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Protection Calculator

Comprehensive electrical protection analysis: OCPD sizing, device coordination, and relay settings per NEC requirements

OCPD Sizing Calculator

Calculate overcurrent protection device sizing per NEC Article 240

Standard OCPD Sizes (NEC 240.6)

15A
20A
25A
30A
35A
40A
45A
50A
60A
70A
80A
90A
100A
110A
125A
150A
175A
200A
225A
250A
300A
350A
400A
450A
500A
600A
700A
800A

Larger sizes available: 1000A, 1200A, 1600A, 2000A, 2500A, 3000A, 4000A, 5000A, 6000A