Function

Control electric circuits.

Protect people against indirect contacts and additional protection against direct contacts.

Protect installations against fire hazard due to insulation faults.

Residual current circuit breakers are used in housing, tertiary sector and industry.

Selection

1. Detectable wave form

- AC class

Tripping is ensured for slowly increasing sinusoidal AC residual currents.

- A class Tripping is ensured for sinusoidal AC residual currents and for pulsed DC residual currents, whether applied suddenly or increasing slowly.

- S, G/SI class

Tripping is ensured not only for sinusoidal AC residual currents but also for pulsed DC residual currents whether applied suddenly or increasing slowly. S, G/SI type with filters against spurious tripping caused by harmonics and transient surges. With the impact of 8/20us surge 3000A, this high immunity RCCB will still be in stable status.

2. Tripping sensitivity

10mA - precision instrument leakage protection and bathroom use.

30mA - additional protection against direct contact.

100mA - co-ordinated with the earth system according to the formula IΔn <50/R, to provide protection against indirect contacts; 300mA/500mA - protection against indirect contacts, as well as fire hazard.

3. Tripping time

Instantaneous - It ensures instantaneous tripping (without time-delay).

Short time delay - It ensures any tripping at least 10ms.

Selective - It ensures total discrimination with a nonselective RCD placed downstream.