Short-Circuit Thermal & Dynamic Stability

Check I²t thermal duty and peak withstand against the equipment rating (IEC 60909 / IEC 62271).

Inputs

Prospective short-circuit current Iₖ A

Protective device operating time t s

Equipment 1-s withstand I_cw A

Rated withstand time t_rated s

Peak factor k —

Results

Note — I²t thermal duty uses rms current and the protective clearing time. The peak factor k = 2.55 assumes a symmetric aperiodic component; use the manufacturer's I_p / I_cw for the dynamic check. Verify with the equipment rating and a certified engineer.