Circuit breakers providing short circuit protection for trailing cables shall be set so as not to exceed the maximum allowable instantaneous settings specified in this section; however, higher settings may be permitted by an authorized representative of the Secretary when he has determined that special applications are justified:
Conductor size AWG or MGM | Maximum allowable circuit breaker instantaneous setting (amperes) |
14 | 50 |
12 | 75 |
10 | 150 |
8 | 200 |
6 | 300 |
4 | 500 |
3 | 600 |
2 | 800 |
1 | 1,000 |
1/0 | 1,250 |
2/0 | 1,500 |
3/0 | 2,000 |
4/0 | 2,500 |
250 | 2,500 |
300 | 2,500 |
350 | 2,500 |
400 | 2,500 |
450 | 2,500 |
500 | 2,500 |
30 C.F.R. § 75.601-1