11
OPM-103
REV B
GENERATOR CIRCUIT BREAKER
This circuit breaker provides overload protection for the generator. You
power feeds from the load panel will connect to the open lugs on the
circuit breaker. The generator power feeds have already been wired
into one set of the lugs.
The following table gives you the circuit breaker size, lug wire sizes and
torque specifications. See actual breaker for additional information and
restrictions.
kW
Voltage
PH AMP Wire Capability
Lug Torque
20
120/240
1
85
#12 AWG - 2/0 AWG 50 in lbs
20
120/208
3
70
#12 AWG - 2/0 AWG 50 in lbs
20
120/240
3
70
#12 AWG - 2/0 AWG 50 in lbs
20
277/480
3
30
#14 AWG - #1/0 AWG 80 in lbs
30
120/240
1
125
#12 AWG - 2/0 AWG 50 in lbs
30
120/208
3
100
#12 AWG - 2/0 AWG 50 in lbs
30
120/240
3
100
#12 AWG - 2/0 AWG 50 in lbs
30
277/480
3
45
#14 AWG - #1/0 AWG 80 in lbs
45
120/240
1
175
#4 AWG - 300 MCM
250 in lbs
45
120/208
3
150
#4 AWG - 300 MCM
250 in lbs
45
120/240
3
750 #4 AWG - 300 MCM
250 in lbs
45
277/480
3
100
#14 AWG - #1/0 AWG 80 in lbs
65
120/240
1
250
#1 AWG - 600 MCM
375 in lbs
65
120/208
3
225
#4 AWG - 300 MCM
250 in lbs
65
120/240
3
225
#4 AWG - 300 MCM
250 in lbs
65
277/480
3
100
#14 AWG - #1/0 AWG 120 in lbs
90
120/240
1
350
#1 AWG - 600 MCM
375 in lbs
90
120/208
3
300
#1 AWG - 600 MCM
375 in lbs
90
120/240
3
300
#1 AWG - 600 MCM
375 in lbs
90
277/480
3
125
#14 AWG - #1/0 AWG 120 in lbs
For additional conductor sizes between the generator and the load.
Based on wire type and temperature rating. Wire has been derated for
40°C ambient temperature.
Wire Temperature Rating
CB
AMP
Cu Conductor
AI Conductor
kW Voltage PH
75°C
90°C
75°C
90°C
20 120/240 1
85
#3 AWG
#4 AWG
#1 AWG #2 AWG
20 120/208 3
70
#4 AWG
#6 AWG
#3 AWG #4 AWG
20 120/240 3
70
#4 AWG
#6 AWG
#3 AWG #4 AWG
20 277/480 3
30
#8 AWG
#8 AWG
#8 AWG #8 AWG
Wire Temperature Rating
CB
AMP
Cu Conductor
AI Conductor
kW Voltage PH
75°C
90°C
75°C
90°C
30 120/240 1
125
1/0 AWG #1 AWG
3/0 AWG 2/0 AWG
30 120/208 3
100
#2 AWG
#3 AWG
1/0 AWG #1 AWG
30 120/240 3
100
#2 AWG
#3 AWG
1/0 AWG #1 AWG
30 277/480 3
45
#6 AWG
#8 AWG
#4 AWG #6 AWG
Wire Temperature Rating
CB
AMP
Cu Conductor
AI Conductor
kW Voltage PH
75°C
90°C
75°C
90°C
45 120/240 1
175
3/0 AWG 2/0 AWG 250 MCM 4/0 AWG
45 120/208 3
150
2/0 AWG 1/0 AWG 3/0 AWG
2/0 AWG
45 120/240 3
150
2/0 AWG 1/0 AWG 3/0 AWG
2/0 AWG
45 277/480 3
70
#4 AWG
#4 AWG #2 AWG
#3 AWG
Wire Temperature Rating
CB
AMP
Cu Conductor
AI Conductor
kW Voltage PH
75°C
90°C
75°C
90°C
65 120/240 1
250 300 MCM 250 MCM 500 MCM 350 MCM
65 120/208 3
225
250 MCM 4/0 AWG 400 MCM 300 MCM
65 120/240 3
225
250 MCM 4/0 AWG 400 MCM 300 MCM
65 277/480 3
100
#2 AWG
# AWG
1/0 AWG #1 AWG
Wire Temperature Rating
CB
AMP
Cu Conductor
AI Conductor
kW Voltage PH
75°C
90°C
75°C
90°C
90 120/240 1
350 600 MCM 500 MCM (2) 250
600 MCM
90 120/208 3
300
500 MCM 350 MCM (2) 4/0
500 MCM
90 120/240 3
300
500 MCM 350 MCM (2) 4/0
500 MCM
90 277/480 3
125
1/0 AWG #1 AWG
3/0 AWG 2/0 AWG
For additional information on wire sizing refer to table 310-16 of the
National Electrical Code ANSI/NFPA 70.
