Tone Generator Fun!

[EricVonHa]

Anything better to use than a tone generator to find an underground wire?

When my place was built, there was a direct burial wire 12/2 wire installed in the trench (generally) from the basement, across the driveway and near to the road. It should be near the sewer pipe that exits the property. This was intended for a future motorized gate, lamp post or whatever.

Gdamn if I can't find it in the ground now. Dug a 3' x 3' hole near the plumbing clean-out in the yard thinking that it's gotta be near there. Nope.

So, I hooked up a tone generator onto the wire where it exits the foundation in the basement. I get good tone on the 3' of wire in the basement. As another test, I'm using a 6' long drill bit as an "antenna". In the basement, if I get place this drill bit within a few inches of the wire, my inductive amp/speaker blares away with a warble tone saying "it's right here!"

Outside the foundation in the flowerbed only 2' away, I sank that drill bit probably 30 times. I can't locate the wire. Took measurements inside the basement, too, in order to make sure I'm in the vicinity while making swiss cheese outside. Bleh.

This is the unit that I'm using now. Mostly geared toward finding any kinda wiring in a bundle over long distances in an above ground format.

Tone Generator

Anyone have any experience toning underground wires? Thinking on buying this because lots of people say they've found invisible dog fence wires and so forth with this one:

More effective for underground wires?

 

[The Cobbler]

the tone generator you have is probably not meant for underground use, it's more for finding which run is which & that. they're not very powerful. ( at least mine isn't)

 

[Bert_]

I locate underground wires pretty often. I've got 2 locators, both are Progressive Electronics. Mine just have a tone and the newer one also has a signal meter. With a little practice it's not hard to locate a wire to within a few inches.

I'd say the one you linked used the same principal as mine but it's hard to say if it works very well. It looks like it straight off the boat from China.

 

[BukitCase]

Bert, went looking for Progressive - seems they've changed the name

https://www.ecmweb.com/construction...ressive-electronics-changes-name-to-tempomesa

Eric, this

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

is more likely what Bert has (or similar) - whole different "animal" than above-ground wire sniffers... Steve

 

[EricVonHa]

I locate underground wires pretty often. I've got 2 locators, both are Progressive Electronics. Mine just have a tone and the newer one also has a signal meter. With a little practice it's not hard to locate a wire to within a few inches.

I'd say the one you linked used the same principal as mine but it's hard to say if it works very well. It looks like it straight off the boat from China.

How far away from The Wire does the Progressive unit work? Are you doing any digging? Do you have a model number? Thanks!

 

[EricVonHa]

Bert, went looking for Progressive - seems they've changed the name

https://www.ecmweb.com/construction...ressive-electronics-changes-name-to-tempomesa

Eric, this

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

is more likely what Bert has (or similar) - whole different "animal" than above-ground wire sniffers... Steve

Interesting to note, the short range unit I'm trying to use came with GREENLEE storage case.

 

[Bert_]

How far away from The Wire does the Progressive unit work? Are you doing any digging? Do you have a model number? Thanks!

You won't get a signal if you're more than 10' or so away from the wire.

But that's ok. You either start at the beginning, where you know where the wire is, or you just start walking around in a zigzag until you get a signal.

I do the digging.

 

[Bert_]

Bert, went looking for Progressive - seems they've changed the name

https://www.ecmweb.com/construction...ressive-electronics-changes-name-to-tempomesa

Eric, this

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

is more likely what Bert has (or similar) - whole different "animal" than above-ground wire sniffers... Steve

Yea that looks exactly like the newer one I have.

Op, you might be better off just to hire someone too locate it. I would say the tempo (progressive) in the link is one of the more inexpensive locators out there but still way more than you're going to want to spend. If the $40 one works then that's great but I think it's taking a chance.

I think most electricians would have a locator.

 

[EricVonHa]

Yea that looks exactly like the newer one I have.

Op, you might be better off just to hire someone too locate it. I would say the tempo (progressive) in the link is one of the more inexpensive locators out there but still way more than you're going to want to spend. If the $40 one works then that's great but I think it's taking a chance.

I think most electricians would have a locator.

Yeap on electricians having a locator. I'll need to ask around I think.

The 2nd link I posted for a locator seems to work fairly decent for buried wienie wire for invisible dog fences, but I don't see that someone found a wire 5' in the ground.

I dug a monstrous hole already and that was no bueno. Digging rocks out of a bad fill mix was waaay too much work.

Need to work smarter, not harder. Need more technology tools!

 

[Miss the Pontiacs]

The Tempo unit is similar to the ones I have. Which I use mostly to identify data/voice cables. I don’t know about this unit but have found with the new materials in sheathing the wire, especially the Cat cabling, they aren’t that good even for that purpose. You pretty well have to be near the other end of the cut wire to locate an individual run.
I have no idea on the second unit used for invisible pet fences.
Short of hiring a locator have you tried a metal detector. Can’t see why that wouldn’t work as they can pick up a pop can pull if you are looking for pop can pulls.

