# Buried cable fault locator tool?



## RomexJockey (Apr 8, 2008)

Hi guys (and girls?)...I'm an electrical contractor in Vancouver, WA doing primarily residential service work. 

I'm starting to get into commercial service work a little more lately, and one of my customers has a problem with a buried cable running from one carport to another in an apartment complex. When the breaker is turned on, there is power at the first carport, but not the second, and then a few minutes later the breaker trips.

This seems to be a problem with the insulation on the buried cable (I'm assuming it's a direct burial cable, not in conduit) leaking just enough current to trip the breaker.

The solution would seem to be to locate the partial break or damaged insulation. My question is, what's the best tool for this job?

I know there are various toner-type tools made for locating cables that MAY work, but what about a cable that isn't actually broken? I need to locate the cable AND the bad spot. I've been looking at the Dynatel 573 *http://tinyurl.com/45c4u9*
...does anyone have any experience with this same situation or the Dynatel?

Thanks in advance....:icon_cheesygrin:


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## randomkiller (Sep 28, 2007)

RomexJockey said:


> Hi guys (and girls?)...I'm an electrical contractor in Vancouver, WA doing primarily residential service work.
> 
> I'm starting to get into commercial service work a little more lately, and one of my customers has a problem with a buried cable running from one carport to another in an apartment complex. When the breaker is turned on, there is power at the first carport, but not the second, and then a few minutes later the breaker trips.
> 
> ...


 
We have a few different ones in the shop, Greenlee-Tempo brands Tracker II is the best for the bucks I believe. There was a thread on this a while ago that might help but, I couldn't find it in search.


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## 480sparky (Sep 20, 2007)

I have both a Progressive (now Tempo) 2003 fault locater and a Rycom 6679 cable & pipe locater. Both have served me well.

http://www.tempo-textron.com/prod_detail.cfm?cat=800&subcat=802&pid=10412

http://www.rycominstruments.com/3-8879-Cable-Utility-Locator.asp


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## RomexJockey (Apr 8, 2008)

Thanks for the suggestions, guys.


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## Wireless (Jan 22, 2007)

What would work best under concrete?


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## 480sparky (Sep 20, 2007)

Wireless said:


> What would work best under concrete?


I know the Progressive works through 'crete.


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## kbsparky (Sep 20, 2007)

480sparky said:


> I know the Progressive works through 'crete.


You have to use sponges for that to work? :whistling2:

Has anyone ever tried to locate a fault in under-floor-tile heating elements with one? :blink:


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## ce2two (Oct 4, 2008)

Ever hear of a time domain reflectometer (T.D.R), used for copper , use a O.T.D.R. optical time domain reflectometer for fiber optic breaks ,opens:thumbup: use these two on a weekly basis...xnlt...devices


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## 480sparky (Sep 20, 2007)

kbsparky said:


> You have to use sponges for that to work? :whistling2:


Yepper!



kbsparky said:


> Has anyone ever tried to locate a fault in under-floor-tile heating elements with one? :blink:


Never had the need to try. Would be an interesting experiment.


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## gilbequick (Oct 6, 2007)

RomexJockey, have you tried meggering out the wires yet?


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## Faultfinder1 (Apr 21, 2009)

If you know that the insulation is broken I would recommend Timco Instrument's Spitfire, and if you simply wet the concrete it will pinpoint your cable fault. These are so much cheaper and easier to use than most other "high tech" gadgets on the market, and they do the same thing!
You might also be able to use a cable tracer and look for a signal loss at a certain point. You'd have to get a tracer with adjustable sensitivity though, or else it will just keep on tracing past the bad point.
Hope this helps!

www.faultlocating.com


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## drsparky (Nov 13, 2008)

ce2two said:


> Ever hear of a time domain reflectometer (T.D.R), used for copper , use a O.T.D.R. optical time domain reflectometer for fiber optic breaks ,opens:thumbup: use these two on a weekly basis...xnlt...devices


I use a Oscope when a TDR is not available. Not as convenient but it will work in a pinch.


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