIPAL UTILITY SYSTEM representative. The manufacturer
shall then e-mail to the WEATHERFORD MUNICIPAL UTILITY SYSTEM Project
Engineer, at devans@weatherfordtx.gov the results of the dew point measurements and the
dew point instrument calibration data to WEATHERFORD MUNICIPAL UTILITY
SYSTEM for approval. At a minimum, the manufacturer shall provide the actual dew point
measurement, the core and coil temperature when the dew point was taken and how the
temperature was determined, the date and time the transformer was filled with dry air, and
date and time the dew point reading was taken. The manufacturer shall not ship the
transformer until written permission from WEATHERFORD MUNICIPAL UTILITY
SYSTEM is received.
7.3.10
Dew Point Instrument
7.3.11
When WEATHERFORD MUNICIPAL UTILITY SYSTEM is present, the dew point
shall be taken with WEATHERFORD MUNICIPAL UTILITY SYSTEM dew point
instrument (Dewdicator Delux by Stephen’s Analytical, Inc.). The dew point taken
with WEATHERFORD MUNICIPAL UTILITY SYSTEM instrument shall be the
official dew point instrument used to determine if additional drying is needed.
7.3.12
Acceptable Dew Point
The acceptable dew point of the transformer shall be less than the allowable
maximum dew point value as calculated in the formula below:
Max. dew pt. in ° C ≤ [0.75 x (Winding Temp. in ° C - 80)]
WEATHERFORD MUNICIPAL UTILITY SYSTEM intent is to have a moisture
content of less than 0.5%
The above formula can only be used if the ambient temperature is above 10 Deg C.
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7.3.13
Measurement/Readings Before Shipment
All readings shall be made no earlier than twenty-four (24) hours after the transformer has
been disassembled for shipment and filled with dry air.
7.3.14
WEATHERFORD MUNICIPAL UTILITY SYSTEM reserves the right to take a dew
point reading of the transformer before it is shipped to WEATHERFORD
MUNICIPAL UTILITY SYSTEM.
7.3.15
The manufacturer shall provide two week notice to WEATHERFORD MUNICIPAL
UTILITY SYSTEM before the pre-shipment dew point reading.
7.3.16
If WEATHERFORD MUNICIPAL UTILITY SYSTEM exercises its right to take a
dew point reading, the manufacturer shall not open the transformer after the dew point
is taken for any reason without written permission from WEATHERFORD
MUNICIPAL UTILITY SYSTEM. If the manufacturer opens the transformer without
written permission from WEATHERFORD MUNICIPAL UTILITY SYSTEM will
take another dew point reading before the unit is shipped. The costs associated with
taking the second reading shall be paid by the manufacturer.
7.3.17
If WEATHERFORD MUNICIPAL UTILITY SYSTEM does not exercise its right to
take a dew point reading, the manufacturer shall take a dew point reading without the
presence of WEATHERFORD MUNICIPAL UTILITY SYSTEM representative. The
manufacturer shall then e-mail to the WEATHERFORD MUNICIPAL UTILITY
SYSTEM Engineer, at devans@weatherfordtx.gov the results of the dew point
measurement and the dew point instrument calibration data to WEATHERFORD
MUNICIPAL UTILITY SYSTEM for approval. At a minimum, the manufacturer
shall provide the actual dew point measurement, the core and coil temperature when
the dew point was taken and how the temperature was determined, the date and time
the transformer was filled with dry air, and date and time the dew point reading was
taken. The manufacturer shall not ship the transformer until written permission from
WEATHERFORD MUNICIPAL UTILITY SYSTEM is received.
7.3.18
If the dew point taken by WEATHERFORD MUNICIPAL UTILITY SYSTEM or the
manufacturer is greater than the maximum allowable dew point as determined by the
formula in Section 7.3.12, the manufacturer shall perform additional drying before the
transformer is shipped. WEATHERFORD MUNICIPAL UTILITY SYSTEM reserves
the right to refuse shipment if the transformer does not meet the specified criteria.
7.3.19
The manufacturer shall perform a DC core ground resistance measurement when the
transformer is ready for shipment. The results of this test shall be reported to
WEATHERFORD MUNICIPAL UTILITY SYSTEM’ Project Engineer prior to
shipment.
7.3.20
Measurement/Readings Before Off Loading the Transformer
All readings shall be made at the rail or job site before the transformer is off loaded from
the rail car or truck.
7.3.21
WEATHERFORD MUNICIPAL UTILITY SYSTEM’ Project Engineer or his
designee will be on site for monitoring the receiving of the transformer.
7.3.22
WEATHERFORD MUNICIPAL UTILITY SYSTEM’ Project Engineer or his
designee will review the impact recorder with the manufacturer. WEATHERFORD
MUNICIPAL UTILITY SYSTEM single point of contact or his designee will sign the
end of the impact recorder tapes to validate that the review was conducted. Failure of
the manufacturer to obtain this signature may result in the rejection of the transformer.
