Ladd Spec updated Sheet 6 B53347.pdf
PDF 829 KB Posted
- Solicitation number
- 27-494DOT-FINAD-B-53347
- Issued by
- Dekalb County, Lee Center CDP, Illinois
About this file
This is an electrical specification sheet prepared by Prairie Engineers of Illinois, P.C. for the Illinois Department of Transportation (IDOT) District 3 Ladd Maintenance Yard Generator Installation project. The document provides detailed one-line electrical diagrams and technical specifications for the installation of a 96 kW/120 kVA natural gas standby engine generator with a 400-amp automatic transfer switch at the Ladd Maintenance Yard. The project includes installation of a NEMA 3R enclosed service disconnect switch, modifications to existing electrical panels (including new ground bars and breaker replacements), concrete generator pad construction measuring 10 feet by 5 feet by 6 inches thick, grounding field installation with three copper-clad grounding rods, conduit and conductor sizing specifications for above-grade and below-grade installations, and control wiring for the automatic transfer switch. Key electrical specifications include: 240/120VAC, 1-phase, 3-wire system configuration; (3) #4/0 and #4 ground conductors in 2-1/2-inch conduit below-grade; (2) sets of (3) #3/0 and #3 ground conductors in 2-inch conduit above-grade; and exothermic weld connections for grounding rod field connections 30 inches below finish grade. The sheet specifies coordination requirements with Ameren Illinois for electrical service modifications, temporary gas service disconnection/reconnection, and compliance with the 2023 National Electrical Code and NEC Section 240.21(B) for feeder tap installation.
The specification sheet establishes that all work must comply with manufacturer's written instructions for equipment installation, include legend plates identifying all service disconnects and panelboards, and incorporate weatherproof NEMA 3R-rated electrical enclosures. The document indicates that IDOT staff will perform surface material removal, backfill material and compaction, and aggregate sub-base replacement, while the contractor is responsible for equipment provision, programming, coordination, and utility connections. Demolition notes detail the removal of existing overhead service entrance conductors, electrical meter, weatherhead, and above-grade feeder circuitry while abandoning certain below-grade circuitry in place. The project requires coordination with utility providers regarding service modifications, temporary gas service connections, and transformer configurations. All work is subject to coordination with IDOT for trenching requirements, conduit installation protocols, and pad excavation specifications.
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Text version
KEYED NOTES:
SECURELY MOUNTED TO BUILDING.
PROVIDE 200A, 2-POLE, NEMA 3R ENCLOSED CIRCUIT BREAKER, 65,000 AIC MINIMUM,
SECURELY TO BUILDING AT 4'-0" INTERVALS.
PROVIDE (3) #4/0 AND #4 GROUND IN 2-1/2" CONDUIT ABOVE GRADE., MOUNTED
LISTED CONNECTORS.
PANELS "PP-1" AND "D0222 MDP". TAPS SHALL COMPLY WITH NEC 240.21(B) UTILIZING
EXTERIOR. PROVIDE TAPS IN FEEDER FROM ATS-1 FOR FEEDERS TO EXISTING
PROVIDE 36"x36"x8" NEMA 3R JUNCTION BOX MOUNTED SECURELY TO BUILDING
INSTALLATION WITH I.D.O.T.
COORDINATE TRENCHING REQUIREMENTS FOR BELOW-GRADE CONDUT
INSTALLATION WITH I.D.O.T.
COORDINATE TRENCHING REQUIREMENTS FOR BELOW-GRADE CONDUIT
AS HIGH AS PRACTICAL, FASTENED SECURELY TO BUILDING AT 4'-0" INTERVALS.
PROVIDE (3) #3 AND #8 GROUND IN 1-1/4" CONDUIT. MOUNT ABOVE-GRADE CONDUITS
AMEREN AS REQUIRED FOR ELECTRICAL SERVICE MODIFICATIONS.
COORDINATE DISCONNECTION/RECONNECTION OF ELECTRICAL SERVICE WITH
ON SHEET 8 FOR ADDITIONAL GENERATOR PAD INFORMATION.
REFER TO DETAIL 5 COORDINATE PAD INSTALLATION WITH CONDUIT INSTALLATIONS.
PAD SHALL EXTEND 1'-0" BEYOND LIMITS OF EQUIPMENT IN ALL DIRECTIONS.
