Live wire from 2 different breakers?!

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  #1  
Old 09-17-16, 04:36 PM
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Live wire from 2 different breakers?!

I'm getting the strangest reading from a circuit. I wanted to do some work on it so I turned off breaker 9, which is for sure this circuit.
When using a non contact voltage tester it was still live.
So I turned off breaker 3 and there was nothing.
I tried this again along 2 different receptacles 10ft apart and same issue.
Yet when I checked with a voltage meter, I get 120v only when breaker 9 is on.
How can I be getting a reading from the non contact tester from 2 different breakers?

Non contact
Breaker 3 off breaker 9 off no signal
Breaker 3 on breaker 9 off positive signal
Breaker 3 off breaker 9 on positive signal

Voltage meter
Breaker 3 off breaker 9 off 0v
Breaker 3 on breaker 9 off 0v
Breaker 3 off breaker 9 on 120v

The 2 different circuits don't cross wires anywhere and the receptacles are not split.
 
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Old 09-17-16, 04:40 PM
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When using a non contact voltage tester it was still live.
Please give it to your kid to play with. It can't be used for real testing. Pleas test with a multimeter, preferably analog.
 
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Old 09-17-16, 04:49 PM
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Yeah but they do pick up voltage. It has always worked before so I'm not sure how it could be picking up a reading here.
I know the multi meter gives the accurate reading as I used it to confirm.
But what could cause this with the non contact tester when no other wires are nearby? It's not that sensitive
 
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Old 09-17-16, 06:35 PM
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what could cause this with the non contact tester when no other wires are nearby
There was a post from a member who waved one at the ceiling and got a reading then panicked because they thought they had electric leaking into the room. Who knows. It doesn't mater except that garbage in is garbage out. As many times as non contact testers have been condemned in this forum I have to say I was a bit surprised by your post. We will be glad to help you when you have accurate readings.
 
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Old 09-17-16, 07:44 PM
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There have their uses
I have the accurate voltage readings above.
But the weird thing is is that no matter where along the circuit it picks up this voltage. If I hold it there and someone turns off the breaker of the different circuit, it stops beeping immediately, so it is picking up something.
 
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Old 09-17-16, 08:22 PM
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To determine if to breaker are cross connected turn off all 15 and 20 amp single pole breakers.
  • Turn on the first breaker. If neither circuit shows live using a meter or test light leave on.
  • Continue turning on till you find a breaker that does power the circuit.
  • Mark that breaker and turn it off.
  • Continue to turn breakers on till you find a second breaker that powers that circuit.
You now know the two breakers involved and start opening boxes. Look for obvious misconnections. If none leave the device dangling wires well separated and power up to check if there is still a cross over.
 
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Old 09-18-16, 04:10 AM
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Yes but with the volt meter only one breaker powers the circuit.
But I measured with the non contact in 3 different places along the circuit and it gives a signal when either breaker is on but only those 2 breakers.
Very odd.
What is cross connected... Split circuit?
 

Last edited by qwertyjjj; 09-18-16 at 04:41 AM.
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Old 09-18-16, 04:15 AM
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But I measured with the non contact in 3 different places along the circuit and it gives a signal when either breaker is on but only those 2 breakers.
Very odd.
Odd but meaningless. Go by the results from the better test instrument, the multimeter.
 
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Old 09-18-16, 05:28 AM
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The non contact is reading the field around another cable in close proximity.
 
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