30
Digidrive SK Technical Data
www.leroy-somer.com Issue Number: a
11.7 Use of earth leakage circuit breakers (ELCB)/residual current device (RCD)
There are three common types of ELCB/RCD:
Type AC
- detects AC fault currents
Type A
- detects AC and pulsating DC fault currents (provided the DC current reaches zero at least once every half cycle)
Type B
- detects AC, pulsating DC and smooth DC fault currents
•
Type AC should never be used with drives
•
Type A can only be used with single phase drives
•
Type B must be used with three phase drives