7.3.23
WEATHERFORD MUNICIPAL UTILITY SYSTEM’ Project Engineer or his
designee will take pictures of the transformer and its accessories for WEATHERFORD
MUNICIPAL UTILITY SYSTEM records.
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7.3.24
WEATHERFORD MUNICIPAL UTILITY SYSTEM reserves the right to take a dew
point reading and a DC core ground resistance measurement of the transformer before
it is off loaded from the rail car or truck.
7.3.25
Measurement/Readings Before the Transformer is Vacuum Processed
Vacuum processing and filling of the transformer shall not start until WEATHERFORD
MUNICIPAL UTILITY SYSTEM has taken a dew point reading of the transformer.
7.3.26
WEATHERFORD MUNICIPAL UTILITY SYSTEM’ Project Engineer or his
designee will take a dew point reading of the transformer. This reading shall be made
no earlier than 24 hours after the transformer has been assembled and filled with dry
air.
7.3.27
If the dew point taken either by WEATHERFORD MUNICIPAL UTILITY SYSTEM
or the manufacturer is greater than the maximum allowable dew point as determined by
the formula in Section 7.3.6.b, the manufacturer shall pay for any additional drying
before the transformer is filled. The procedure for drying the transformer shall be
approved in writing by WEATHERFORD MUNICIPAL UTILITY SYSTEM.
WEATHERFORD MUNICIPAL UTILITY SYSTEM reserves the right to refuse the
acceptance of the transformer if this approval is not obtained.
7.3.28
If additional drying of the transformer is required, the procedures in Section 7.3.12
shall be repeated before vacuum filling is started.
7.3.29
Final Field Acceptance
When the transformer has been assembled, vacuum processed, and filled with oil, and
tested, the manufacturer will complete, on the delivered and fully assembled transformer,
the tests listed in sections 7.3.30 through 7.3.33. The testing listed below in section 7.3.34
shall be done by the oil supplier prior to oil shipment. The final acceptance of the
transformer will be based on the results of these tests. If these test limits are not achieved,
the manufacturer shall find and correct the problem.
7.3.30
Take a DC core ground resistance measurement. This measurement shall be within the
limits specified by the manufacturer in its Instruction and Maintenance Manual.
7.3.31
Make the following insulation power factor measurements of the transformer:
138kV winding to 13.09kV winding overall in the Ground, UST, and Guard modes
noting the capacitance. Note all reads, milliamps, capacitance, and watts in both
directions at 10kV, high to low, then low to high, using a DOBLE power factor test
set or equivalent. All test data shall be in DOBLE format.
138kV winding to 13.09kV winding
138kV winding to ground
13.09kV winding to ground
The power factor shall be less than 0.5% when corrected to 20° C.
Take C1 and C2 power factor measurements and capacitance measurements of all
capacitance graded bushings. These values shall not deviate by more than 1% from
the values stamped on the nameplate. No power factor C1 or C2 shall be higher than
0.5%.
Make a “hot collar” type power factor test of all solid bushings. The value of each
solid bushing shall not deviate by more than 2% from the watts loss of the other solid
bushings on the transformer.
7.3.32
Make excitation tests at 10kV from 16R to 16L of the transformer windings. The
patterns generated by these tests shall match those that were made by the manufacturer
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at the factory. The current generated by these tests shall match the currents measured
by the manufacturer in the factory.
7.3.33
Make transformer turns ratio measurements from 16R to 16L of the transformer. All
ratios shall be within 0.5% of the transformer nameplate values.
7.3.34
Make the following oil tests:
Physical
Type of Test
Color (a)
Interfacial Tension,
Limits
0.5 max.
40 min.
Testing Standard
ASTM D-1500
ASTM D-971
(dynes/cm) 20° C
Specific Gravity
0.865-0.910 (60/60)
ASTM D-1298
Limits
Testing Standard
Electrical
Type of Test
Dielectric Breakdown
at 60 Hz:
VDE Electrodes,
(kV) 0.04 in. gap
(kV) 0.08 in. gap
35 min.
55 min.
ASTM D-1816
ASTM D-1816
Power Factor at 60 Hz, 20°C
0.05% max.
ASTM D-924
Power Factor at 60 Hz, 100°C
0.3% max.
ASTM D-924
Chemical
Type of Test
Total Acid Number,
(mg KOH/g)
Water Content
(PPM)
Neutralization Number,
(mg KOH/g)
Polychlorinated Biphenyls
(PCBs)
Limits
0.1 max.
Testing Standard
ASTM D-2440
5 max.
ASTM D-1533
0.015 max.
