# Breaker tripping, troubleshooting



## chknkatsu (Aug 3, 2008)

okay, just to be clear i know i posted in the residential forum. but this is actually on a commercial job, but i figured i could get better responses here.

end of the day my foreman was having me trouble shoot a circuit that keeps tripping. 

single pole 20A circuit.
tested H-N = no continuity, H-G = no continuity.

when we turn the breaker on it trips like its having a dead short, changed breakers, same thing. the only thing that was on the circuit was a quad outlet which we disconnected at the splice box in the ceiling. all splice boxes were checked to make sure there were no shorts.

i tested for continuity both at the box and at the panel with the same result. what would be causing this that doesnt show up on a tester?


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## telsa (May 22, 2015)

Damaged tester...

Damaged leads...

Leads not fully inserted...

Over looked j-box...

Pinched hot at j-box lid...

Hot crossed over to another phase...

It'll be something.


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## chknkatsu (Aug 3, 2008)

telsa said:


> Damaged tester...
> 
> Damaged leads...
> 
> ...


tried two testers to just to be sure. 

we were testing wires, we opened up the splice before the quad outlets so no testing of outlets were involved.

a pinched hot should show SOMETHING on a tester right?

im going to see again tomorrow morning. anymore ideas are welcome


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## scotch (Oct 17, 2013)

Maybe use a merger to test with....your meter uses a 9v battery ?....maybe you need a higher voltage to see break over .


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## chknkatsu (Aug 3, 2008)

scotch said:


> Maybe use a merger to test with....your meter uses a 9v battery ?....maybe you need a higher voltage to see break over .


no megger on the job. my foreman originally told me to just take the quad and put it on another circuit. i would like to find the issue without using anymore resources otherwise he will squash it. i was using a 2x AA tester, im bringing in my better tester tomorrow to see. 

the breaker is tripping so quick i cant imagine why my tester cant see it. if it were a slow trip it would understand. but there is ZERO time between being on and tripping, the second you click it to ON it's already tripped.


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## readydave8 (Sep 20, 2009)

telsa;3725825
Hot crossed over to another phase...
It'll be something.[/QUOTE said:


> one of these probably is the answer


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## chknkatsu (Aug 3, 2008)

readydave8 said:


> one of these probably is the answer



like my Hot for my A phase is crossed with a Hot from B or C?


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## Jmcstevenson (Sep 11, 2010)

chknkatsu said:


> like my Hot for my A phase is crossed with a Hot from B or C?


Yeah I've seen phase to phase shorts that will either trip a main first or just one breaker on either phase but not the second breaker. Make sure you're not mixing your blues and your blacks. 

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## frenchelectrican (Mar 15, 2007)

chknkatsu said:


> no megger on the job. my foreman originally told me to just take the quad and put it on another circuit. i would like to find the issue without using anymore resources otherwise he will squash it. i was using a 2x AA tester, im bringing in my better tester tomorrow to see.
> 
> the breaker is tripping so quick i cant imagine why my tester cant see it. if it were a slow trip it would understand. but there is ZERO time between being on and tripping, the second you click it to ON it's already tripped.


There is couple way you can tell if you have hard short or crossed phase conductor.

First of all verify all the conductors to make sure it is matched up all the way.

Second unhook the conductor at the breaker and turn on the breaker to see if it stay on or still tripped without conductor. 

if stay on .,, 

get the Megger or use old school trick is get two 60 watts 120 volt standard bulb in series or get a 50 or 60 watt *240* volt bulb and hook it up between the breaker and the conductor you want to test. if the light become bright when you hit it on then ya got a short but if dim then you have bad connection or slow fault somewhere on the circuit. 

Even thru you did look at the junction box before the quad .,, unhook at the junction box to see if dont short it out. 

I am not too suprised there is a small nick of insulation will do this because with standard tester the voltage is not high enough to show it at all.
With the Megger it will show up because it will jump thru the bad gap.

That you will have to find it closely.


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## chknkatsu (Aug 3, 2008)

frenchelectrican said:


> There is couple way you can tell if you have hard short or crossed phase conductor.
> 
> First of all verify all the conductors to make sure it is matched up all the way.
> 
> ...


thats a pretty neat trick. unfortunately we ended up abandoning that conductor and just put the outlet on another existing circuit.


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## Switched (Dec 23, 2012)

chknkatsu said:


> thats a pretty neat trick. unfortunately we ended up abandoning that conductor and just put the outlet on another existing circuit.


What do you mean you abandoned the conductor? You left it in the condition it was in and just stole power from another location?


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## telsa (May 22, 2015)

chknkatsu said:


> thats a pretty neat trick. unfortunately we ended up abandoning that conductor and just put the outlet on another existing circuit.


I've never walked away from a circuit fault.

I don't think I could do it. 

Then, again, I have too many tools. :thumbsup:

[ EVERY e-firm I ever worked for threw me at their worst nightmares -- almost instantly. ]

[ Call it a weakness, but I've been able to resolve circuit issues -- every single time. Once this meant $400,000 to my employer ! I didn't find out this till much later.]

[ Another time a charge back of $65,000 bounced from my employer to another sub. Yep. I'm the man responsible.]

[ So, I'm biased.]

[ Not only is my stuff squared away, it's done so in good time -- sometimes -- in amazing time.]


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## sbrn33 (Mar 15, 2007)

Now way I leave it that way. Hell I would fix it on my own time if I had to, that would bug me for the rest of my life.


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## Jmcstevenson (Sep 11, 2010)

I love starting TI's and seeing breakers/cap'd wires in the panel with DO NOT ENERGIZE on white tape. Once they actually typed it onto the directory.. if it's someone else's work and you bid tight then I get not investigating. If it's your own work you have a responsibility to at least remove it. 


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## sbrn33 (Mar 15, 2007)

readydave8 said:


> one of these probably is the answer


I doubt this. Most of time that happens both breakers trip.


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## macmikeman (Jan 23, 2007)

telsa said:


> I've never walked away from a circuit fault.
> 
> I don't think I could do it.
> 
> ...



No way I'm gonna let a 465,000 windfall land in my lap and not compensate the electrician employee who brought in that fish to the tune of at least 50%.


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## Majewski (Jan 8, 2016)

Even I am bothered now not knowing wtf the issue was!


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## chknkatsu (Aug 3, 2008)

Switched said:


> What do you mean you abandoned the conductor? You left it in the condition it was in and just stole power from another location?


i took it from another circuit coming out of the same conduit.

out of the panel i had a BK/WT, RD/WT, and BL/WT. we abandoned the BL/WT and took power from the BK/WT.

i cant remove the conductor since its part of a Quik-Pull bundle that's been wrapped together. I would have liked to solve the issue but its not my call


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## chknkatsu (Aug 3, 2008)

Majewski said:


> Even I am bothered now not knowing wtf the issue was!


me too, but it is what it is:001_unsure:


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## PlugsAndLights (Jan 19, 2016)

chknkatsu said:


> me too, but it is what it is:001_unsure:


Learn what you can and move on. It's the foreman's call. 
P&L


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## readydave8 (Sep 20, 2009)

sbrn33 said:


> I doubt this. Most of time that happens both breakers trip.


good point


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