The Metropolitan Water Reclamation District of Greater Chicago
General Specifications
SECTION 26 2416
PANELBOARDS
PART 1 - GENERAL
1.1
SUMMARY
A.
Section Includes:
1. Distribution panelboards.
2. Branch circuit panelboards.
3. Electronic grade panelboards.
4. Load centers.
5. Panelboard installation.
B.
Related Documents:
1. Applicable provisions of Division 00 – Procurement and Contracting Requirements
shall govern work of this specification section.
C.
Related Sections:
1. Applicable provisions of Division 01 – General Requirements shall govern work of
this specification section.
2. Applicable provisions of MWRDGC General and Detailed Technical Specifications
utilized for this project.
1.2
REFERENCES
A.
MWRD projects located within the City of Chicago limits shall conform to the City of
Chicago Building Code and MWRD projects located outside the City of Chicago limits
shall conform to Federal, State or Local building code requirements adopted by that
specific municipality.
B.
Institute of Electrical and Electronics Engineers (IEEE):
1. IEEE C62.41 - Recommended Practice on Surge Voltages in Low-Voltage AC
Power Circuits.
C.
National Electrical Manufacturers Association (NEMA):
1. NEMA AB 1 - Molded Case Circuit Breakers and Molded Case Switches.
2. NEMA FU 1 - Low Voltage Cartridge Fuses.
3. NEMA ICS 2 - Industrial Control and Systems: Controllers, Contactors, and
Overload Relays, Rated Not More Than 2000 Volts AC or 750 Volts DC.
4. NEMA ICS 5 - Industrial Control and Systems: Control Circuit and Pilot Devices.
5. NEMA KS 1 - Enclosed and Miscellaneous Distribution Equipment Switches (600
Volts Maximum).
6. NEMA PB 1 - Panelboards.
7. NEMA PB 1.1 - General Instructions for Proper Installation, Operation, and
Maintenance of Panelboards Rated 600 Volts or Less.
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PANELBOARDS
The Metropolitan Water Reclamation District of Greater Chicago
General Specifications
D.
International Electrical Testing Association (IETA):
1. NETA ATS - Acceptance Testing Specifications for Electrical Power Distribution
Equipment and Systems.
E.
National Fire Protection Association (NFPA):
1. NFPA 70 - National Electrical Code (NEC); Article 384.
F.
Underwriters Laboratories Inc. (UL):
1. UL 67 - Safety for Panelboards.
2. UL 1283 - Electromagnetic Interference Filters.
3. UL 1449 - Transient Voltage Surge Suppressors.
1.3
SUBMITTALS
A.
1.4
Section 01 3300 - Submittal Procedures: Requirements for submittals.
1. Shop Drawings:
a. Sufficient information, clearly presented, shall be included to determine
compliance with drawing and specifications.
b. Indicate outline and support point dimensions, voltage, main bus ampacity,
integrated short circuit ampere rating, circuit breaker and fusible switch
arrangement and sizes, wiring diagrams, and accessories.
2. Product Data: Submit catalog data showing specified features of standard products.
CLOSEOUT SUBMITTALS
A.
Section 01 7000 - Execution and Closeout Requirements: Requirements for closeout
submittals.
B.
Section 01 7839 - Project Record Documents: Record actual locations of panelboards
and record actual circuiting arrangements.
C.
Section 01 7823 - Operation and Maintenance Manuals: Submit spare parts listing;
source and current prices of replacement parts and supplies; and recommended
maintenance procedures and intervals.
1.5
QUALIFICATIONS
A.
1.6
Manufacturer: Company specializing in manufacturing products specified in this
section with minimum five (5) years documented experience.
MAINTENANCE MATERIALS
A.
Section 01 7000 - Execution and Closeout Requirements: Requirements for
maintenance products.
B.
Furnish two (2) of each panelboard key. Panelboards keyed alike to MWRDGC’s
current keying system.
