Sometimes I am asked if an older or dirty looking residential breaker panel is "safe". I have thought about devising some sort of CB tester to check to see if it will open on overload(not short circuits). I'm thinking various resistors rigged to draw 20, 25, 30 amps,etc. @ 120, 240 volts. You get the idea. Any thoughts, or are these devices commercially available? I'm not thinking about large scale CB testing, as done with specialized testers.
What aspect of the breaker do you wish to test? Whether it trips on short circuit?
Wire known good breaker in series with it and wire that to the ground. You can use an old 60 amp disconnect for this task, preferably one where you can swap breakers to get the size you want. You can use a light gage conductor to reduce the power of the bolted fault.
Dissipating the heat is a problem for any longer term test.
I once heard that in order for a circuit breaker to pass its testing it only has to work once and its considered to have done its job. I know in Canada we have a real problem with Federal Pioneer/Stab-Lok, you're lucky to get them to work once.
I would not recommend closing a disconnect on a knowen short circuit. With a setup like this you cant really tell what current actually tripped the breaker and if it was above the AIC. Used 120 volt test sets can be bought for less than $1000 that give actual current reading and have the timers built in. If you shop around you can get really good bargains. There are a lot of companies going in and out otf the breaker testing business. I think GE rents also rent test sets. You can also contact Mark Franks at http://www.atc-trng.com/ or Sales at www.avointl.com.
Originally posted by CanadianSparky: I once heard that in order for a circuit breaker to pass its testing it only has to work once and its considered to have done its job. I know in Canada we have a real problem with Federal Pioneer/Stab-Lok, you're lucky to get them to work once.
I have never had any success with FPE, in fact in my the inspectors will not approve any FPE for new construction and will dissuade its continuence and they almost insist on its replacement. The scary thing is that I just read about it was Air-Force one is protected by FPE. I guess thats why FPE cost 3x more than any other breaker