Nec Ocpd Ratings: 450.3(A)
NEC overcurrent protective device (OCPD) ratings — standard ampere ratings for fuses and circuit breakers per Section 240.6(A), motor branch circuit protection per 430.52(C)(1), overload relay sizing per 430.32, and transformer OCPD sizing per 450.3
| nec section | record id | location type | primary circuit breaker pct | primary fuse pct | secondary hv circuit breaker pct | secondary hv fuse pct | secondary lv protection pct | standard | transformer rated impedance |
|---|---|---|---|---|---|---|---|---|---|
| 450.3(A) | 450.3A-any-z_6to10_primary_only | Any location | 400% | 300% | 250% | 225% | 125% | NEC (NFPA 70) 2017 Table 450.3(A) | More than 6% and not more than 10% |
| 450.3(A) | 450.3A-any-z_le6_primary_only | Any location | 600% | 300% | 300% | 250% | 125% | NEC (NFPA 70) 2017 Table 450.3(A) | Not more than 6% |
| 450.3(A) | 450.3A-supervised-any-no_secondary | Supervised locations only | 300% | 250% | Not required | Not required | Not required | NEC (NFPA 70) 2017 Table 450.3(A) | Any |
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