Circuit breakers
3 articles on circuit breakers.
04 Nov 2026 · 5 min read
RCD types AC, A, B: which one where
A Type AC residual current device is blind to the fault current modern electronics produce. The type letter is the difference between protection and a device that stays silent while someone is being shocked.
04 Nov 2026 · 4 min read
MCB breaking capacity: 6 kA or 10 kA?
Breaking capacity is not about the load, it is about the fault current the installation can deliver. Getting it wrong does not trip the breaker - it destroys it.
01 Nov 2026 · 5 min read
Reading a circuit breaker trip curve
A trip curve is the only honest document about what a breaker will do. Here is how to read the two axes, what B, C and D actually mean, and why a 16 A breaker trips on a 3 kW motor.