2012 EDITION
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PANELBOARDS
The Metropolitan Water Reclamation District of Greater Chicago
General Specifications
PART 2 - PRODUCTS
2.1
DISTRIBUTION PANELBOARDS
A.
Substitutions: Product Description:
1. NEMA PB 1, circuit breaker type panelboard.
2. Furnish combination controllers as indicated on Drawings.
B.
Service Conditions:
1. Temperature: 120 degrees F maximum.
2. Altitude: 6500 feet above sea level.
C.
Panelboard Bus:
1. Hard drawn copper of 98 percent conductivity for current carrying components.
2. Ratings as indicated on Drawings.
3. Furnish copper ground bus in each panelboard.
D.
Minimum Integrated Short Circuit Rating:
1. 10,000 amperes rms symmetrical for 240-volt panelboards or as indicated on
Drawings.
2. 14,000 amperes rms symmetrical for 480-volt panelboards or as indicated on
Drawings.
E.
Fusible Switch Assemblies:
1. NEMA KS 1, quick-make, quick-break, load interrupter enclosed knife switch with
externally operable handle.
2. Furnish interlock to prevent opening front cover with switch in ON position.
3. Handle lockable in OFF position.
4. Fuse clips: Designed to accommodate NEMA FU 1, Class R or J fuses.
F.
Molded Case Circuit Breakers:
1. NEMA AB 1, circuit breakers with integral thermal and instantaneous magnetic trip
in each pole.
2. Furnish circuit breakers UL listed as Type HACR for air conditioning equipment
branch circuits.
G.
Molded Case Circuit Breakers with Current Limiters: NEMA AB 1, circuit breakers
with replaceable current limiting elements, in addition to integral thermal and
instantaneous magnetic trip in each pole.
H.
Current Limiting Molded Case Circuit Breakers:
1. NEMA AB 1, circuit breakers with integral thermal and instantaneous magnetic trip
in each pole, coordinated with automatically resetting current limiting elements in
each pole.
2. Interrupting rating 100,000 symmetrical amperes, let-through current and energy
level less than permitted for same size NEMA FU 1, Class RK-5 fuse.
I.
Controllers: NEMA ICS 2, AC general-purpose Class A magnetic controller for
induction motors rated in horsepower with the following components:
2012 EDITION
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PANELBOARDS
The Metropolitan Water Reclamation District of Greater Chicago
General Specifications
1. Two-speed Controllers: Include integral time delay transition between FAST and
SLOW speeds.
2. Full-voltage Reversing Controllers: Include electrical interlock and integral time
delay transition between FORWARD and REVERSE rotation.
3. Control Voltage: 120 volts, 60 Hertz.
4. Overload Relay: NEMA ICS 2; bimetal.
5. Auxiliary Contacts: NEMA ICS 2, 2 each field convertible contacts in addition to
seal-in contact.
6. Cover Mounted Pilot Devices: NEMA ICS 5, standard type.
7. Pilot Device Contacts: NEMA ICS 5, Form Z, rated A150.
8. Pushbuttons: Recessed type.
9. Indicating Lights: LED type.
10. Selector Switches: Rotary type.
11. Relays: NEMA ICS 2.
12. Control Power Transformers: 120 volt secondary, 150 VA minimum, in each motor
starter. Furnish fused secondary, and bond unfused leg of secondary to enclosure.
J.
Circuit Breaker Accessories: Trip units and auxiliary switches as indicated on
Drawings.
K.
Enclosure: NEMA PB 1, Type 1, 20-inches wide, cabinet box.
L.
Cabinet Front:
1. Surface door-in-door type, fastened with concealed trim clamps, screws, hinge and
latch, hinged door with flush lock, or metal directory frame, as shown on Drawings.
2. Finish in manufacturer's standard gray enamel.
2.2
BRANCH CIRCUIT PANELBOARDS
A.
Substitutions: Product Description: NEMA PB1, circuit breaker type, lighting and
appliance branch circuit panelboard.
B.