REPLACEMENT.. COORDINATE PAD DIMESIONS WITH ACTUAL EQUIPMENT PROVIDED,
I.D.O.T. FOR PAD EXCAVATION REQUIREMENTS AND AGGREGATE REMOVAL AND
PROVIDE 10' +/- X 5' +/- X 6" THICK CONCRETE GENERATOR PAD.COORDINATE WITH
WELDS.
BELOW FINISH GRADE. CONNECTION TO GROUND RODS SHALL BE EXOTHERMIC
BARE STRANDED COPPER GROUND FIELD CONDUCTOR. GROUND FIELD SHALL BE 30"
PROVIDE 3/4" X 10'-0" COPPER CLAD GROUNDING ROD (TYP. OF 3) CONNECTED TO #2
GRADE TO PROTECT CONDUCTORS FROM PHYSICAL DAMAGE.
40 PVC CONDUIT TO TRIAD GROUND FIELD. SCHEDULE 80 PVC TO BE USED ABOVE
PROVIDE #2 INSULATED STRANDED COPPER GROUND CONDUCTOR IN 1/2" SCHEDULE
EXOTHERMIC WELDS.
BE 30" BELOW FINISH GRADE. CONNECTION TO GROUND RODS SHALL BE
#1/0 BARE STRANDED COPPER GROUND FIELD CONDUCTOR. GROUND FIELD SHALL
PROVIDE 3/4" X 10'-0" COPPER CLAD GROUNDING ROD (TYP. OF 3) CONNECTED TO
USED ABOVE GRADE TO PROTECT CONDUCTORS FROM PHYSICAL DAMAGE.
SCHEDULE 40 PVC CONDUIT TO TRIAD GROUND FIELD. SCHEDULE 80 PVC TO BE
PROVIDE #1/0 INSULATED STRANDED COPPER GROUND CONDUCTOR IN 3/4"
SECURELY TO BUILDING AT 4'-0" INTERVALS.
PROVIDE 2 SETS OF (3) #3/0 AND #3 GROUND IN (2) 2" CONDUIT ABOVE-GRADE. MOUNT
AND CONDUITS FOR EACH CIRCUIT PER MANUFACTURER'S WRITTEN INSTRUCTIONS.
FROM PANEL "PP-1" TO GENERATOR (GEN-1). PROVIDE BREAKERS, CONDUCTORS
CHARGER, ETC) AS REQUIRED PER MANUFACTURER'S WRITTEN REQUIREMENTS
PROVIDE MAINTENANCE CIRCUITS IN 1" CONDUIT (ENGINE BLOCK HEATER, BATTERY
CONDUIT/CONDUCTORS PER MANUFACTURER'S WRITTEN INSTRUCTIONS.
GENERATOR (GEN-1) FOR CONTROL SYSTEM. PROVIDE QUANTITY OF
WRITTEN INSTRUCTIONS FROM AUTOMATIC TRANSFER SWITCH (ATS-1) TO
PROVIDE CONTROL WIRING IN 1" CONDUIT OR AS REQUIRED PER MANUFACTURER'S
COORDINATE WITH I.D.O.T. FOR REQUIRED LIMITS OF REMOVAL.
MATERIAL AS REQUIRED FOR CONCRETE PAD AND CONDUIT INSTALLATION.
I.D.O.T. STAFF SHALL REMOVE AND REPLACE EXISTING AGGREGATE SUB-BASE
WIRES TO NEW GROUND BAR.
PROVIDE GROUND BAR IN PANEL. RECONNECT EXISTING BRANCH CIRCUIT GROUND
FROM NEUTRAL BAR AND RECONNECT TO NEW GROUND BAR.
EXISTING PANEL "D0222". DISCONNECT EXISTING BRANCH CIRCUIT GROUND WIRES
EXISTING POWER PANEL "D0222" TO REMAIN. PROVIDE NEW GROUND BAR IN
REFER TO PANEL SCHEDULE ON SHEET 7 FOR BREAKER REQUIREMENTS.
REMAIN. RECONNECT EXISTING BRANCH CIRCUIT GROUND WIRES TO GROUND BAR.
PROVIDE BREAKERS AS REQUIRED TO RECONNECT EXISTING BRANCH CIRCUITRY TO
TRENCHING, BACKFILL MATERIAL AND COMPACTION REQUIREMENTS WITH I.D.O.T.
