Protection
Fault Current Calculator
Estimate prospective short circuit current at distribution boards.
Calculation engine in preparation
This calculator page is live and its inputs, results and export actions are being finalised. Formula notes and references below already apply.
Applicable references
National Electrical Code
Widely adopted code for safe electrical design, installation and inspection practice.
Source
Formula notes
- Fault level depends on source impedance, transformer impedance and cable impedance to the fault point.
Frequently asked questions
- Why is prospective fault current needed?
- Protective devices must have a breaking capacity at least equal to the prospective fault current at their point of installation.