Panelboard Bus:
1. Copper, current carrying components, ratings as indicated on Drawings.
2. Provide copper ground bus in each panelboard and as indicated on Drawings.
C.
For non-linear load applications subject to harmonics furnish 200 percent rated, plated
copper, solid neutral.
D.
Minimum Integrated Short Circuit Rating:
1. 10,000 amperes rms symmetrical for 240-volt panelboards.
2. 14,000 amperes rms symmetrical for 480-volt panelboards.
E.
Molded Case Circuit Breakers:
1. NEMA AB 1, plug-on type thermal magnetic trip circuit breakers, with common
trip handle for poles, listed as:
a. Type SWD for lighting circuits.
b. Type HACR for air conditioning equipment circuits.
2012 EDITION
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PANELBOARDS
The Metropolitan Water Reclamation District of Greater Chicago
General Specifications
c. Class A ground fault interrupter circuit breakers as indicated on Drawings.
d. Do not use tandem circuit breakers.
F.
Current Limiting Molded Case Circuit Breakers:
1. NEMA AB 1, circuit breakers with integral thermal and instantaneous magnetic trip
in each pole, coordinated with automatically resetting current limiting elements in
each pole.
2. Interrupting rating 100,000 symmetrical amperes, let-through current and energy
level less than permitted for same size NEMA FU 1, Class RK-5 fuse.
G.
Enclosure: NEMA PB 1, Type as shown on drawing.
H.
Cabinet Box: Six (6) inches deep, 20-inches wide and for 240-volt and less
panelboards, 20-inches wide for 480 volt panelboards.
I.
Cabinet Front: Flush cabinet front with concealed trim clamps, concealed hinge, metal
directory frame, and flush lock keyed alike. Finish in manufacturer's standard gray
enamel.
2.3
ELECTRONIC GRADE PANELBOARDS
A.
Integral Surge Suppresser:
1. Component recognized in accordance with UL 1449 and UL 1283.
2. Independently tested with category C3 high exposure waveform (20 kV-1.2/50us,
10kA-8/20 us) in accordance with IEEE C62.41.
3. Provide copper bus bars for surge current path.
4. Construct using surge current modules (MOV based).
5. Each module fused with user replaceable 200,000 AIR rated fuses.
6. Status of each module monitored on front cover of panelboard enclosure and on
module.
7. Provide with audible alarm activated when one of surge current modules has failed.
8. Provide alarm on/off to silence alarm and alarm push-to-test switch to test alarm.
9. Locate switches and alarm on front cover of panelboard enclosure.
10. Meet or exceed the following criteria:
a. Maximum single impulse current rating not less than 320 kA for each phase.
b. Pulse Lift Test: Capable of protecting against and surviving 5000 IEEE C62.41
Category C transients without failure or degradation.
c. Clamping voltage not exceeding the following in accordance with UL1449:
Voltage
208Y/120
480Y/277
L-N
400 V
800 V
N-G
400 V
800 V
L-G
400 V
800 V
11. Provide response time no greater than five (5) nanoseconds for individual
protection modes.
12. Designed to withstand maximum continuous operating voltage (MCOV) of not less
than 115 percent of nominal RMS voltage.
2012 EDITION
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PANELBOARDS
The Metropolitan Water Reclamation District of Greater Chicago
General Specifications
13. Provide visible indication of proper suppresser connection and operation. Lights
indicate operable phase and module.
14. Provide minimum EFI/RFI filtering of 34 dB at 100 kHz with insertion loss ratio of
50:1 using Mil Std. 220A methodology.
B.
2.4
Panelboard:
1. UL 67 listed and TVSS device UL 1449 Component Recognized. TVSS device
meets UL 1449.
2. Provide panelboard markings with clamp voltage at TVSS terminals and clamp
voltage at panelboard line terminals.
