Max Capacitor kVAR at Motor Terminals (Self-Excitation Limit)
Returns the largest power-factor capacitor that can be switched with a motor before self-excitation overvoltage: magnetizing kVAR = sqrt(3) x V x no-load current / 1000 (NEMA MG-1 / IEEE 18), times a safety factor (default 0.90). The manufacturer's max-kVAR table by HP and speed governs; pair with the PF-correction tile and keep the smaller value.
Formula and source
magnetizing_kvar = sqrt(3) x V_ll x I_no-load / 1000; max_capacitor_kvar = safety_factor x magnetizing_kvar (default 0.90).
Maximum motor-terminal capacitor to avoid self-excitation, NEMA MG-1 and IEEE 18, by name.
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