suggestions on troubleshooting a short.


  #1  
Old 11-02-17, 08:02 PM
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suggestions on troubleshooting a short.

CT.
old house. mix match of wiring.
some romex, some BX. some old BX without the separate ground wire and that brittle coating on the wires that falls off when you try to strip it.
my problem right now is, a breaker tripped. wont reset. i switched circuits with another breaker, old circuit would not let the new breaker reset, old breaker reset in the new circuit, so i assume that means the problem is in the circuit, not the breaker.
breaker buzzes when you try to reset it.
bulldog pushmatics.
i am assuming something broke and is causing a short.
i can only think of one labor intensive way to find the short and i was wondering if anyone knew of an easier way.
trace the wire from the breaker to the first light or outlet. disconnect the wire feeding everything after the first light or outlet. if breaker resets, follow the wire to the next light or outlet, repeat. if it doesn't reset, the short is in the first light or outlet or the wire from the breaker to the first light or outlet.
i cant test everything on the circuit, without tracing the wire, because i dont know what is on that circuit. i know which rooms, but some rooms have more then one breaker. if there are 4 out lets and a light in the room, all 5 might be on separate circuits with separate breakers.
so, is physically tracing the wire from the breaker and through every room the only way to find out where the problem is?
 
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Old 11-02-17, 08:27 PM
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If everything else is working...... you should know what is not and that's on the shorted circuit. If you have stuff haphazardly out all over the house you'll be in for a fun time.

Make it a priority to identify what is on what circuit in the house. When I'm called in to find a short.... I have to charge the customer for time identifying what he should have done.

Here's how I find shorts. I remove the black wire from the breaker. I find the neutral that belongs to that black wire. Remove it from the neutral bar. Using an ohmmeter.... check from black to white and from black to ground. That let's me know what kind of short I'm dealing with. Using an ohmmeter that has a low resistance scale I check the actual resistance of the short. Then I go from dead item to dead item. The lower the resistance measured..... the closer to the short. Consequentially the higher the resistance the further from the short.
 
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Old 11-02-17, 09:11 PM
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" If you have stuff haphazardly out all over the house you'll be in for a fun time. ".
not the whole house, about half.
something like 15 outlets, switches and lights in 4 rooms.
that is why i was hoping there was a better way then what i have planned.
i marked the breakers by the rooms they control, but everything in one room is not on the same breaker.
as far as i can tell, they wired the house based on how long the wire was that they had.
it was wired before there was a town or building codes.
farmers used to get drunk and wire houses back then.
i still have one 2 prong outlet in service.
so, i guess i am in for a fun time then?
maybe i will get lucky and the first light i check will be fried.
 
  #4  
Old 11-03-17, 04:28 PM
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first thing on the circuit is a light fixture. took it apart, pulled the wires out of the box to disconnect the fixture and it is that old type of BX. the insulation fell off.
i now think i will be better off if i just replace all the old BX on this circuit. i am just going to be creating more shorts as the BX falls apart when i move it.
 
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Old 11-03-17, 04:40 PM
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That old cloth covered BX was ok if undisturbed but trying to open a connection usually causes the insulation to crack or crumble off. Good move to replace what you can. You'll be gaining a grounded circuit too.
 
 

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