Help finding a broken wire.

[Wyoming09]

Not wanting to hijack another thread about Electrical receiver / transmitter tool to identify wires I need advice. I have a light near the street controlled by a switch at the back door. Somewhere between the switch and lamp the wire is broken. The wire, I believe, is buried along the driveway. I need a way to locate the break. What tool do I need to help locate the break without digging up all approx. 75 feet of wire. Does such a thing even exist? Any help would be greatly appreciated. Thanks, Marty

 

[rhandwor]

Usually something had to cut the wire look for a hole in the ground. Have you used a meter and made sure the switch is working. You could also have a bad connection at the lamp. Is your fuse or breaker tripped? You may have to run a new wire all the way.

 

[tonyciambrone]

Depends on how you feel about electrical code but I doubt there is a junction box between the light and switch where you could repair the wiring...I think you would be best off eliminating incoming power, the switch and light fixture as possible faults and then pull new wire.

 

[Bert_]

It's not a tool your average joe is going to have but an undergound fault finder is what you need.

I've got a "pulser" made by progressive electronics. It's 20-30 years old but works well. It will get you within inches of the fault. You then dig it up and fix it with a direct buy spice.

 

[kctyphoon]

Is it direct buried, or in a conduit? If it's in conduit, the wire shouldn't just "break" but who knows.., just pull a new wire in as you pull the old out..

If it's direct buried, buy a flashlight.. it'll be easier

 

[Wyoming09]

Thanks for the help guys. I've got some time before the ground thaws but it looks like I may just have to hand dig the entire length until I find the break.

 

[Slednut]

It's not a tool your average joe is going to have but an undergound fault finder is what you need.

I've got a "pulser" made by progressive electronics. It's 20-30 years old but works well. It will get you within inches of the fault. You then dig it up and fix it with a direct buy spice.

This is what I use to find faults, goes down to 19 gauge. If you know someone who has access to a fault locator they are really easy to run.

Even with it set up at 19 gauge it would still find the open with good accuracy.

If the wire is aluminum I would replace it.

 

[kctyphoon]

This might be a stupid question, but how SURE are you that the wire in the ground is broken, and it's not a connection on either end that's your issue?

Anyway, on a more serious note- and don't quote me on this, cause this really isn't my field, BUT - I'd think what you need is a cable fault finder. Like this one -https://www.ebay.com/p/Harris-TS-100-Cable-Fault-Finder-Harris-Ts100/1224593394?iid=183052851093
I wanna say you'd be able to put the meter on one side, and it should be able to tell you how many feet away from where you are that the break, or open, is.. I'm SURE there's a YouTube video that can show you how to do this..

 

[Snakebyt]

Thanks for the help guys. I've got some time before the ground thaws but it looks like I may just have to hand dig the entire length until I find the break.

If you are going to go that far, why not go ahead and lay conduit and new line while its already dug up?

 

[Fierljeppen]

I have a light near the street controlled by a switch at the back door. Somewhere between the switch and lamp the wire is broken. The wire, I believe, is buried along the driveway. I need a way to locate the break. What tool do I need to help locate the break without digging up all approx. 75 feet of wire. Does such a thing even exist? Any help would be greatly appreciated. Thanks, Marty

Ideal 61-955 SureTrace Circuit Tracer Kit

This has become one of my favorite electrical tools. It's quite pricey, unless you're going to use it often and can write off tools, but it works! You-tube has some really good videos if you're interested. Ebay might save you some coin.

Good luck!

 

[rharman]

I'm going to second the thoughts of check the switch and, possibly, check continuity.
Be sure power is off.

 

[skruft]

Right - it is much more likely for there to be a problem at one end or the other, rather than a break in the ground, unless some sort of digging was done and cut the wire. Even switches break. I suggest, turn the power off and check continuity of the wire and everything at each end.

 

[Wyoming09]

A couple of years ago after a particularly wet spring when I would flip the switch the breaker would trip. After it dried up some then nothing. I believe the wire runs along the driveway and under a walk to the front porch. I'm thinking the wire was broken by the plow company putting in driveway markers before winter started. I'm pretty certain it's direct buried, seems like 6" to 8" deep. Part of the problem is that I have no idea where the wire exits the house. I'll be checking the switch and lamp socket this weekend. The weather seems to easing up a bit.