WITH NON-SHRINK GROUT AND MAKE WATER/WEATHER TIGHT. COORDINATE
MAIN BREAKER IN TIRE SHED. SEAL ANNULAR SPACE AROUND CONDUIT PENETRATION
PROVIDE 100A, 240/120VAC, 1ϕ, 3W, NEMA 1, 12 CIRCUIT POWER PANEL WITH 100A
NEW GROUND BAR.
EXISTING BRANCH CIRCUIT GROUND WIRES FROM NEUTRAL BAR AND RECONNECT TO
BREAKER AND GROUND BAR IN EXISTING PANEL "D0222 BAY #2". DISCONNECT
EXISTING POWER PANEL "D0222 BAY #2" TO REMAIN. PROVIDE NEW 100A, 2-POLE MAIN
COMPACTION TO BE BY I.D.O.T.
BAR. ALL SURFACE MATERIAL REMOVAL/REPLACEMENT, BACKFILL MATERIAL AND
CIRCUIT GROUND WIRES FROM NEUTRAL BAR AND RECONNECT TO NEW GROUND
AND GROUND BAR IN EXISTING PANEL "D0223 5-BAY". DISCONNECT EXISTING BRANCH
EXISTING POWER PANEL "D0223 5-BAY" TO REMAIN. PROVIDE NEW 40A MAIN BREAKER
ADDITIONAL INFORMATION
MATERIAL AND COMPACTION TO BE BY I.D.O.T. REFER TO DETAIL 2 ON SHEET 8 FOR
MAIN BREAKER. ALL SURFACE MATERIAL REMOVAL/REPLACEMENT, BACKFILL
2-POLE ENCLOSED CIRCUIT BREAKER TO MAIN DISTRIBUTION PANEL "D0222 MDP"
PROVIDE (3) #4/0 AND #4 GROUND IN 2-1/2" CONDUIT BELOW-GRADE FROM NEW 200A,
(FUSED AT 400 AMPS), SECURELY MOUNTED TO BUILDING EXTERIOR.
PROVIDE 400A, NEMA 3R, HEAVY-DUTY SERVICE RATED FUSED DISCONNECT SWITCH
INSTALLATION AND LOCATION.
AUTOMATIC TRANSFER SWITCH WITH AMEREN REGARDING REQUIREMENTS,
(ATS-1), SECURELY MOUNTED TO BUILDING EXTERIOR. COORDINATE INSTALLATION OF
PROVIDE NEMA 3R, 400A, 240/120VAC, 1ϕ, 3W, 3-POLE AUTOMATIC TRANSFER SWITCH
DISCONNECTION.
GENERATOR. COORDINATE WITH AMEREN FOR TEMPORARY GAS SERVICE
PROVIDE PRESSURE REGULATOR, STRAINER AND SHUT-OFF VALVE IN GAS PIPING TO
CONTRACTOR TO FIELD VERIFY SIZE OF EXISTING NATURAL GAS SERVICE PIPING.
EQUIPMENT INSTALLED) TO EXISTING 2" NATURAL GAS SERVICE PIPING.
GAS FEED FOR GENERATOR (COORDINATE REQUIREMENTS WITH ACTUAL
WEATHERPROOF HOUSING. PROVIDE FITTINGS AS REQUIRED TO CONNECT NEW 2"
PROVIDE 96KW/120KVA STANDBY NATURAL GAS ENGINE GENERATOR (GEN-1) IN
BOND NEUTRAL AND GROUNDING LUGS IN THIS LOCATION PER NEC REQUIREMENTS.
X
DEMOLITION NOTES:
PANEL"D0222 MDP" TO PANEL "D0222".
REMOVE EXISTING FEEDER CIRCUITRY AND ABOVE-GRADE CONDUIT FROM
PANEL "D0223 5 BAY". ABANDON EXISTING BELOW GRADE FEEDER CIRCUITRY IN PLACE.
REMOVE EXISTING ABOVE-GRADE FEEDER CIRCUITRY FROM PANEL "D0222 MDP" TO
TIRE SHED PANEL. ABANDON EXISTING BELOW GRADE FEEDER CIRCUITRY IN PLACE.
REMOVE EXISTING ABOVE-GRADE FEEDER CIRCUITRY FROM PANEL "D0222 BAY #2" TO
EXISTING MAIN DISTRIBUTION PANEL "PP-1".
