4P 40A/10mA Residual Current Circuit Breaker

Principle of operation

The operating principle of this circuit breaker is based on the current balance principle. Under normal conditions, the currents entering and leaving the circuit should be equal in a line passing through a load. However, when there is an insulation fault in the line or when a human being comes into contact with the circuit, this can lead to current leakage, making the currents into and out of the circuit unbalanced. At this point, the current transformer inside the circuit breaker will detect this unbalanced current and convert it into an electrical signal. The electronic circuit will amplify, compare and process this signal, and when the signal reaches a preset threshold, i.e., when the residual current reaches or exceeds 10 milliamps, the circuit breaker will quickly cut off the circuit.

Main Features

High sensitivity: able to detect tiny leakage current (10 mA) and cut off the circuit in time to prevent electrical fires and electric shock accidents.

Fast response: once the leakage current is detected, the circuit breaker will cut off the circuit in a very short time (usually within tens of milliseconds).

Versatility: in addition to the basic leakage protection function, the circuit breaker may also have overload and short-circuit protection functions.

Easy to install and maintain: It usually adopts modularized design, which is easy to install and dismantle. Meanwhile, its simple internal structure makes it easy to maintain and overhaul.