 

[Kaizen]

Thanks for the help guys. I've got some time before the ground thaws but it looks like I may just have to hand dig the entire length until I find the break.

Others have said it but not told you how to do it so here it is. At the switch disconnect incoming wires completely. Check you have voltage on those incoming then cap them. Go out to the light and connect the white and black TEMPORARILY. Go back inside with a tester that checks conductivity. Normally on a tester it’s the setting that makes a beep when both leads are touched. If you get a beep then neither are broken and it is in fact the light or switch. Also if it’s a light post with an outlet your problem could be there as well. If no beep you should dig the whole thing and replace as you should not splice underground. Spend the time testing as that is normally the place of fault


Sent from my iPhone using Tapatalk

 

[SteveW1000]

Lots of the cable detector look like they are for shallow depth so might struggle with finding this cable. Over here most utilities are buried so the crews use something like this to find services and prevent damage before digging. https://www.hss.com/hire/p/cable-and-pipe-locator-cat-3-hire-pack-1 Would think something similar should be available over there if so you might even be able to get someone to find the break for a six pack, If you can find it and dont want to replace the whole cable you can get epoxy filled splices to repair the break.

 

[NUTTSGT]

If it was a wet spring, what kind of light was it ? Did it get water inside it ? I'd be double checking everything before I started digging, including replacing the bulb with "another" new one. I thought I had an issue one time, turns out the new bulb that replaced the bad bulb was bad.

 

[shawhite]

Disconnect power. Short black and white at the load like said above. Disconnect switch and test for resistance across black and white. You should see low resistance. If not go back to the load and short black to ground (assuming a ground is in the cable). Go back to switch end gear for short. If no short is present this wire is probably open. Do the same with the white wire. After you are no isolating which wire has the fault then you can move to capacitance testing to try to isolate the fault. Usually you would check capacitance at both ends black/white, white to ground and black to ground. Once you have these values look up approx capacitance for 1 ft of same size cable used and do some math. This is not an exact science but has worked for phone men for many many years before the advent of fault locators and tdrs

 

[wyliesdiesels]

What you need is a cable locator but they arent cheap

https://www.amazon.com/dp/B001GHZP24/?tag=atomicindus08-20

 

[rlitman]

What you need is a cable locator but they arent cheap

https://www.amazon.com/dp/B001GHZP24/?tag=atomicindus08-20

A cable locator is one way. That will lead you directly to the underground fault, even if you do not know where the cable is.

If you know the cable's path, a TDR can tell you how far away the fault is. That may be enough to get you sufficiently close.

 

[mm08822]

Disconnect power. Short black and white at the load like said above. Disconnect switch and test for resistance across black and white. You should see low resistance. If not go back to the load and short black to ground (assuming a ground is in the cable). Go back to switch end gear for short. If no short is present this wire is probably open. Do the same with the white wire. After you are no isolating which wire has the fault then you can move to capacitance testing to try to isolate the fault. Usually you would check capacitance at both ends black/white, white to ground and black to ground. Once you have these values look up approx capacitance for 1 ft of same size cable used and do some math. This is not an exact science but has worked for phone men for many many years before the advent of fault locators and tdrs

A step is being missed.

Remove the bulb and disconnect from switch/ground and then test:
continuity between h-n, h-g, n-g.
Each of these readings should be open = infinity. Any of these tests fail then your cable is bad.

Then proceed looking for continuity between pairs of twisted conductors as stated.

 

[shawhite]

A step is being missed.

Remove the bulb and disconnect from switch/ground and then test:
continuity between h-n, h-g, n-g.
Each of these readings should be open = infinity. Any of these tests fail then your cable is bad.

Then proceed looking for continuity between pairs of twisted conductors as stated.

Good catch got a little a head of my self

 

[zmaxmotorsports]

Cordless/solar powered lights would solve the problem.

 

[ard]

Remember this thread when people say "direct burial- why bother with conduit"

 

[like2wheel]

Remember this thread when people say "direct burial- why bother with conduit"

Or. you could bury the cable to code and it would be deeper than 6-8 inches...

 

[zmaxmotorsports]

Or. you could bury the cable to code and it would be deeper than 6-8 inches...

Yeah but you still have to deal with moles and other nasty things in some places.