sEcTtoN 16273
MEDIUM VOLTAGE OIL FILLED PAD MOUNTED TRANSFORMERS
PART
1
1.01
SUMMARY
1.02
GENERAL
A.
Section includes requirements for:
1. Medium voltage outdoor liquid-filled pad mounted transformers.
B.
Related Sections:
1. The Contract Documents are complementary; what is called for by one is as
binding as if called for by all.
2. lt is the CONTRACTOR's responsibility for scheduling and coordinating the
Work of subcontractors, suppliers, and other individuals or entities performing
or furnishing any of CONTRACTOR's Work.
3. The following Sections are related to the Work described in this Section. This
list of Related Sections is provided for convenience only and is not intended to
excuse or othen¡vise diminish the duty of the CONTRACTOR to see that the
completed Work complies accurately with the Contract Documents.
a. Section 01300 - Submittals.
b. Section 16050 - General Requirements for ElectricalWork.
c. Section 16075 - Electrical ldentification.
d. Section 16950 - Field Electrical Acceptance Tests.
REFERENCES
A.
General:
1. Refer to Section 16050.
B.
lnstitute of Electrical and Electronic Engineers (IEEE):
1. C57.12.90 - Standard Test Code for Liquid-lmmersed Distribution, Power and
Regulating Transformers.
2. C57.12.26- Pad-Mounted, Compartmental-Type, Self-Cooled, Three-Phase
Distribution Transformers.
3. C57.12.28 - Standard for Pad-Mounted Equipment-Enclosure Integrity.
4. C57.12.29 - Standard for Pad-Mounted Equipment-Enclosure Integrity for
Coastal Environments
5. C57.12.00 - Standard General Requirements for Liquid-lmmersed Distribution,
Power, and Regulating Transformers.
C.
National Electrical ManufacturersAssociation(NEMA).
1. TR-1 - Transformers, Regulators, and Reactors.
2. TR-P9 - Security for Pad Mounted Equipment Enclosures.
D.
U.S. Department of Energy (DOE):
1. 10 CFR Paft431- Energy Effíciency ProgramforGertain Commercial and
lndustrial Equipment.
APRTL 2010 pw://Carolloi
FTNAL
16273-1
Documents/Client/IXFortiorth/8205410/Specifications/16273 (Final (cleâna))
8205A10
1.03 DEFINITIONS
A.
1.04
Refer to Section 16050.
SYSTEM DESGRIPTION
A.
Provide outdoor oil-filled, pad mounted transformers for operation on a 60 hertz
system with voltage and kilovolt-ampere ratings as indicated on the Drawings:
Suitable for continuous operation at full load at the project location and
elevation after applying any derating factors.
Pad mounted transformers shall be compartmental type, designed for outdoor
installation on a concrete pad.
1.
2.
1.05
SUBMITTALS
A.
B-
Furnish submittals in accordance with Sections 01300 and 16050Product Data:
Completeinstallationinstructíons.
Complete storage and handling instructions.
Kilovolt-ampere rating, including derating calculations.
Primaryisecondaryconnections.
Primary voltage and available taps.
Secondary voltage.
BIL rating.
Temperature rise.
Lightning arrestor data.
10. o/oZ,o/oX, %R, )UR.
11. Efficiency.
12. Gross weight.
13. Torque values for all bolted connections for secondary cable connections.
14. Manufacturer's suggested hi-potential test procedures and test levels for fieldtesting:
fnitialfield test.
Subsequent maintenance tests.
15. Certification from the manufacturer stating the transformer design complies
with ANSI C57.
16. Type of oil.
17. Gallons of oil.
18. Weight of oil.
19. Complete MSDS sheets.
1.
2.
3.
4.
5.
6.
7.
8.
9.
a.
b.
C.
Shop Drawings:
Complete detailed, dimensioned drawings showing the equipment being
furnished, with all pertinent information, including the following:
Dimensions and locations of conduit entrance windows.
Complete nameplate schedule, except impedance.
1.
2.
D.
a.
lnstallation lnstructions:
Provide anchorage instructions and requirements for the transformer based on
the seísmic requirements at the project site as indicated in Section 16050.
1.
APRIL 2010 -
FTNAL
pwJ/Carollo/Documents/Clienl/tX/Fort
16273-2
Worth/820541 0/Specifìcations/16273 (Fìnal (cleana))
8205A10
2.
