Slow-Front Overvoltage, SFO IEC
Transient overvoltage usually unidirectional, with time to peak between 20 µs to 5 000 µs, and tail duration < 20 µs.
Transient overvoltage usually unidirectional, with time to peak between 20 µs to 5 000 µs, and tail duration < 20 µs.