REMOVE EXISTING CONDUIT/CONDUCTORS FROM EXISTING 400A CT METER CABINET TO
REMOVE EXISTING GROUND FIELD OR ABANDON IN PLACE.
#2".
REMOVE EXISTING FEEDER CIRCUITRY FROM PANEL "D0222 MDP" TO PANEL "D0222 BAY
RECONNECTED TO NEW BREAKERS.
REMOVE EXISTING TIRE SHED PANEL, EXISTING BRANCH CIRCUITRY TO REMAIN AND BE
ENTRANCE CONDUCTORS WITH AMEREN.
CONDUCTORS. COORDINATE DISCONNECTION AND REMOVAL OF OVERHEAD SERVICE
REMOVE EXISTING ELECTRICAL METER, WEATHERHEAD, AND SERVICE ENTRANCE 1
X
TO REMAIN
PANEL "PP1"
DISTRIBUTION
, 3W MAIN ϕ1
AMP, 240/120V,
EXISTING 400
TO REMAIN
PANEL "252-A"
, 3W ϕ1
AMP, 240/120V,
EXISTING 100
100A
TO REMAIN
CT METER/CABINET
EXISTING 400 AMP
REMAIN
PANEL "D0222 MDP" TO
1Ø, 3W MAIN DISTRIBUTION
EXISTING 200 AMP, 240/120V,
REMOVED BY UTILITY COMPANY
TRANSFORMER TO REMAIN OR
EXISTING UTILITY POLE MOUNTED
TO BE REMOVED
EXISTING METER
200A
50A
40A
100A60A
REMAIN
BAY #2" TO
PANEL "D0222
, 3W ϕ1
AMP, 240/120V,
EXISTING 100
REMOVED
TO BE
CABINET
200A CT
EXISTING
(815)343-8303
ATHOMPSON4@AMEREN.COM
ELECTRIC & GAS: AMEREN ILLINOIS
LADD IDOT YARD;
UTILITY INFORMATION
TO REMAIN
MOUNTED TRANSFORMER
, 3W PAD ϕAC, 1120/240 V
EXISTING 50 KVA, 7200V TO
SCALE:
NO SCALE
EXISTING LADD MAINTENANCE YARD - ONE LINE ELECTRICAL DIAGRAM
GENERATOR DATA - LADD
KVA (MINIMUM)
VOLTAGE
FREQUENCY
PHASE
WIRE
POWER FACTOR
FUEL
AUTOMATIC TRANSFER SWITCH
SCALE:
NO SCALE
PROPOSED LADD MAINTENANCE YARD - ONE LINE ELECTRICAL DIAGRAM
ATS-1
400A
GN
6 79 8
TO REMAIN
MOUNTED TRANSFORMER
, 3W PAD ϕ120/240V, 1
EXISTING 50 KVA, 7200V TO
N G
L
NE
100A
400A
"PP-1" TO REMAIN
3W MAIN DISTRIBUTION PANEL
,ϕEXISTING 400 AMP, 240/120V, 1
TO REMAIN
PANEL "252-A"
, 3W ϕ1
AMP, 240/120V,
EXISTING 100
"D0222 MDP" TO REMAIN
3W MAIN DISTRIBUTION PANEL
, ϕEXISTING 200 AMP, 240/120V, 1
100A
50A
40A
MB
100A
100A
PANEL
3W TIRE SHED
, ϕ240/120V, 1
100 AMP,
TO REMAIN
PANEL "D0222"
, 3W ϕ1
AMP, 240/120V,
EXISTING 50
BAY" TO REMAIN
PANEL "D0223 5
, 3W ϕ1
AMP, 240/120V,
EXISTING 40
G N
200A
MB
100A
ONE LINE DIAGRAM NOTES:
EQUIPMENT IS REMOVED WHILE ALTERNATE SOURCE IS ENERGIZED".
SEPARATELY DERIVED SYSTEM) LABELED "WARNING SHOCK HAZARD EXISTS IF GROUNDING ELECTRODE CONDUCTOR OR BONDING JUMPER CONNECTION IN THIS
INCLUDE WEATHERPROOF ENGRAVED PHENOLIC LEGEND PLATE FOR EACH SERVICE DISCONNECT THAT HAS A BACKUP ENGINE GENERATOR SET (THAT IS NOT A 9.