ASTM D-974
Not Detectable
EPA 608-1990
7.3.35
Estimates of the shipping weight of the largest piece, the shipping weight of the
heaviest piece, and the total shipping weight shall be transmitted to WEATHERFORD
MUNICIPAL UTILITY SYSTEM. The dimensions of the largest piece shall be
included.
7.3.36
Center of gravity markings for the transformer in its shipping arrangement and in its
completed form shall be indicated on all four sides of the transformer tank.
7.3.37
The manufacturer shall be responsible for packaging all parts for shipment so that they
will not be damaged and can be stored outside for a reasonable period of time. The
manufacturer shall be responsible for and make good any and all damage due to
improper preparation or loading for shipment.
7.3.38
Identification
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7.3.39
All shipment of material shall be marked with WEATHERFORD MUNICIPAL
UTILITY SYSTEM purchase order number. The manufacturer shall furnish a separate
packing list with each shipping crate. Packing lists shall also state that the transformer
is being shipped filled with dry air.
7.3.40
Immediately upon completion of packing the rail car or other transportation vehicle,
one (1) copy of the packing list shall be mailed to WEATHERFORD MUNICIPAL
UTILITY SYSTEM receiving agency:
Douglas R. Evans
P.O.Box 255
Weatherford, TX 76086
Phone:
(817) 598-4028
devans@weatherfordtx.gov
E-mail:
7.4
7.5
Installation
7.4.1
WEATHERFORD MUNICIPAL UTILITY SYSTEM will be responsible for making
up any external electrical connections. The manufacturer shall be responsible for
making all internal electrical connections, and for attaching all external accessories.
The manufacturer shall also be responsible for assembly, vacuum filling, and field
processing, and for unloading of the transformer and accessories and placing the
transformer on the foundation. The manufacturer shall present to WEATHERFORD
MUNICIPAL UTILITY SYSTEM an affidavit that the transformer is in all respects
CERTIFIED READY FOR ENERGIZATION.
7.4.2
The individual(s) sent to the destination site directing and supervising the placement,
assembly, and testing of the transformer shall be (a) direct, regular, full-time
employee(s) of the transformer manufacturer.
Warranty
The manufacturer shall provide a five (5) year warranty, including the internal and external paint
finish, against all manufacturing and design defects in the equipment, including all bushings and
related auxiliaries supplied under the purchase order. During the first year of this period the
warranty shall also cover the costs of removal, any freight by common carrier in full, and
reinstallation after repair. Costs of special, indirect, or consequential damages will be excluded.
7.5.1
The Supplier warrants that the items, at time of delivery, shall conform to the
OWNER'S specifications, the requirements of this Order, approved sample or samples,
if any, are free from defects in design, material, and workmanship, ARE
MERCHANTABLE, AND WILL BE FIT AND SUFFICIENT FOR THE PURPOSE
INTENDED. SUPPLIER SPECIFICALLY WARRANTS THAT TO THE EXTENT
HE KNOWS, COULD REASONABLY EXPECT TO KNOW, OR HAS BEEN
INFORMED OF THE PARTICULAR PURPOSE FOR WHICH THE ITEMS ARE
TO BE USED, THE ITEMS SHALL BE SUITABLE FOR SUCH PURPOSE. This
warranty shall remain in effect for a period of five years. At the OWNER'S option, the
Supplier shall promptly either repair or replace defective items after receipt of the
OWNER'S written notice of a defect, or shall immediately refund all monies paid
therefore.
7.6
Material Safety Data Sheets and Waste Reduction Notification
7.6.1
The Respondent shall furnish material safety data sheets (MSDS, OSHA Form 20) on
all chemicals and hazardous materials specifying generic and trade name of product,
product specification, full hazard information including receiving and storage hazards,
instructions and special equipment needed for handling. Information on approved
containers and instructions for the disposal of said material is also required. MSDS
shall be submitted with the PROPOSAL response. In addition, MSDS shall be
furnished with each shipment of chemicals and hazardous materials.
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7.6.2
7.7
Failure to include the applicable MSDS information as part of your PROPOSAL
response may subject the PROPOSAL responses to be disqualified from consideration
for award.
Service Bulletins
Service Bulletins shall be provided to WEATHERFORD MUNICIPAL UTILITY SYSTEM. The
manufacturer shall be responsible for providing any and all service bulletins/advisories on the
transformer provided after delivery. This is to be an ongoing process provided by the manufacturer
to keep WEATHERFORD MUNICIPAL UTILITY SYSTEM informed of any mechanical and/or
electrical problems which may cause breakdown or failure of the equipment, or more importantly,
jeopardize personnel working near the equipment. This service shall continue beyond the standard
warranty period and any fee for this service shall be included in the purchase price of the
transformer.
