When a circuit breaker trips there is a fault. The circuit breaker is there to protect the wiring against overload. Either there is an overload or the circuit breaker is faulty. The former is the most likely cause, circuit breakers usually fail closed rather than trip for no reason. At one time we used to test all the circuit breakers for correct operation with a special tester. This test isn't included in MPDs these days. The CASA (Aussie regulatory authority) advice above is generally good but I'll pick two bones with them. First, carbon is not an excellent conductor. As every electrical/electronic specialist knows, carbon is a semi-conductor. However I'll admit that it conducts quite well in the heat of a fire. Secondly, CASA uses a landing gear circuit as an example, suggesting you leave it for the duration of the flight and close it for the landing. Well, there is always another way to get the gear down or tell if it is locked. If a tripped circuit breaker represents a fault, then closing it again is an even bigger fault. As they say, circuit breakers are there for a reason - to prevent electrical overloads causing a fire. So leave the d*mned things alone.
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Through difficulties to the cinema