CITY OF PALO ALTO
UTILITIES DEPARTMENT
SPECIFICATIONS FOR
AUTOMATIC CIRCUIT RECLOSERS
OVERHEAD TYPE
SPECIFICATION NO.: OE-13-08
DATE OF ISSUE: March 12, 2008
Reviewed by:
Power Engineer
Checked by:
Senior Power Engineer
Approved by:
Electrical Engineering Manager
SPECIFICATIONS FOR
AUTOMATIC CIRCUIT RECLOSERS
OVERHEAD TYPE
TABLE OF CONTENTS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
SCOPE......................................................3
STANDARDS..................................................3
RATINGS....................................................3
OPERATING MECHANISM........................................3
LEADS......................................................4
INSULATION.................................................4
GROUNDING..................................................4
PAINT FINISH/RECLOSER TANK.................................4
BUSHINGS AND TERMINALS.....................................5
RECLOSER CONTROL...........................................6
SUBMITTAL REQUIREMENTS.....................................7
DELIVERY...................................................7
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1.
SCOPE
These specifications cover electrical characteristics and mechanical features of three
phase, 60 hertz, automatic circuit reclosers for pole mounting in a horizontal
configuration on the City's high voltage (12470V), 3 phase, 3-wire overhead electric
distribution system. Equipment supplied by bidder under this specification shall include:
Automatic Circuit Recloser, Electronic Controller, Control Cable, and Pole Mounting
Rack.
2.
STANDARDS
Each recloser shall meet the applicable requirements of the latest edition of all IEEE and
NEMA Standards for automatic circuit reclosers and ANSI Standard C37.60, insofar as
such standards do not conflict with the requirements of these specifications. In case of
conflict, these specifications shall govern.
3.
4.
RATINGS
a.
Maximum Design Voltage 15.5 kV
b.
Nominal Operating Voltage 12.47 kV
c.
Basic Impulse Level 110 kV
d.
Maximum Continuous Current 600 amps
e.
Symmetric Interrupting Current 10,000 amps
OPERATING MECHANISM
a.
Current interruption shall take place in vacuum interrupters. Oil or SF6 gas shall
not be used for current interruption or insulation.
b.
The recloser shall be mechanically and electrically trip free.
c.
All three poles of the recloser shall be operated simultaneously by a solenoid
controlled spring operating mechanism. The solenoid shall provide energy for
closing the main contacts and for storing energy in the opening spring for a
tripping operation.
c.
The operating mechanism shall have a mechanical life of 2000 open/close
operations minimum. A mechanical operations counter shall be included, and
visible, on the bottom or front of the recloser.
d.
An operating handle shall be provided to manually trip and lock out the recloser.
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When in the tripped position, the operating handle shall be visible from the
ground and electrically disable any closing signal from the recloser control.
e.
5.
6.
Recloser mechanism open/close times shall perform consistently for control
cable lengths from 10 feet to 100 feet.
LEADS
a.
All leads from the interrupters to bushings shall be secured to prevent abrasion of
the insulation or weakening of the conductor due to vibration in shipment and in
service.
b.
Terminals, connectors, and current-carrying joints shall have accurately fitted
contact and shall be of ample stock for mechanical strength and electrical
conductivity. Riveted connections are not acceptable.
INSULATION
a. The recloser insulation shall consist of a solid dielectric. Oil or SF6 gas are not
acceptable.
b. The solid dielectric insulation shall provide complete encapsulation of the internal
vacuum interrupters. The insulation shall be bonded to the source and load side
terminals.
c. The solid dielectric shall not contain any environmentally hazardous or toxic
materials.
7.
GROUNDING
The recloser shall be supplied with a grounding connector suitable for connecting to #10
AWG solid - #2 AWG stranded conductors.
8.
PAINT FINISH/RECLOSER TANK
The recloser shall be capable of meeting the functional specifications shown below and
shall meet or exceed EEI Finishing Requirements Latest Revision.
a.
Tank Color:
Unless otherwise specified, the topcoat color shall be ANSI No. 70 sky gray.
b.
Salt spray (relates to coastal environments and/or presence of snow-melting
salts or fertilizers): Scribe to bare metal and test for 1500 hours in a 5% salt
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spray per ASTM B-117. Loss of adhesion from bare metal should not extend
more than 1/8 inch from the surface. Underfilm corrosion should not extend more
than 1/16 inch from the scribe.
9.
c.
Crosshatch adhesion (relates to adhesion after scratching of the finish): Scribe to
a bare metal a crosshatch pattern and test per ASTM D-3359, latest revision.
Use Method A for films thicker than 5 mils, Method B for films between 2-5 mils.
There shall be 100% adhesion to the bare metal and between layers.
d.
Impact (relates to transit and handling damage, and abuse by the public): Impact
the test panel with a 160 in-lb falling dart per ASTM D-2794. There should be no
cracking or chipping of the paint on the impact side of the test panel.
e.
Oil resistance (relates to probable contact with mineral oil): Immerse two test
panels in mineral oil (or other liquids as specified) for 72 hours, one at room
temperature (20 to 25 degrees C) and one at 100 to 105 degrees C. There shall
be no apparent changes, such as color shift, blisters, loss of hardness or
streaking.
f.
