using a metal detector to find power line?

I need to locate a buried electric wire going from my house to barn. Only about a foot deep and I have the end uncovered to follow it. I can turn the power off or on, whichever works better. I have a general purpose metal detector that I borrowed from a neighbor who hasn't used it much himself.

That's the good news, bad news is the thing seems to beep at random and never particularly when it is over the electrical wire. Will it detect the plastic clad wire? Should the power be off or own for best results? I seem to have a bad spot in the wire but don't want to have to dig up over 120 feet of wire to find the bad spot.

Thanks for any help or suggestions where to find help!

Hu
 
Most "general purpose" metal detectors will only go down 2 to 3 inches into soil Hu. You might stop in Home Depot or Lowes and see if they have something that will penetrate deeper like what a gas line company uses to find pipe perhaps?
 
One of the minor handicaps of living in the boonies, my nearest lowes is thirty miles one way, nearest home depot forty in the opposite direction or sixty in the same direction! I tried my "local" rent all place fifteen miles away, they don't rent any metal detectors.

I have watched the pro's finding lines and they use an entirely different type of detector, no idea how accurate it is but they seem to make it work using it every day, no doubt a part of it.

The Amazon link isn't working for me but the long version of a short story is it looks like I start digging on over a hundred and twenty feet of line until I find the bad spot. It isn't in conduit and I have to go easy so I don't have many more bad spots!

Ah well, back to the shovel.

Hu
 
That's the good news, bad news is the thing seems to beep at random and never particularly when it is over the electrical wire.

Sounds like you might as well as give dowsing a try!

You'll probably want copper for electrical lines. :rolleyes:
 
I wouldn't dig up the whole thing. Just dig test holes at quarter distance locations until you find the line. Then turn on the power and use one of those cheap beeping current detectors to narrow down the section the break is in...dig at the mid point of that section and test there, and so on until you only have to dig up a ten foot section. If you have driven over the line lately, maybe look there first:)
 
more to the story!

I wouldn't dig up the whole thing. Just dig test holes at quarter distance locations until you find the line. Then turn on the power and use one of those cheap beeping current detectors to narrow down the section the break is in...dig at the mid point of that section and test there, and so on until you only have to dig up a ten foot section. If you have driven over the line lately, maybe look there first:)



Well,

This is gonna get kind of painful but there is more to the story, much more! A sophisticated sniffer might find the issue but nothing I have.

The line curves across an old barn lot from the house to the barn, an old dairy barn. The line is on paired sixty amp breakers at the house, and should carry about fifty amps the distance it is running over the I believe eight gauge wire. Now things start to get interesting. The wire that comes out the ground at the other end is a different type of wire than goes into the ground at the house. No conduit once it is out of sight underground so there is a splice somewhere along the way, almost certainly done by the owner, deceased in the nineties.

I have 122 volts per leg at the barn, spot on. I don't have any amperage. I can run one of the tiny air compressors with maybe a tenth horse motor or less, a third horse motor doesn't even twitch out of the same receptacle that the small air compressor runs off of. The power in the whole barn is like that including when I ran a new four foot pigtail and twenty amp receptacle on a new breaker from the barn box.

I don't blow the breakers anywhere and the meter at the house isn't spinning ninety miles an hour which I have seen when there was an electrical leak long ago somewhere else. Another story but yes I have seen an underground electrical leak before. My guess is that there is major corrosion wherever the underground splice is in the present situation. Find the splice and I think I find my headache.

Without knowing where the cable runs my only options are to dig it up all the way or to dig trenches to find the cable dividing it into a half and then quarters as you suggest. Compounding this is that there is a lot of clay and gravel in this land plus this has been a homesite since probably before the war of northern aggression, no telling what else may be in this ground. I started my trenching from the end near the barn where I hoped the splice was near. Knowing what I have already found around this place I worked my way down the conduit and out to the bare wire. Now I can gently uncover it as I go. Trying to force a shovel through all of the stuff in this ground to cut right angle trenches I am almost certain to damage the unprotected cable with the trenches to divide the cable into sections.

I never seem to tangle with simple projects with easy solutions!

Hu

PS: Brent, I kinda like the dowsing idea! Probably just find oil, there is a bunch under here, not mine though!
 
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Most states/counties have a free "Call before you dig" service that could locate and mark your lines for you. Here in NE Ohio, they'll locate and mark all underground lines - water, sewer, electric, gas, etc. anywhere on your property. Should be worth a call, at least.
 
Sounds like a ton of work Hu. If it wasn't too expensive I'd rent a trencher and run new wire. At least you'd know it was done right and you wouldn't have problems again. If your wire isn't in conduit then it could be close to breaking in several spots from rubbing on the gravel in the ground. It would suck to find the bad spot and have another one happen a few months later.
 
