Tronic Double Pole 100A 300mA RCCB

Our review

This is a residual current circuit breaker from Tronic, rated at 100 amps with a 300 milliamp sensitivity and a double pole layout. In plain terms, it watches the live and neutral conductors together and trips the circuit when it senses current leaking away, which is the kind of fault that can energise metalwork or give someone a sustained shock. The 300mA figure makes it better suited to protecting equipment and cables at the origin of an installation rather than as the final layer of personal protection, so it is often chosen for main incomers, sub-mains, pumps, workshops and small industrial boards where a larger leakage current is tolerable. Before buying, confirm three things: that your supply and cable can carry 100A, that your earthing arrangement and the earth leakage you expect match a 300mA device, and that the physical width and terminal layout fit your enclosure. Compare it with RCBOs, which combine overcurrent and earth leakage protection in one unit, and with lower-sensitivity or single pole alternatives. If you need each final circuit isolated independently, RCBOs usually win; if you want one device covering a whole board, this type is the simpler route. It is available on Sokonia.