INCLUDE COPPER EQUIPMENT GROUND BAR FOR MAIN DISTIBUTION PANEL "D0222 MDP" AND ALL SUBPANELS.8.
EQUIPMENT.
DISCONNECTS, EQUIPMENT, ETC. IDENTIFYING THE EQUIPMENT AND/OR NOTING THE RESPECTIVE INCLUDE LEGEND PLATES FOR ALL PANELBOARDS, LOAD CENTERS, 7.
WEATHERPROOF ADHESIVE AND/OR MACHINE SCREWS.
OR PHENOLIC MATERIAL, 1/4” HIGH BLOCK LETTERS ON A WHITE BACKGROUND. SECURE WITH LEGEND PLATES SHALL BE WEATHERPROOF ENGRAVED PLASTIC 6.
PHASE, 3 WIRE, NOTE MAIN DISTRIBUTION PANEL "PP1" IS BACKED UP BY WHOLE YARD STAND-BY GENERATOR”.
DISTRIBUTION PANEL IN BUILDING D0390 LABELED “PP1, FED FROM AUTO TRANSFER SWITCH, 240/120VAC, 1 FURNISH AND INSTALL A LEGEND PLATE FOR THE MAIN 5.
GENERATOR NEUTRAL IS BONDED TO GROUND AT THE MAIN SERVICE DISCONNECT”.
GENERATOR BREAKER LABELED “GENERATOR BREAKER, 400A, 240/120VAC, 1 PHASE, 3 WIRE” AND “NOTE FURNISH AND INSTALL A LEGEND PLATE FOR THE ENGINE 4.
-240/120VAC, 1 PHASE, 3 WIRE
OR-EMERGENCY SOURCE FROM WHOLE YARD STAND-BY ENGINE GENERAT
-NORMAL SOURCE FROM UTILITY TRANSFORMER THROUGH MAIN DISTRIBUTION PANEL "PP1"
-AUTO TRANSFER SWITCH
SWITCH AS FOLLOWS:FURNISH AND INSTALL LEGEND PLATE FOR AUTOMATIC TRANSFER 3.
TO GROUND AT SERVICE DISCONNECT”.
DISCONNECT LABELED “BUILDING MAIN SERVICE DISCONNECT”AND “NOTE GENERATOR NEUTRAL IS BONDED FURNISH LEGEND PLATES FOR THE BUILDING MAIN SERVICE 2.
SWITCH SHALL BE INSTALLED IN FULL COMPLIANCE WITH AMEREN REQUIREMENTS.SERVICE ENTRANCE EQUIPMENT, GENERATOR AND TRANSFER 1.
MB
40A
400A
GN
TO REMAIN
METER/CABINET
400 AMP CT
EXISTING
REMAIN
BAY #2" TO
PANEL "D0222
, 3Wϕ1
AMP 240/120V,
EXISTING 100
TO REMAIN
PANEL "D0222"
, 3W ϕ1
AMP, 240/120V,
EXISTING 50
REMAIN
5 BAY" TO
PANEL "D0223
, 3W ϕ1
AMP, 240/120V,
EXISTING 40
(GEN-1)120
240/120
60HZ
.8
NATURAL GAS
(ATS-1)NEMA 3R400A
GGG
101010
14 14
REMOVED
PANEL TO BE
TIRE SHED
1ϕ, 3W
AMP, 240/120V,
EXISTING 60
400A
G N
200A
SECTION COUNTY
ILLINOIS
TOTAL
SHEETS
SHEET
NO.RTE.
(011,037) ELE,EG,MG
USER NAME =
PLOT DATE = DATE
DESIGNED
CHECKED
DRAWN
REVISED
REVISED
REVISED
REVISED
F.A.
SHEET OF 8 SHEETS STA. TO STA.
CWB
5/1/2025
8/5/2026
CONTRACT NO.
SCALE:
STATE OF ILLINOIS
DEPARTMENT OF TRANSPORTATION
ONE LINE DIAGRAMS - LADD MAINTENANCE YARD
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8/5/2026
N/A BUREAU
professional design firm no. 184-005965 www.prairieengineers.com
Copyright Prairie Engineers of Illinois, P.C. 2023
Columbia, IL 62236
(217) 605-0403
404 N. Main Street
Prairie Engineers, P.C.
Expires: 11/30/2025 Date: 5/1/2025
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