+1 on before you dig. If it were me I would abandon the old, incorrectly installed, wire and do right. Searching for a bad spot you run the risk of cutting the wire again creating yet another opportunity for future failure. In the end you will feel better knowing it's been done correctly and have peace of mind.
 
Jim,

"Dottie" only checks for their own lines in my state. I'm sitting on a hundred acre farm and this is a privately ran line. I have the electric company coming out to check a badly weathered service pole. I don't know if he will have one of their metal detectors on the truck since there are often guys that only check for wiring driving more fuel efficient vehicles. If he has the device I'll probably "buy the beer this evening" in trade for checking the line. They have actually gotten pretty well worthless in my state as they simply mark the driveway and put arrows, either they have lines running across the front of the property or they don't. Not much help actually knowing where the lines are or how deep. I still call dottie because it covers my rear concerning legal action. When they jerked me around on a half mile of new interstate fiber optic on a piece of property for three months years ago I called them one morning and told them I had a D-8 Cat coming in that day and I would find the line one way or another! Amazing how cooperative they got.

Bob,

Just been told my SI joint is in bad shape on one side to go along with my other assorted ailments and blood pressure is in triple digits top and bottom. However, the new line would run a thousand dollars or close to it including trencher and all. I'm concerned there may be other hot lines in the area of some of the digging and it definitely runs under a cyclone fence and crosses the water supply to the house, probably over it but that is only a guess too. I do know that water supply is the thin roll tubing that fails over time and is very old. I had a section of it that I replaced that was just porous, a zillion tiny holes.

The heat is on to move my lathe to the barn but I don't own this property. I'm between a rock and a hard place because the owners don't need electric at the barn, I do if I want to keep turning. I'm pretty heavily invested in turning at this point and need to keep on. Much more to the story but this will do for starters! ;)

Hu
 
I'd try making 2 pieces of clothes hanger in to L shaped pieces. Then holding the short ends loosely in your hands with the long ends strait out in front of you walk back an forth across the area where you think the wire is & when the wires pull toward each other & cross there is your wire. I watched an electrician do this & tried it my self really weird sensation. I went on to find other things like metal pipe etc.
 
I'd try making 2 pieces of clothes hanger in to L shaped pieces. Then holding the short ends loosely in your hands with the long ends strait out in front of you walk back an forth across the area where you think the wire is & when the wires pull toward each other & cross there is your wire. I watched an electrician do this & tried it my self really weird sensation. I went on to find other things like metal pipe etc.



I have seen too many odd things to dismiss dowsing. I will do it when I'm not expecting company though! I used to know an old farmer that genuinely believed in witchcraft and quite a few things most young people didn't. He might not be right about why something worked but if he said it worked you could take it to the bank! He is gone along with pretty much all of that generation. I wanted to make sure the knowledge he and some other old people I knew wasn't lost but that was twenty-five years ago. I moved out of the area and by the time I came back it was too late.

We gain new knowledge all of the time but we lose a lot too. Funniest thing in the world, they taught people at the state university all the way to an undergraduate degree in agriculture but then if they wanted a PhD, they came to the lab farm where Red, a man that could barely read and write, taught them how to farm!

Hu
 
Hu,
Don't know about where you are, but when I put my shop up, needed to run wire underground to it, only about 75 to 100 feet, but I was able to rent a ditch witch from the local equipment rental store for about $100 for the day.... I cut a trench about 6" wide and about 18" deep all the way from the power pole at the corner of the house where the main connection was to the shop... the electrician then ran gray tubing/conduit for the electrical wire and wire through to the shop... don't remember the cost of the wire, but wasn't all that much.... all told with the ditch witch, electrician and the wire, I spent just a little over $500. That was 9 years ago though.

Instead of trying to find the existing wire, might me more cost effective and efficient to just run a new wire.
 
Rent a trencher and put in a new line. My son-in-law lost power to his shop and we started digging up the line...found and fixed three previous splices and it still didn't work, so we gave up. He just laid a new line on top of the ground for immmediate power and a few days later rented a trencher and put it under ground. Doing that took much less time than we had spent digging and looking for breaks.
 
I'd try making 2 pieces of clothes hanger in to L shaped pieces. Then holding the short ends loosely in your hands with the long ends strait out in front of you walk back an forth across the area where you think the wire is & when the wires pull toward each other & cross there is your wire. I watched an electrician do this & tried it my self really weird sensation. I went on to find other things like metal pipe etc.

I've done this to find a buried electrical line that was about 4' underground. I was skeptical, but it worked like a charm!
 
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