Exposure (relates to exposure to sunlight and rainfall, loss of gloss, color fading,
and chalking): Exposure for 500 hours per ASTM G-53 with a cycle for four
hours UV at 55 degrees C followed by four hours of condensation at 40 degrees
C. Loss of gloss as a result of this test should not exceed 50% per ASTM D-523.
g.
Abrasion Test (relates to wear encountered during installation): Test a panel
having the minimum dry build thickness (-0, +0.1 mil) using a CS-10 wheel, 1000
gram weight, per ASTM D-4060, latest revision. The number of cycles of
abrasion required to wear the coating through to the substrate shall be at least
3000 cycles.
h.
Recloser shall be fitted with lifting provisions to facilitate installation.
i.
Recloser shall be fitted with a stainless steel nameplate indicating, at a minimum,
serial number, date of manufacture, manufacturer, model, voltage rating,
continuous current rating, interrupting current rating, impulse level (BIL) rating, 3line diagram, and dielectric material type.
BUSHINGS AND TERMINALS
a.
The high voltage bushings may be of porcelain or polymer construction. Polymer
bushings shall be resistant to UV radiation and tracking.
b.
High voltage bushings shall have a minimum BIL of 110 kV and a minimum
creepage distance of 17 inches.
c.
High voltage terminals shall be clamp-type, suitable for connecting copper or
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aluminum conductors in the range of 1/0 AWG through 500 MCM.
10.
RECLOSER CONTROL
The recloser control shall be mounted in a weatherproof cabinet (minimum
NEMA 3 rating) which is capable of being padlocked. The cabinet shall be
supplied with a grounding connector suitable for connecting to #10 AWG solid
through #4 AWG stranded conductors.
a.
All printed circuit boards shall be conformal coated to prevent control malfunction
due to moisture.
b.
The control shall be fully functional over an ambient temperature range of –40
degrees C to 65 degrees C.
c.
The control shall be microprocessor based and include overcurrent protection for
all three phases and ground. Each phase and ground element shall have user
selectable time overcurrent curves including inverse, very inverse, extremely
inverse and definite time. The control shall also provide instantaneous or high
current trip protection for all three phases and ground. The control shall include
sensitive ground fault protection with an overcurrent pickup setting adjustable to
5 amps primary or less, and a definite time delay adjustable to 120 seconds or
longer. The control shall include the capability to program up to 3 reclosing
operations with reclosing and reset times from 0.2 to 120 seconds.
d.
The control shall include a digital metering package of Class 1 accuracy which
shall provide, at a minimum, the following information: instantaneous values of
voltage and current (by phase), load kVA, load kW, load kVAR, and demand
values of voltage, current, load kVA, load kW, and load kVAR. Metering data
shall be easily accessible from the control panel. The control shall be supplied
with inputs for three phase voltage.
e.
The control shall include a sequence of events recorder. The event recorder shall
trigger at fault inception and record time and date stamped fault information in
nonvolatile memory. Fault information shall include, at a minimum, voltage,
current, protection element status and recloser open/close status for each event.
f.
The control shall be capable of digital communications with the City’s SCADA
system through a communications port located in the control cabinet. The digital
communication protocol shall be DNP Version 3.0.
g.
A self-contained, user replaceable battery with AC charger shall power the
control. The battery shall be capable of supplying trip and control power for at
least 10 hours after loss of the AC power source. The control shall be capable of
monitoring battery health and initiating an alarm if the battery voltage drops
below a preset level.
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11.
12.
h.
The control cabinet shall be fitted with an AC-powered heater and thermostat
which are switched off when the control is running on battery power only.
i.
The supplied control cable shall be 40 feet in length and have separable
weatherproof connectors at both ends (recloser and control).
SUBMITTAL REQUIREMENTS
a.
The bidder shall furnish a list of Northern California utilities that have the quoted
recloser in service at this time, names of utility references, and contact
information. Palo Alto Utilities will only purchase this equipment from vendors
who have a history of reliable equipment and responsive customer service,
based on a combination of Palo Alto Utilities’ knowledge and reference checks.
This assessment is at the sole discretion of Palo Alto Utilities.
b.
The bidder shall submit drawings and sufficient documentation describing the
characteristics of the equipment to be furnished.
c.
The bidder shall submit a list of any exceptions to these specifications, and that
list shall be furnished with the bid submittal. If no exceptions are listed, Palo Alto
Utilities will assume the quoted equipment will conform completely to these
specifications.
d.
The bidder shall submit a bid price to include the cost of: Automatic Circuit
Recloser, Electronic Controller, 40 foot Control Cable, Recloser Pole Mounting
Rack, delivery of the quoted equipment to a designated location in Palo Alto,
California, and applicable sales tax (8.25% in Palo Alto).
DELIVERY
When the best responsive bid has been determined, the manufacturer or Supplier shall
provide a one day demo/training session along with a prototype unit at:
City of Palo Alto Municipal Service Center
3201 E. Bayshore Road
Palo Alto, CA 94303
ATTN: Norm Brown (call 650-496-6902 to schedule)
End of Specification
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