Short-circuit current calculation | GorkyCAD Pro
Short-circuit current determines whether a breaker trips in time and whether the cable survives. GorkyCAD Pro calculates it automatically for every line.
Why short-circuit calculation matters
During a short circuit the line current spikes. If the breaker does not trip in time, the cable overheats and can catch fire. The calculation checks that the breaker trips and the cable survives.
', 'How GorkyCAD Pro calculates
Calculation follows IEC 60364 (impedance method): transformer, cables and busbar impedance. For each line the single-phase and three-phase fault current at the end of the line is computed.
- Total circuit impedance
- Fault current at the end of each line
- Breaker tripping time
- Cable thermal withstand check
Breaking capacity check
A breaker must have a breaking capacity (e.g. 6 kA) above the calculated fault current. GorkyCAD Pro checks this and highlights an error if the breaker does not fit.
', 'Export
Calculation results are included in the PDF set and used for project approval.
']FAQ
Which fault types are calculated?
Single-phase and three-phase short circuit.
Which standard?
IEC 60364 (impedance method).
Is breaking capacity checked?
Yes, the breaker is verified against the fault current.
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