need help..fuse not tripping

Thread Starter


Joined Sep 18, 2006
hey frenz..
in my project i m using 4A MCB(miniature circuit breaker).
I am puting that in serial with my 20A DC power supply.
and i m drawing 15A current also(some times).
But the fuse is not tripping.
plz help me to troubleshoot.
i tried with 3 MCBs.same thing happened
Wat will b the problem?


Joined May 16, 2005
Circuit breakers take a bit of time to respond - the gizmo inside has to get hot enough to generate movement first.

You might try adding a current limiter or a fast-blow fuse.