1.06
E.
Operation and Maintenance Manuals:
1. Complete as-built dimensioned and scaled drawings for transformer.
2. Recommended periodic maintenance requirements.
3. Maintenance instructions including schedules, parts identification,
troubleshooting, assembly instructions, parts list, and predicted life of parts
subject to wear and deterioration.
4. Recommended field test levels and procedures before installation and for
maintenance purposes after being placed in service.
5. Periodic and preventative maintenance torque values for all bolts.
6. Copies of factory test reports.
F.
Test Reports:
1- Certified copies of test reports from factory tests.
G.
H.
Record Documents.
Refer to Section 16050.
Ship transformers to the iob site on a dedicated air ride vehícle that will allow the
CONTRACTOR to utilize onsite off-loading equipment:
1. Furnish temporary equipment heaters within the transformer to prevent
condensation from forming.
Refer to Section 16050.
WARRANTY
A.
I.IO
ManufacturerQualifications:
1. Manufacturer shall be in the business of regularly manufacturing the specified
transformers for minimum 10 years with satisfactory performance record.
PROJECT OR SITE CONDITIONS
A.
1.09
Refer to Section 16050.
DELIVERY, STORAGE, AND HANDLING
A.
B.
1.08
Calculations:
L Detailed calculations or details of the actual physicaltesting performed on the
transformers to prove the transformers are suitable for the seismic
requirements at the project site.
QUALITY ASSURANCE
A.
B.
1.07
Drawings and calculations stamped and signed by a Professional Engineer
registered in the State where the project is located.
Refer to Section 16050.
SYSTEM START UP
A.
Refer to Section 16050.
APRTL 2010 -
FINAL
pw://Carollo/Documents/ClienyTXFort
Worth/820541 0/Specificetions/1
16273-3
6273 (Final (cleana))
8205A10
B.
PART2
2.01
PRODUCTS
One of the following or equal:
Asea Brown Boveri - ABB.
General Electric GE.
Cooper Power Systems.
Schneider Electric/Square D Company.
1.
2.
3.
4.
MATERIALS
A.
B.
2.03
1.
2.
MANUFACTURERS
A.
2.02
Provide the services of a manufacturer's authorized representative:
lnspect installation before start-up.
Witnessenergization.
Windings:
Primary and secondary windings shall be high conductivity copper.
1.
lnsulating Fluid:
Envirotemp FR3.
lnsulating fluid shall meet or exceed the requirements of the appropriate ANSI
and ASTM fluid standards.
1.
2-
EQUIPMENT
A.
The transformer and associated terminal compartments designed and constructed
to be tamper-resistant:
'l
No externally removabre screws, borts, or other devices.
-
B.
Ratings:
3-phase, 60 hertz.
Self-cooled.
65 degree Celsius rise.
Primary voltage as indicated on the Drawings.
Primary connection as indicated on the Drawings.
Secondary voltage as indicated on the Drawingl.
Secondary connection as indicated on the Drawings.
Kilovolt-ampere rating as indicated on the Drawings.
PrimaryTaps:
Two 2-'ll2 percent above rated voltage.
Two 2-112 percent below rated voltage.
With no load tap changer externally operable with a hook stick.
Located in the primary compartment.
10. Basic impulse lnsulation Level (BlL):
a. 1.2 kV Class: 30 kV.
b.
2.5 kV Cfass: 45 kV.
c.
5.0 kV Class: 75 kV.
d. 8.7 kV Class: 75 kV.
e. 15 kV Class: 95 kV.
1.
2.
3.
4.
5.
6.
7.
8.
9.
a.
b.
c.
d.
APRIL 2O1O - FINAL
16273-4
pw://carollo/Documents/client/txFort worth/8205A1 0/specifications/1 6273 (Final (cleana))
8205A10
11.
12.
Sound Levels:
a. ln accordance with NEMA TR1.
b. Measurement procedure in accordance with ANSI C57.12.90.
Efficiency:
a. Transformers 2500 kVA and less shall have an efficiency rating in
accordance with DOE 10 CFR Part 431.
2.04 COMPONENTS
A.
TerminalCompartments:
1. Full-height, air filled primary and secondary terminal compartments with
hinged doors shall be located side-by-side separated by a steel barrier, with
the primary compartment on the left, complete with tamper resistant hardware.
