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Posted By: Rewire buried cable short - 01/28/10 02:45 AM
I have been getting several calls from people with shorted UF cable. I am looking to purchase a good tracer and would like some input. Amprobe has several models from low to high price. What I need is the ability to locate the location of a short in buried UF 18-24 in deep so I dont need to dig up the entire yard.
Posted By: A-Line Re: buried cable short - 01/28/10 03:35 AM
I used this....

Amprobe AT-2005

[Linked Image from i95.photobucket.com]


to find this short circuit in an underground feed ....

[Linked Image from i95.photobucket.com]


located here. The breaker would trip when the ground was saturated with water.

[Linked Image from i95.photobucket.com]

[Linked Image from i95.photobucket.com]



I traced the wire from both ends to make sure of the location before I dug it up. The landscaper who installed it claimed there weren't any splices in the cable. As you can see it wasn't buried to the proper depth either.





Posted By: HotLine1 Re: buried cable short - 01/28/10 03:41 AM
All I can dd is "ditto", but no pics for proof.

Posted By: Rewire Re: buried cable short - 01/28/10 04:17 AM
I see that Amprobe has several models of the AT series 2001,2002,2003,2004,2005. do you need all the bells and whistles or does the AT 2001 have what you need?
Posted By: HotLine1 Re: buried cable short - 01/28/10 03:12 PM
I went for the bells & whistles. BTW the 'factory' reps for any support issues you may have were really great!

You may want to send a PM or email to 'Webmaster' (Bill Addis) for his input!
Posted By: A-Line Re: buried cable short - 01/28/10 04:37 PM
Originally Posted by Rewire
I see that Amprobe has several models of the AT series 2001,2002,2003,2004,2005. do you need all the bells and whistles or does the AT 2001 have what you need?

I went with all the bells and whistles.
I bought the AT-2005 model and have no regrets.
Usually I only have regrets when I try to be cheap and end up wishing I had spent more.

I use this tool a lot and have found numerous hidden splices behind sheetrock.
Other contractors have told the homeowner that they would have to start tearing out sheetrock until they locate the problem.

Charge a flat fee for locating the problem and include enough in the fee to pay off the tool in the amount of time you feel comfortable with. If you charge enough, your customer's are paying for the tool not you. After all you're saving them a lot of money by not digging up their yard or tearing out a bunch of sheetrock.

Once the problem is found you can then give them a price for the repair.
In the case of the cable I show in the picture my price was for installing a new line in conduit buried to the correct depth.

The landscaper and the homeowner weren't too happy when I told them the freshly landscaped yard would need to be dug up for this to be done properly.



Posted By: renosteinke Re: buried cable short - 01/28/10 06:43 PM
A-Line, this is truly a case where a picture is worth thousands of words.

At $1000, it's far from cheap. Yet, I've had to try to run down the exact type of fault you describe a number of times, using everything from a dowsing rod to a minesweeper, without a great deal of success. One of the major problems has been false paths - getting a strong tone where there are no wires.

This also seems an ideal candidate for tool rental companoes to offer .... does anyone have that option where they live?

Posted By: A-Line Re: buried cable short - 01/28/10 10:20 PM
Below is a photo of a hidden j-box I located using the AT-2005.

A basement bedroom had some of the receptacles showing an open neutral. Another electrician had been out and looked at it and told the homeowner he would have to tear out sheetrock until he found the problem.

I traced the circuit through the bedroom, then through another bedroom, down a hallway and into the family room where I cut a hole in the ceiling and found the hidden box.

[Linked Image from i95.photobucket.com]

On another call at a different residence the front porch light and front entryway lights weren't working. This was an old house and had been remodeled a few times.

I traced the circuit down the hallway, through the kitchen, through the family room, down the family room wall and into an old cellar below the family room.

I found an old pushbutton switch down there and when I turned it on everything worked again. Someone had turned the old switch off. It didn't go to anything but the lights that weren't working. Not sure why it was there. Someone must have pulled power from whatever the old switch went to to feed power to the lights for the remodeled porch and entryway.

The homeowner kept asking me what I was doing in the kitchen and family room when the problem was at the front of the home. I got the feeling he felt that I didn't know what I was doing.


Posted By: Rewire Re: buried cable short - 01/29/10 12:25 AM
I think I will make the investment in the AT 2005 this is the type of thing we run into alot.It should pay for itself quickly.
Posted By: renosteinke Re: buried cable short - 01/29/10 12:25 AM
That is a superb picture of a concealed J-box. When you made that hole and found the problem - on the first try - I'm sure the customer's opinion of you changed dramatically.

I frequent a DIY forum where it is common to hear someone insist they can hide the j-box 'just this once,' and not to worry, no one will ever need to get to it.

I would probably have been able to follow the circuit with my $100 toner; most certainly, the $250 toner would have found it. They're not up to finding the damaged UF, though.
Posted By: CDS Re: buried cable short - 01/29/10 01:04 AM
I noticed the 2001 is for up to 300 volts , the 2005 is good to 600 volts
The 2005 will find opens with power off .
Anyone see more difference than that .
I'd love to have one of these , but I can more afford the 2001 .
For residential , can anyone see the need to get the 2005 over the 2001 ?
Posted By: Obsaleet Re: buried cable short - 01/29/10 05:01 AM
I have the 2001. Ithas worked well most of the time. I have experiances the stray signal Reno spoke of many times. Noise also is a problem. I have had some older commercial building that the grounding was not so good and there is a ton of noise almost cannot hear the tone. I have not had good luck with dealing with Amprobe, as none of the local parts dealer carries them any longer, it has been troublesome to get leads that are damaged. The 2001 kit I purchased did not come with a tone generator. I had to buy that separate. It is a great asset. It is a great product, just not thrilled with Amprobe at this point.
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