Finding the location of a short in EMT

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Hv&Lv

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Engineer/Technician
At first, I thought the OP was saying that one conductor was too short for the pull.

In my opinion, the wire should be pulled back from where it started, the bad wire repaired or replaced (better) and re-pulled.

It would be prudent to pull a mouse through and then inspect it carefully to make sure the new wire doesn't get damaged.
I would be afraid to repair the wire. The sidewall pressure is enough to cause a wire to drop from under a Kellam or tie then I’m sure it will pull the repair from the bad spot.
im for replacing personally.
just my opinion... it seems like more work to find, cut a box, repair or splice, and finish pull than to pull it all back out and start over.

but then again, I’m not there...
 

480sparky

Senior Member
Location
Iowegia
I can't find faults in a PVC conduit if there is a bare cu pulled in it. IDK how the heck it could be done in EMT....

If it's shorted to the conduit, you use a fault locator connected to the faulted conductor and the EMT. As I stated, the EMT cannot be connected to anything grounded.
 

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
If it's shorted to the conduit, you use a fault locator connected to the faulted conductor and the EMT. As I stated, the EMT cannot be connected to anything grounded.
With the Amprobe tracer, the emt can remain grounded, unlike fault locators and underground tracers, it does not inject a frequency that spreads everywhere. It draws a current pulse at a set frequency that’s picked up by the receiver. It will not work on open circuits due to that. When you reach the end of the current loop, the signal stops, and there is your short.
 

480sparky

Senior Member
Location
Iowegia
With the Amprobe tracer, the emt can remain grounded, unlike fault locators and underground tracers, it does not inject a frequency that spreads everywhere. It draws a current pulse at a set frequency that’s picked up by the receiver. It will not work on open circuits due to that. When you reach the end of the current loop, the signal stops, and there is your short.

Fault locators don't inject any frequency. They inject a DC pulse.
 

Hv&Lv

Senior Member
Location
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Occupation
Engineer/Technician
I kinda like the suggestion of the old welder...

now that would be interesting!!!
 

480sparky

Senior Member
Location
Iowegia
I can just imagine some sort of foreign material in the pipe causing the issue. You locate it, repair it..... then find out there's another issue elsewhere. When all is said and done, you've got a bunch of repairs done because the object skipped along the conductor like the iceberg Morse-coded the side of the Titanic.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
Have an issue with a pull of 225' 4/0 6 cables. One of my cables did not make it. What is the best tool/procedure to locate the short within the EMT?

LarryFine said:
At first, I thought the OP was saying that one conductor was too short for the pull.

When I keep reading it, it does sound like that might be what he is saying.

-Hal
 

Sierra Me

Member
Location
Nor Cal
Occupation
Multi licenced contractor
Love the synergy. Thank you for the responses.

Cost isn't the problem, down time is. I've ordered a TDR500 and will re-access the fix once the short is found.

Once again thank you.
 
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