I'm gonna go out on a limb here, but if there was an issue of a breaker not tripping - an EXTREMELY DANGEROUS situation - I would rather find out by testing live with a dead short then simply replacing a breaker or testing for high impedence and "assuming" or "hoping" the problem is corrected. In a situation like this, you really need to test live to make sure the electrical system functions as it was intended to. I mean really if a circuit breaker doesn't clear the fault, then what's the point?
If you're called in for this type of problem and you don't test live and a fault occurs that results in the building burning down or someone getting killed, guess who's assets are on the line? YOURS!
Of course, there are far more "elegant" ways of creating a dead short, like using a higher amperage breaker to create the short. For example, if you're testing a 20A circuit, you could use a 30A or even a 40A breaker for the dead short. If the test breaker trips and the panel breaker doesn't, obviously you've got a SERIOUS issue that absolutely needs to be corrected.
And if you damage a branch circuit as a result of a dead short all the better! A bad splice finally giving out, a nick in Romex now staying open, all better outcomes in the hands of someone who knows what they're doing and what to look for then failing in catastrophic way, arcing, heat buildup, open neutrals, etc.
Simply replacing an outlet that was damaged as a result of a breaker not tripping, in my opinion, would be negligence in the worst way in my opinion. That breaker should've tripped, what's the sense of a breaker panel then?
Liability is a REAL issue here.
Joe
