Fault Current Calculator
Estimate available short circuit current
Conductor to Panel (optional)
Fault Current Results
At Transformer Secondary
--
At Panel (after conductor)
--
Transformer FLA
--
Transformer Impedance
--
Conductor Impedance
--
AIC Rating Requirements
| Available Fault | Min AIC Rating | Common Equipment |
|---|---|---|
| < 10,000A | 10 kAIC | Standard breakers |
| 10-22,000A | 22 kAIC | Commercial panels |
| 22-35,000A | 35 kAIC | Heavy commercial |
| 35-65,000A | 65 kAIC | Industrial |
| > 65,000A | 100+ kAIC | Special equipment |
Important Notes
This is an estimate only. For accurate fault current values, a formal short circuit study is required.
• Assumes infinite bus (utility contribution not limited)
• Does not account for motor contribution
• Per NEC 110.9, equipment must have AIC rating equal to or greater than available fault current