How to find a short without a tripped breaker?

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Old 08-17-15, 10:21 PM
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How to find a short without a tripped breaker?

Hi,

I tried to replace a broken power switch. I was supposed to turn off the specific breaker first. But that switch does not have a individual breaker. If I want to cut the power, I will have to turn off the main power source, which means every electrical devices will be dead. I don't want to do that.
So I took the risk doing it with the power on, "bang" and some sparks: the power was off and so were a few lights and ventilation fan.
My question is how to trace the short in the situation where no breaker connected.
Thanks in advance.
z_johnq
 
  #2  
Old 08-17-15, 11:01 PM
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Ok... so after you shorted the switch what happened ? Did a breaker trip ?
Or are you saying nothing tripped and that part of the circuit is now dead?

Every device in the house MUST be on an individual breaker or you risk a fire hazard from overloaded/shorted wiring.
 
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Old 08-18-15, 06:02 AM
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"bang" and some sparks: the power was off and so were a few lights and ventilation fan.
You caused the short and you don't have to look for it. If the other devices such as fan and a few lights were off after "bang" I think you just found your breaker. Breakers are sometimes hard to tell if they are in the tripped position. Lightly move each handle and see if one feels loose.
 
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Old 08-19-15, 06:41 AM
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Thanks guys. Yes. I thought a breaker should get tripped after the "bang" but it was not as I looked at the power panel. I agree with PJMax that Every device in the house MUST be on an individual breaker or you risk a fire hazard... but it's not what I got.

Can a breaker get loosed? I'll test it and let you know. Thanks again.
 
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Old 08-19-15, 07:14 AM
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Is this a house that you own? How old is the electrical service?
 
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Old 08-19-15, 08:17 AM
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Is there a subpanel you haven't noticed. Could be some place it shouldn't such as in a cabinet or back of the closet. Maybe in an attic or crawl space.
 
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Old 08-19-15, 06:43 PM
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Certainly not EVERY device is not on an individual circuit,you have several devices on a circuit,hence the reason some other lights ,fan etc. went out.
Geo
 
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Old 08-20-15, 04:53 AM
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Yes, I own the house; it's not new no more, was built in 1980.

Thanks for the reminder that there might be another subpanel that I overlooked.

Btw, I checked and there is no loose breaker. None of them got tripped.
 
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Old 08-20-15, 04:56 AM
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I checked and there is no loose breaker. None of them got tripped
Then each must be checked with a multimeter, preferably analog, to be sure it reads correct voltage.
 
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Old 08-20-15, 05:03 AM
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No, I haven't done that yet. When you said 'analog', it meant non-digital, right? I'll let you know. Thanks for the quick return.
 
 

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