FAULT CURRENT PROTECTION 40A, 2P, 30 mA

Residual current protection

Rated current: 40 A
Leakage current: 30 mA
Rated breaking capacity: 6 kA
Number of poles: 2P
Rated voltage AC: 220-240 V
The residual current protection operates without the need to supply additional voltage to the actuating mechanism. The principle of operation consists of comparing the magnitudes of the currents flowing through the neutral and phase conductors. The conductors are wound on a toroid, which together with the secondary winding forms a summing measuring transformer. The power conductors are wound so that the magnetic fluxes generated by the flow of electric current cancel each other out.
When a fault occurs in the insulation of any of the conductors after the circuit breaker, or when a person comes into contact with live parts, the system becomes unbalanced and the magnetic fluxes cannot cancel each other out. The resulting magnetic flux then induces a voltage in the secondary winding, which drives a current through the electromagnet winding that is proportional to the leakage current. When the value of this current exceeds the limit value, the protection is triggered and the residual current circuit breaker disconnects from the supply network.