Type B - AC/DC Sensitive

Type B RCDs can detect sinusoidal AC, pulsating DC, composite of multi-frequency as well as smooth DC residual currents. In addition, tripping conditions are defined with different frequencies from 50Hz to 1kHz. In an AC electrical distribution network, a pure DC residual current can be mainly generated from three-phase rectifying circuits, but also from some specific single phase rectifiers.

Type B RCD are intended to be used for loads with three-phase rectifier, such as variable speed drives, PV system, EV charging station and medical equipment.