Voltage testers

[beachbumjeremy]

I came across a problem today that I've never before encountered in a house. I was trouble shooting a circuit that was tripping as soon as it was turned on after some work in my house. I disconnected all the new work I had done, and went to the panel, with breaker off, and I read continuity from hot to ground, even after I disconnected the new work. I then turned the circuit on, and though I was reading continuity, the circuit didn't trip. I disconnected a few other devices on the circuit to see if I still had continuity hot to ground, and I did. I thought this strange, so I went to grab my fluke to test for continuity, ( I was using my greenlee) and the fluke would chirp one time, but wasn't constant. The greenlee would ring out as long as I held it. So I tested the fluke and when there was obvious continuity, it would remaining ringing till I removed the leads. On that circuit however, with the fluke, it would only chirp one time. So the fluke would chirp, the greenlee rang out clear as a bell, but when the circuit was on, it wouldn't trip. Only think I can figure is there was a minor slice in the romex and was making such lite contact with a ground that it wouldn't trip. Any other ideas?

 

[realolman]

I don't know about the chirping and ringing... Sounds too noisy for me. I'm assuming you want to know why you read continuity and the breaker did not trip??

Maybe a motor? Transformer? You were reading 0 ohms?

 

[Huntinmn]

I would check the breaker to see if it was good.

 

[beachbumjeremy]

Tested for continuity without breaker on, no motors or transformers, I isolated the homerun from the panel. seemed like the entire circuit from every isolated point to the other wanted to ring out for continuity for hot to ground, but only that one circuit.

 

[realolman]

How much current from the breaker when it is energized? How many ohms did it read when you checked for continuity? Are you saying you have it isolated to one single cable with nothing connected to it and it reads continuity? You're sure there isnt a wall wart power supply or fluorescent light or something still hooked up?

It sounds like there must be something wrong with the new work for one thing. If there was nothing wrong with it it doesn't seem it would add any additional load to cause it to trip as soon as it was energized.

 

[ptonsparky]

My Fluke meter, for continuity, is good for about 200 ohms. The Greenlee tester I use can squeal yet at 1 megaohm. Different testers for different purposes.