SECTION 26 24 00 – PANELBOARDS, SWITCHBOARDS, AND TRANSFORMERS
PART 1 - GENERAL
1.01
SUMMARY:
A. This Section includes panelboards and dry-type transformers for low-voltage power and
lighting systems applications in the Administration Building and the Water Treatment
Building.
B. As a minimum, furnish and install the following in the electrical room of the Administration
Building:
1.
Two (2) 480V, 400A, 3-wire, 60-pole panelboards
2.
Two (2) 45kVA, 480-208/120V dry-type transformers
3.
Two (2) 208/120V, 125A, 34-wire, 42-pole panelboards
C. Furnish and install one (1) 120V, 100A, 2-wire UPS panelboard in the network room of the
Administration Building.
D. As a minimum, furnish and install the following in the electrical room of the Water Treatment
Building:
1.
Two (2) 480V, 225A, 3-wire, 60-pole panelboards
2.
One (1) 45kVA, 480-208/120V dry-type transformer
3.
One (1) 208/120V, 125A, 34-wire, 42-pole panelboard
E. Furnish and install one (1) 208/120V, 3-phase, 4-wire panelboard for the Guardhouse, sized as
required to accommodate all Guardhouse electrical loads.
1.
Provide a minimum of eight (8) spare 1-pole 20A breakers for Owner’s use.
E.F. As design develops, if building electrical systems require more capacity than is provided by the
panels above, Contractor shall design, furnish, and install additional panelboards as necessary.
F.G. Related Work Specified Elsewhere:
1.
Section 26 50 00 - Lighting, Receptacles, and Controlling Devices for lighting.
2.
Section 26 05 26 - Grounding.
1.02
REFERENCE STANDARDS:
American National Standards Institute (ANSI):
1.
C57 Series - Transformers, Regulators, and Reactors.
2.
C37.20 - IEEE Standard for Switchgear Assemblies Including Metal-Enclosed Bus.
National Fire Protection Association (NFPA):
1.
70 - National Electrical Code (NEC).
National Electrical Manufacturers Association (NEMA):
1.
AB1 - Molded Case Circuit Breakers and Molded Case Switches.
2.
ICS1 - Industrial Control and Systems.
3.
ICS2 - Industrial Control Devices, Controllers and Assemblies.
4.
ICS4 - Terminal Blocks for Industrial Use.
5.
PB1 - Panelboards.
6.
PB2 - Deadfront Distribution Switchboards.
7.
ST1 - Specialty Transformers (Except General-Purpose Type).
8.
250 - Enclosures for Electrical Equipment (1,000V Maximum).
Underwriters' Laboratories, Inc. (UL):
1.
50 - Enclosures for Electrical Equipment.
2.
67 - Panelboards.
3.
506 - Specialty Transformers.
4.
508 - Industrial Control Equipment.
5.
891 - Dead-Front Switchboards.
A.
B.
C.
D.
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SECTION 26 24 00 – PANELBOARDS, SWITCHBOARDS, AND TRANSFORMERS: continued
E.
1.03
A.
B.
Federal Specifications:
1.
FED-STD-595B - Colors Used in Government Procurement.
2.
W-P-115C - Panel, Power Distribution.
3.
W-C-375 - Circuit Breakers, Molded Case, Branch Circuit and Service, Type I, Series
Trip, Three Pole (10 through 100 Amperes).
SUBMITTALS:
Submit as specified in DIVISION 01.
Includes, but not limited to, the following:
1.
General arrangement and outline information.
2.
Schematic power diagrams.
3.
Wiring diagrams.
4.
Bills of material.
5.
Nameplate information.
6.
Protective device coordination curves.
PART 2 - PRODUCTS
2.01
A.
B.
C.
2.02
A.
ACCEPTABLE MANUFACTURERS:
Panelboards and Switchboards:
1.
General Electric Company.
2.
Cutler-Hammer.
Transformers:
1.
General Electric Company.
2.
Cutler-Hammer.
Mini Load Centers:
1.
Cutler-Hammer.
PANELBOARDS:
General:
1.
Heavy-duty type with voltage and ampere ratings as indicated.
2.
Enclosures of the following types:
a.
NEMA 12 – Dust tight for Administration Building, Guardhouse, and electrical
room of the Water Treatment Building.
b.
NEMA 4X – Stainless steel, watertight for all locations in the Water Treatment
Building other than the electrical room.
3.
Panelboards in code gage, hot-dipped galvanized sheet metal boxes with code gage steel
trim and finished with a rust inhibiting primer and light gray paint (formerly
ANSI Z55.1.61 No. 61).
4.
Hinged door with lock and catch combination in the front trim of all panelboards.
5.
Phenolic nameplate on front of panel engraved with the panelboard designation.
6.
Breakers with trip rating and number of poles as required. Breakers shall be installed to
fill out the capacity of each panelboard, which shall result in a minimum of 20% installed
spare breakers.
7.
Copper main buses of the capacity indicated.
8.
The short circuit current rating of the assembled panelboard or switchboard shall be equal
to or greater than the interrupting capacity of the highest rated branch breaker.
