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#15848 - 10/30/02 06:44 PM underground sevice problems
bayala13 Offline
Junior Member
Registered: 12/15/01
Posts: 2
Loc: ia
About a year ago I buried some aluminum 2-2-2 rated for underground sevice. It is about 100 ft to the shop from the service source which is the breaker in the house box. I buried at 18" and have had no problems until about a day ago when I notice it dropped one of the hots and I only had 110v in the shop. I double and triple checked all breakers and connections. I found that one of the hot wires somewere underground is no longer conducting. I also eliminated the possibility of a bad breaker by switching the two hots and rechecking with a volt meter. That same wire stays dead no matter what I switch around or do. What is strange though is the fact that on the good wire out in the shop it reads 120v and the "bad" one reads anywere from 50v to 100v but as soon as I put any load to it, it drops to 0v. I dont understand where the 50v-100v is comming from. Has the voltage went to ground? why hasn't the breaker thrown itself? And also how do I find the bad spot? is there any tricks? I tryed to be real careful when I filled the dirt back in and used my bare hands for the begining of the fill in so I would not cut the wires with the shovel. Any help would be appreciated. I am not looking forward to redoing this job. Any ideas on fixing this would be welcomed. Thanks
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#15849 - 10/30/02 07:06 PM Re: underground sevice problems
edmat Offline
Junior Member
Registered: 10/30/02
Posts: 3
Loc: Hot Springs, AR
Are you a electrican? If you do not know what is going on in the situation you out line in your question then you should seek a electrical contractor before you get killed.
#15850 - 10/30/02 08:19 PM Re: underground sevice problems
arseegee Offline
Registered: 01/28/02
Posts: 324
Loc: Statesboro, GA USA
All you can do is trace the break. You may be able to find an electrician in you area that has an undergroud circuit tracer. It may keep you from having to re-trench the whole feeder.

And yes you can have a broken wire and the breaker will still hold due to a lack of resistance to ground or lack of proper grounding.
#15851 - 10/30/02 09:47 PM Re: underground sevice problems
Trumpy Offline

Registered: 07/05/02
Posts: 8211
Loc: SI,New Zealand
Maybe your local Power company can help, they should have a cable fault locator unit.
Let's face it, these days if you're not young, you're old - Red Green grin
#15852 - 10/31/02 02:53 AM Re: underground sevice problems
sparky Offline
Registered: 10/18/00
Posts: 5303
just say no to direct burial.....
#15853 - 10/31/02 04:37 AM Re: underground sevice problems
Redsy Offline
Registered: 03/28/01
Posts: 2056
Loc: Bucks County PA
Direct buried cables are required to be 24".
#15854 - 10/31/02 04:45 AM Re: underground sevice problems
electrician02125 Offline
Registered: 02/01/01
Posts: 89
Call an electrician before someone gets killed and or something gets destroyed.

Just my opinion.

Aluminum wire sucks by the way.
#15855 - 10/31/02 02:13 PM Re: underground sevice problems
Tom Offline
Registered: 01/01/01
Posts: 1044
Loc: Shinnston, WV USA
Wait 'till the first snowfall then look for the green spot. I've found many bad tornado magnet feeders this way.

Few things are harder to put up with than the annoyance of a good example.
#15856 - 10/31/02 03:32 PM Re: underground sevice problems
George Offline
Registered: 02/23/02
Posts: 375
Regardless of where the break is underground, you will need to replace the whole wire.

Turn the power off, start digging and this time use conduit.
#15857 - 10/31/02 04:03 PM Re: underground sevice problems
sparky66wv Offline
Registered: 11/17/00
Posts: 2232
Loc: West Virginia
Tom, LOL Heh heh... "tornado magnet"... too funny!

Good point, George.

bayala13, Pipe it (but over-size the pipe for an easier pull, i.e. 2" for 100A, or 3" for 200A). It'll be more resilient and if it does fail, it'll be easier to replace (ideally).
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