This correspondence shall be sent to:
Douglas R. Evans
P.O.Box 255
Weatherford, TX 76086
Phone:
(817) 598-4028
devans@weatherfordtx.gov
E-mail:
7.8
Loss Submittal Requirements
The manufacturer shall guarantee the following values:
7.9
7.8.1
The manufacturer shall state in the PROPOSAL at what LTC position the no-load
losses are guaranteed.
7.8.2
Load losses at 85° C when loading the transformer 138kV to 13.09kV at ONAN MVA
at the 1 raise LTC tap position.
7.8.3
The percent impedance’s corrected to 85° C from 138kV to 13.09kV on ONAN MVA
base.
Fall Protection
7.9.1 The transformer shall be provided with fall protection that meets or exceeds OSHA
requirements. Fall protection shall consist of a non-conductive tether pole. Tether pole
attachment shall be welded to the top of the transformer in the middle of the top cover.
Tether pole shall be provided.
36 of 36
FORM
CONFLICT OF INTEREST QUESTIONNAIRE
CIQ
For vendor or other person doing business with local governmental entity
OFFICE USE ONLY
This questionnaire reflects changes made to the law by H.B. 1491, 80th Leg., Regular Session.
This questionnaire is being filed in accordance with Chapter 176, Local Government Code
by a person who has a business relationship as defined by Section 176.001(1-a) with a local
governmental entity and the person meets requirements under Section 176.006(a).
Date Received
By law this questionnaire must be filed with the records administrator of the local governmental
entity not later than the 7th business day after the date the person becomes aware of facts
that require the statement to be filed. See Section 176.006, Local Government Code.
A person commits an offense if the person knowingly violates Section 176.006, Local
Government Code. An offense under this section is a Class C misdemeanor.
1
Name of person who has a business relationship with local governmental entity.
2
Check this box if you are filing an update to a previously filed questionnaire.
(The law requires that you file an updated completed questionnaire with the appropriate filing authority not
later than the 7th business day after the date the originally filed questionnaire becomes incomplete or inaccurate.)
3
Name of local government officer with whom filer has employment or business relationship.
Name of Officer
This section (item 3 including subparts A, B, C & D) must be completed for each officer with whom the filer has an
employment or other business relationship as defined by Section 176.001(1-a), Local Government Code. Attach additional
pages to this Form CIQ as necessary.
A. Is the local government officer named in this section receiving or likely to receive taxable income, other than investment
income, from the filer of the questionnaire?
Yes
No
B. Is the filer of the questionnaire receiving or likely to receive taxable income, other than investment income, from or at the
direction of the local government officer named in this section AND the taxable income is not received from the local
governmental entity?
Yes
No
C. Is the filer of this questionnaire employed by a corporation or other business entity with respect to which the local
government officer serves as an officer or director, or holds an ownership of 10 percent or more?
Yes
No
D. Describe each employment or business relationship with the local government officer named in this section.
4
Signature of person doing business with the governmental entity
Date
Adopted 06/29/2007
FORM
CONFLICT OF INTEREST QUESTIONNAIRE
CIQ
For vendor or other person doing business with local governmental entity
OFFICE USE ONLY
This questionnaire reflects changes made to the law by H.B. 1491, 80th Leg., Regular Session.
This questionnaire is being filed in accordance with Chapter 176, Local Government Code
by a person who has a business relationship as defined by Section 176.001(1-a) with a local
governmental entity and the person meets requirements under Section 176.006(a).
Date Received
By law this questionnaire must be filed with the records administrator of the local governmental
entity not later than the 7th business day after the date the person becomes aware of facts
that require the statement to be filed. See Section 176.006, Local Government Code.
A person commits an offense if the person knowingly violates Section 176.006, Local
Government Code. An offense under this section is a Class C misdemeanor.
1
Name of person who has a business relationship with local governmental entity.
2
Check this box if you are filing an update to a previously filed questionnaire.
(The law requires that you file an updated completed questionnaire with the appropriate filing authority not
later than the 7th business day after the date the originally filed questionnaire becomes incomplete or inaccurate.)
3
Name of local government officer with whom filer has employment or business relationship.
Name of Officer
This section (item 3 including subparts A, B, C & D) must be completed for each officer with whom the filer has an
employment or other business relationship as defined by Section 176.001(1-a), Local Government Code. Attach additional
pages to this Form CIQ as necessary.
A. Is the local government officer named in this section receiving or likely to receive taxable income, other than investment
income, from the filer of the questionnaire?
Yes
No
B. Is the filer of the questionnaire receiving or likely to receive taxable income, other than investment income, from or at the
direction of the local government officer named in this section AND the taxable income is not received from the local
governmental entity?
Yes
No
C. Is the filer of this questionnaire employed by a corporation or other business entity with respect to which the local
government officer serves as an officer or director, or holds an ownership of 10 percent or more?
Yes
No
D. Describe each employment or business relationship with the local government officer named in this section.
4
Signature of person doing business with the governmental entity
Date
Adopted 06/29/2007