Dual element fuses having adequate current-interrupting capacity shall meet the requirements for short circuit protection of trailing cables as provided in § 75.601 , however, the current ratings of such devices shall not exceed the maximum values specified in this section:
Conductor size (AWG or MGM) | Single conductor cable | Two conductor cable | ||
Ampacity | Max. fuse rating | Ampacity | Max. fuse rating | |
14 | 15 | 15 | ||
12 | 20 | 20 | ||
10 | 25 | 25 | ||
8 | 60 | 60 | 50 | 50 |
6 | 85 | 90 | 65 | 70 |
4 | 110 | 110 | 90 | 90 |
3 | 130 | 150 | 105 | 110 |
2 | 150 | 150 | 120 | 125 |
1 | 170 | 175 | 140 | 150 |
1/0 | 200 | 200 | 170 | 175 |
2/0 | 235 | 250 | 195 | 200 |
3/0 | 275 | 300 | 225 | 225 |
4/0 | 315 | 350 | 260 | 300 |
250 | 350 | 350 | 285 | 300 |
300 | 395 | 400 | 310 | 350 |
350 | 445 | 450 | 335 | 350 |
400 | 480 | 500 | 360 | 400 |
450 | 515 | 600 | 385 | 400 |
500 | 545 | 600 | 415 | 450 |
30 C.F.R. §75.601-3