3. Top or bottom feed as indicated on Drawings.
4. Provide circuit directory inside door.
5. Construct box of galvanized steel. Box size as indicated on Drawings.
6. Main bus constructed of copper and rated for load current.
7. Provide interior with branch circuit breakers.
8. Provide one 60 amp circuit breaker, with appropriate number of poles, as dedicated
disconnect for TVSS.
9. Provide 200 percent rated neutral assembly with aluminum or copper neutral bus.
10. Provide with insulated ground bus and safety ground bus.
11. Provide wiring gutters in accordance with NEC.
12. Field Connections to Panelboard: Main lug or main breaker type as shown on
Drawings.
13. Construct with flush mounted trim and NEMA Type 1, enclosure.
14. Provide with branch breaker positions and nominal current rating as indicated on
Drawings.
LOAD CENTERS
A.
Product Description: Circuit breaker load center, with bus ratings as indicated on
Drawings.
B.
Minimum Integrated Short Circuit Rating: 10,000 amperes rms symmetrical.
C.
Molded Case Circuit Breakers:
1. NEMA AB 1, plug-on type thermal magnetic trip circuit breakers, with common
trip handle for poles, listed as Type SWD for lighting circuits, Class A ground fault
interrupter circuit breakers as indicated on Drawings.
2. Do not use tandem circuit breakers.
D.
Enclosure: General Purpose.
E.
Box: Flush type with door, and pull ring and latch lock on door.
manufacturer's standard gray enamel.
Finish in
PART 3 - EXECUTION
3.1
EXISTING WORK
2012 EDITION
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PANELBOARDS
The Metropolitan Water Reclamation District of Greater Chicago
General Specifications
A.
Disconnect abandoned panelboards and load centers.
B.
Install blank cover for abandoned panelboards and load centers.
C.
Maintain access to existing panelboard and load centers remaining active and requiring
access. Modify installation or provide access panel.
D.
Clean and repair existing panelboards and load centers to remain or to be reinstalled.
3.2
PANELBOARD INSTALLATION
A.
Install panelboards and load centers in accordance with NEMA PB 1.1.
B.
Install panelboards and load centers plumb.
C.
Install recessed panelboards and load centers flush with wall finishes.
D.
Height: Six (6) feet to top of panelboard and load center; install panelboards taller than
six (6) feet with bottom no more than four (4) inches above floor.
E.
Install filler plates for unused spaces in panelboards.
F.
Provide typed or neatly handwritten circuit directory for each branch circuit panelboard
and load center. Revise directory to reflect circuiting changes to balance phase loads.
G.
Install engraved plastic nameplates in accordance with Section 26 0553 – Identification
for Electrical Systems.
H.
Install spare conduits out of each recessed panelboard to accessible location above
ceiling.
I.
Minimum Spare Conduits: Five (5) empty one (1) inch conduits. Identify each as
SPARE.
J.
Ground and bond panelboard enclosure according to Section 26 0526 – Grounding and
Bonding for Electrical Systems. Connect equipment ground bars of panels in
accordance with NFPA 70.
3.3
FIELD QUALITY CONTROL
A.
Section 01 4000 - Quality Requirements: Field inspecting, testing, adjusting, and
balancing.
B.
Inspect and test in accordance with NETA ATS, except Section 4.
C.
Perform circuit breaker inspections and tests listed in NETA ATS, Section 7.6.
D.
Perform switch inspections and tests listed in NETA ATS, Section 7.5.
E.
Perform controller inspections and tests listed in NETA ATS, Section 7.16.1.
2012 EDITION
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PANELBOARDS
The Metropolitan Water Reclamation District of Greater Chicago
General Specifications
3.4
ADJUSTING
A.
Section 01 7510 – Equipment Testing and Start-Up: Requirements for starting and
adjusting.
B.
Measure steady state load currents at each panelboard feeder.
C.
Rearrange circuits in panelboard to balance phase loads to within 20 percent of each
other.
D.
Maintain proper phasing for multi-wire branch circuits.
END OF SECTION
2012 EDITION
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PANELBOARDS