Circuit breaker finder

[flashlight]

I used to do a lot of work in data centers, turning off the wrong breaker is not an option. The deadly accuracy of the Amprobe is a must. The Ideal and Greenlee tracers are good, but not as good as the Amprobe.

About 10 years ago an old timer near retirement got in big trouble for shutting down computers on Wall Street.
His circuit finder ? A home-made "dead short" device.

 

[kwired]

About 10 years ago an old timer near retirement got in big trouble for shutting down computers on Wall Street.
His circuit finder ? A home-made "dead short" device.

Well you have to admit it won't shut off the wrong circuit, though it can possibly trip poor coordinated feeder breakers and kill the entire feeder instead of just the branch circuit.

 

[James L]

I was working on a remodel in a computer-heavy medical center, and re-used a half dozen existing circuits that were all in one j-box. 2 boats, all spare - I thought

No problems until I found the circuits with a trusty circuit finder. I turned off one of them and bunches of people were running around, down the halls screaming.

Turned out one of those circuits had been an emergency circuit, and somebody previously had used it in three or four other places for computer receptacles

 

[flashlight]

Well you have to admit it won't shut off the wrong circuit, though it can possibly trip poor coordinated feeder breakers and kill the entire feeder instead of just the branch circuit.

You're right! It won't shut off the wrong circuit, unless it shuts off all the circuits!

 

[kwired]

You're right! It won't shut off the wrong circuit, unless it shuts off all the circuits!

Had that happen to me inadvertently the other day. Gas station - relay panel for the pumps, we changed out a pump unit to a newer style that used just two wire digital signals instead of older analog signals, had to move that pump circuit to the adjacent control relay panel. Fuel equipment guy started disconnecting some leads, mostly his signal leads, I was going to move power leads a bit later. went to pull the "hot" through the conduit nipple and it arced and tripped breaker. A WTH moment. Then I discovered he was moving the leads from the wrong relay unit. I knew the correct one was turned off, though nobody tested with a meter .

So we straighten all that out then when we turn it on - nothing. This is older breaker that the switched neutral pole had given trouble and needs replaced, so I thought, maybe the ungrounded pole is now giving trouble. Nope no power at all - the earlier fault cleared the branch and the feeder breaker.

 

[David Henry]

I have Klein ET300 circuit breaker finders and this tool is awesome, I have had it for close to 2 years and have used it dozens of times.

 

[Davebones]

We use Amprobe CT326 . Very good for tracing . Used underground , breakers , wire's . I think this model has been replaced with newer version . ( AT-6010 )