2. Doors and compartment hood shall be removable:
a. Removable doorsill on compartments shall be provided to permit rolling or
skidding of unit into place over conduit stubs in foundations.
3. The doors in both the high voltage section and the low voltage section shall be
able to be latched in the open position.
4. The entire termínal compartment for the transformer shall be bolted to the
transformer so that the terminal compartment may be unbolted from the
transformer and the transformer removed without disturbing conduits that enter
the compartment from the side or top.
5.
6.
Minimum of 30 inches deep.
SecondaryCompartment:
a. The secondary compartment shall enclose the low voltage bushings and
provide for incoming cable from below the compartment.
b. This compartment shall also house:
1) Liquid level indicator.
2) Drain valve with sampling device.
3)
4)
5)
7.
8.
APRIL 2010 -
Dialtypethermometer.
Pressure relief valve.
Vacuum pressure gauge.
c. Door to low voltage section shall have a 3-point latching mechanism with
pad-locking provision.
Primary Compartment:
a. The primary line compartment shall enclose the high voltage bushings
and provide for incoming cables from below the compartment.
1) Coordinate primary bushing size with incoming cables size as
indicated on the Drawings.
b. This compartment shallalso house:
1) Dead front lightning arrestors.
2\ No-load tap changer.
3) Parking stands for 6 elbows.
c. The primary compartment shall be accessible only after the door for the
secondary compartment has been opened. The door shall be held closed
by a captive bolt; access to this bolt shall be provided only when the door
to the low voltage section is opened.
Primary Terminals:
16273-5
FTNAL
pwJi Carolloi Documents/ClienUTXFort Worlh/820541 0/Specifìcalionsi
1
6273 (Final (cleana))
8205410
a-
Shall be dead front construction, conforming with ANSI C57.12.26,
utilizing high voltage elbows for connectíons to primary cable and lightning
arrestors.
Terminal arrangement with 3-bushing wells:
3 for terminating primary power cables and for connecting lightning
arrestors.
Supporting structure within cabinet to support cables and eliminate
mechanícal stress on insulators,
Where indicated on the Drawings, provide the option for bayonet fuses on
the primary.
Secondary Terminals:
Four low voltage spade bushings with 2 holes for each cable, conforming
with ANSI C57.12.26.
Extend low voltage bushings as necessary to accommodate the cable
arrangement índtated on the Drawings oi ¡ndicated on the conduit
schedule:
Extension via a fully rated, tin plated, copper bus system braced to
withstand the available fault current.
Neutral brought out through an insulated bushing and externally grounded
to the tank with a removable ground strap.
Supporting structure within cabinet to support cables and eliminate
mechanical stress on insulators.
b.
1)
c.
d.
L
a.
b.
1)
c.
d.
B.
2.05
Core and Coil:
Vacuum Processed:
Energize windings under vacuum to heat coils and drive out moisture.
Core manufactured of grain-oriented silicon steel.
Coil insulated with B-stage, epoxy coated, diamond pattern, insulating paper
thermally cured under pressure.
1.
a.
2.
3.
ACCESSORTES
A.
B.
C.
LightningArresters:
High voltage dead front design for elbow connection.
Metal oxide varistor arresters.
Rating as indicated on the Drawings and/or consistent with the distribution
voltage.
1.
23.
Tank Ground Pads:
Two stainless steel pads, welded to the tank wall, with unpainted surfaces:
One pad in primary compartment.
One pad in secondary compartment:
lf additional load ground connections are required, a tin plated,
copper equipment ground bus shall be bolted to the pad.
1.
a.
b.
1)
Dial-TypeThermometer:
Direct stem mounted in a closed well so that the thermometer can be removed
without breaking the tank seal:
The well shall be threaded into a fitting that is welded to the transformer
tank wall.
1.
a.
APRIL 2010 -
FTNAL
pwJ/Cerollo/Documenfs/Client/tX/Fortïorrh/8205410/Specifrcations/16273
16273-6
(Final (cleena))
8205A10
2.
2.06
The thermometer shall have a slave hand which is moved by the indicating
hand to indicate maximum oiltemperature. The slave hand shall be externally
resettable.
D.
