Full Load Current in Amperes:

Three Phase AC Motors

Motor Horsepower Motor Ampere Size Breaker Size Starter Heater Ampere Size Wire Size Conduit
1 230V
460 V		 4.2
2.1		 15
15		 00
00		 4.830
2.415		 12
12		 3/4"
3/4"
1-1/2 230V
460V		 6.0
3.0		 15
15		 00
00		 6.900
3.450		 12
12		 3/4"
3/4"
2 230V
460V		 6.8
3.4		 15
15		 0
00		 7.820
3.910		 12
12		 3/4"
3/4"
3 230V
460V		 9.6
4.8		 15
15		 0
0		 11.040
5.520		 12
12		 3/4"
3/4"
5 230V
460V		 15.2
7.6		 15
15		 1
0		 17.480
8.740		 12
12		 3/4"
3/4"
7-1/2 230V
460V		 22
11		 40
30		 1
1		 25.300
12.650		 10
12		 3/4"
3/4"
10 230V
460V		 28
14		 50
30		 2
1		 32.200
16.100		 10
12		 3/4"
3/4"
15 230V
460V		 42
21		 70
40		 2
2		 48.300
24.150		 6
10		 1"
3/4"
20 230V
460V		 54
27		 100
50		 3
2		 62.100
31.050		 6
10		 1"
3/4"
25 230V
460V		 68
34		 100
50		 3
2		 78.200
39.100		 4
8		 1-1/2"
1"
  1. Overcurrent device may have to be increased due to starting current and load conditions. See NEC 430-52, Table 430-152. Wire based on 75°C terminations and insulation.
  2. Overload heater must be based on motor nameplate and sized per NEC 430-32.
  3. Conduit size based on Rigid metal conduit with some spare capacity. For minimum size and other conduit types, see NEC Appendix C, or UGLY'S pages 102-122.