9.
Each breaker of each panelboard shall be individually padlockable to facilitate LOTO
activities.
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SECTION 26 24 00 – PANELBOARDS, SWITCHBOARDS, AND TRANSFORMERS: continued
B.
C.
D.
2.03
A.
B.
C.
D.
480VAC Panelboards:
1.
Rated 600Vac, 3-phase, 3-wire, 60-pole, with main breaker or lugs as indicated.
2.
Provide 100 ampere frame size bolt-on thermal-magnetic breakers with
noninterchangeable trip units.
3.
Provide 225-ampere frame size bolt-on thermal-magnetic breakers with interchangeable
trip units.
4.
Breakers shall have a minimum interrupting capacity of 65,000 rms amperes symmetrical
at 480V.
5.
Cutler-Hammer Type POW-R-LINE3 or General Electric Type CCB.
120/208VAC Panelboards:
1.
Rated 240Vac, 3-phase, 4 wire, 42-pole, solid neutral, with main breaker or lugs as
indicated.
2.
Provide 100 ampere frame size bolt-on thermal-magnetic breakers with
noninterchangeable trip units.
3.
Breakers shall have a minimum interrupting capacity of 10,000 rms amperes symmetrical
at 240Vac.
4.
Cutler-Hammer Type POW-R-LINE1 or General Electric Type AQ.
120VAC UPS Panelboard:
1.
Panelboard shall be 120/240VAC, 1-phase, 2-wire, solid neutral with 100 amp bus, with
main breaker, fusible branch circuit breakers, with 30 positions, and rated at 120VAC.
2.
Panels shall be constructed of galvanized and painted sheet steel.
3.
Panel shall have a minimum interrupting capacity of 22,000 rms amperes symmetrical at
120/240VAC.
4.
Each panel shall be populated with 20 single pole fast acting current limiting type circuit
breakers rated at 20 amps, 5 single pole fast acting current limiting type circuit breakers
rated at 30 amps, and space for 5 fast acting current limiting type circuit breakers.
5.
Branch fused disconnects:
a.
Device shall be UL listed, 600VAC with short circuit current interrupting rating of
100kA.
b.
Fuse and disconnect assembly shall be a finger-safe component with trim installed.
c.
Fuse and disconnect shall be mechanically interlocked so as not to allow fuse
removal while fuse terminals are energized.
d.
No special tools shall be required for fuse removal.
6.
Device shall provide fuse amp rating rejection at the following ampacities to ensure
continued circuit protection at the specified circuit rating: 15A, 20A, 30A, 40A, 50A,
60A, 70A, 90A, and 100A.
7.
Cooper Bussmann Quik-Spec type or Construction Manager-approved equal.
TRANSFORMERS:
Dry type with kVA rating as indicated.
Suitable for indoor or outdoor installation.
Encapsulated core and coils.
Noise level not to exceed NEMA ST1 standards as follows:
1.
0 9 kVA - 40 dB.
2.
10 50 kVA - 45 dB.
3.
51 150 kVA - 50 dB.
4.
151 300 kVA - 55 dB.
5.
301 500 kVA - 60 dB.
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E.
F.
Class H insulation with 115ºC maximum temperature rise in 40ºC ambient under continuous
full load operation.
480-120/208V, 3-phase, 60 hertz, delta-wye connected with taps as follows:
1.
Minimum of four 2-1/2% full-capacity taps, 2 above (FCAN) and 2 below (FCBN) 480V.
2.
General Electric Type ML for 3 15 kVA and Type QL for 30 kVA and larger or CutlerHammer Type EPT for 3 15 kVA and Type DT 3 for 30 kVA and larger.
PART 3 - EXECUTION
3.01
A.
B.
C.
D.
INSTALLATION:
General:
1.
Install at locations indicated including all necessary mounting and supporting materials.
2.
Locate and arrange with proper clearances from other equipment and material to obtain
good accessibility for operation and maintenance.
3.
Space away from walls or columns at least 1/4 inch to prevent surface moisture from
rusting the enclosure.
4.
Provide all necessary floor openings unless indicated as being provided by others.
5.
Clean all welds, scars, and abrasions and remove metal splatter, rust and foreign material
and apply organic zinc rich coating.
a.
Carboline - Carbozinc 859.
b.
International - Interzinc 52 HS.
c.
Tnemec - Tnemezinc 90-97.
Panelboards:
1.
Flush mount in finished areas and surface mount on walls or columns in all other areas.
2.
Install with top of panelboard approximately 6 feet above floor.
3.
Provide typed circuit directory in each panelboard indicating branch circuit loads.
4.
Rearrange circuit breaker locations to match the circuit sequence shown on the
panelboard schedules.
5.
Ground all neutral buses to the station ground system.
Switchboards:
1.
Shim so that unit is level, anchor to foundation with bolts cast in foundation or with cinch
anchors, and grout.
2.
Ground all neutral buses to the station ground system.
Transformers:
1.
Floor mount wherever possible unless otherwise indicated.
2.
Provide flexible conduit connections to minimize vibration and noise.
END OF SECTION 26 24 00
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