Sampling Device:
1. Allow for sampling of the transformer insulating fluid.
2. Threaded into a fitting that is welded to the transformer tank wall-
E.
Liquid Level Gauge:
L Dial-type liquid level gauge.
F.
Vacuum pressure gauge, 10 pounds per square inch gauge vacuum to plus
10 pounds per square inch gauge scale:
G.
Pressure Relief Device:
1. Located in the air space in the transformer tank to provide a method of
relieving internal tank pressure.
2. Self-relieving.
3. lndícating.
4. Operating Pressure: 10 within 2 pounds per square inch gauge.
H.
Nameplates:
1. Provide nameplate in accordance with Section 16075 and the following:
a- Provide complete nameplates identifying equipment, caution, voltage, etc.
b. Provide complete nameplates for both inside and outside of the
transformer terminal compa rtments.
c. Provide diagrammatic nameplate.
l.
J.
K.
L.
Bolted 8-inch (minimum) diameter round handhold on cover.
Lifting lugs at each corner of tank for lifting complete transformer.
Jacking facilities at each corner of base for jacking the complete transformer.
Base designed for rolling or skidding in either direction.
FABRICATION
A.
Tanks:
1. Constructíon: Sealed tank construction with welded cover. Permanently locate
an inorganic gasket between the cover and the tank flange during the welding
of the transformer cover to prevent the entrance of weld spatter into the tank.
2. Large handhole with bolted cover and protected with a weather cover.
3. 4lifting hooks.
4. Jacking pads.
5. Fluid sample valve.
6. Designed for 7 pounds per square inch gauge wíthout permanent distortion;
12 pounds per square inch gauge when silicone oil insulating fluid is specified.
APRIL 2010 -
FTNAL
pwJ/Carollo/Documents/ClienUT/r/Fort Worth/820541 0/Specifications/1
16273-7
6273 (Final (cleana))
8205A10
2.07
2.08
FINISHES
A.
ln accordance with ANSI C57.12.28 or ANSI C57 .12.29 for costal regions.
B.
Finish Color:
1. ANSI 61.
SOURGE QUALITY CONTROL
A.
Perform the following factory tests in accordance with ANSI/IEEE C57.12.90:
1. Routine tests as identified in ANSI/IEEE C57.12.90.
2. lnsulationresistance3. lnsulation power factor.
4. Sound test.
5. Before shipment, líquid-fill and pressure-test transformer for at least I hours at
the maximum operating pressure for detecting the presence of leaks.
B.
Verification of Performance:
1. Submit manufacturer's certified test results.
PART
3
EXECUTION
3.01
INSTALLATION
A.
B.
C.
3.02
Refer to Section 16050.
lnstall the equipment per the manufacturer's guidelines and submitted installed
instruction to meet the seismic requirements at the project site.
General:
1. Furnish concrete pad and all lugs, bolts, anchors, sealants, and other
accessories needed to complete the installation of the pad-mounted
transformer.
2. Assemble and install the transformer in the location and layout indicated on
the Drawings.
3. Perform work in accordance with manufacturer's instructions and shop
drawings.
4. Furnish components and equipment as required to complete the installation.
5. Replace any hardware lost or damaged during installation or handling.
6. Position the transformer so that the terminal compartment doors may be fully
opened, and all required working space and clearance requirements of the
National Electrical Code and the local building authorities are met.
FIELD G¡UALITY CONTROL
A.
Refer to Section 16950.
APRTL 2010 -
FINAL
pwJ/Carollo/Documents/ClienVTXFort
16273-8
Worth/820541 0/Specifìcetions/1ô273 (Final (cleana))
8205A10
3.03
ADJUSTING
A.
3.04
CLEANING
A.
3-05
Set the transformer taps as required to obtaín nominal output voltage on the
secondary terminals.
Refer to Section 16050.
PROTECTION
A.
Refer to Sectìon 16050.
END OF SECT¡ON
APRTL 2010 -
FTNAL
Brrr¡://Carollo/Documenþl0lieflt/tXFortWorth/8205A1OlSpecifcatbm/l6273
16273-9
(Fnal (cleffa))
8205A10
ApRrL 2010 -
FINAL
pw://Carollo/Documents/Client/IXFort-Worth/820541
16273-10
0/Specificafions/1 6273 (Final (cleana))
8205A10