 

[BukitCase]

I've never tried this, just read about it in a few places FWIW - disconnect the wire at both ends (if it isn't already), clip lead from the (bare) spark plug wire of a lawn mower to the "lost" wire (metal to metal, duh) - take a cheapo transistor radio, AM band, tune to a quiet area on the dial (good luck in some areas) - walk around like ya knew what you were doin' :=)

Downside - you'll look like an idiot, may not work at all :=)
Upside - quite a bit cheaper than EITHER previously mentioned ideas, and it's hard to find a noisier signal than a spark gap... Steve

 

[EricVonHa]

I've never tried this, just read about it in a few places FWIW - disconnect the wire at both ends (if it isn't already), clip lead from the (bare) spark plug wire of a lawn mower to the "lost" wire (metal to metal, duh) - take a cheapo transistor radio, AM band, tune to a quiet area on the dial (good luck in some areas) - walk around like ya knew what you were doin' :=)

Downside - you'll look like an idiot, may not work at all :=)
Upside - quite a bit cheaper than EITHER previously mentioned ideas, and it's hard to find a noisier signal than a spark gap... Steve

I kinda get what you're saying, Steve, but what is injecting the signal into the spark plug?

Calling electricians shortly. Know a couple. Someone has to have one these magical wire finder things on a truck somewhere

 

[BukitCase]

"what is injecting the signal into the spark plug?"

Sorry, forgot to mention; the lawn mower is RUNNING, magneto supplying the spark... Steve

 

[Innovate1]

You could build up something more suited to the task. I haven't tried this one but it looks promising:
https://makezine.com/projects/make-20/wirefinder-9000/

Years ago Circuit Cellar magazine had a build article on a more advanced one that I have always thought would be interesting to make but it was much more complex to build and information on it is hard to find.

 

[kaffine]

Check your local rental yards some of them carry underground cable locators. Need both the transmitter and receiver. They are just really beefed up tone sets but often can give you depth of cable as well. The antennas are much more directional than normal tone sets. If there are any other metal pipes or wires you want located should be ready to locate them might as well get as much use out of it if you are paying the rental fee.

https://www.sunbeltrentals.com/equipment/detail/1432/0110025/cable-locator/

Other options would be if you have a signal generator you could use it as it can put out a stronger signal than the one from the tone set. Or if you have a stereo with a good amp hook it up to the wire and play a tone around 1kHz and crank the volume up.

 

[EricVonHa]

Many thanks for the SunBelt referral!

I think I have a solution... will circle back with everyone to let you know what I find.

 

[EricVonHa]

Well, now we're at a stand-still and I would like to know if anyone has any experience with 220V single phase and blowing open/away from ground

The epiphany was that the un-used power wire runs near to the sewer line that exits the property. I talked to a smart electrician friend of a friend kinda fella and he said he'd feel kinda bad for taking my money after I essplained the situation to him. He said it's a waste of his time because the utility company will come out and scan the property and mark the power lines for FREE. Though, I have to put power on the line for the surveyor to find the line.

Unfortunately, in this quest, I discovered that there is a 50k ohm short to ground on the line. Does this surprise anyone? The line has been buried in the ground for over a decade and I doubt that it was suitably terminated or safed-off.

So, got out the trusty ole heavy gauge extension cord. Connected it an un-used breaker in the breaker panel. I energized that line 3 TIMES and it barely tickled the line for a split second before the breaker goes POP.

So, who wants to get adventurous with me and hook this baby up to straight 220v to blow it open!?

 

[Bert_]

They aren't supposed to locate private lines. If you sweet talk the guy doing the locate he might help you out though.

 

[nadogail]

I have seen mine detectors used to locate buried cables and pipes. Plastic pipes were found by feeding an electricians fish tape into them and locating the fish tape.

At the time I was employed by an electronics company making mine detectors for military use.

 

[EricVonHa]

Thanks guys, going to try opening the 50k ohm short on the cable by feeding some high-current 220v into the wire this weekend.

As it is, the high-resistance short effectively causes the wire to appear as a single conductor. Tone generators don't work on one conductor.. so, as you said, it requires a metal detector or do some more digging.. or open the wire by brute force current.

Still curious if anyone has been successful in opening a high-resistive short with high voltage/current in a direct burial situation? It won't take that long to hook up... just curious if I'm setting up a fail?

 

[Innovate1]

Sounds like a bad idea to me. Should be able to do a locate on the line without a problem - the power company does it by simply putting a small ground rod in and hooking the signal line to the case of the ground mounted transformer. Or you could disconnect the other lines so nothing is connected to ground and run the signal to all of them. Don't see why it can't be used to locate a single conductor but I haven't done it.

 

[MoonRise]

A 50k ohm 'short' on a 240V line will only flow 0.005 amps. Because that is the Law (Ohm's Law ).

That will typically not trip a breaker.

If you insta-tripped the breaker when you tried to energize the uncooperative buried line, I think you have other stuff (problems) going on.

And if the buried line is giving all these problems, you might just be better off abandoning it and running a new line to use.

Cause by the time you find all the problems in the buried line, you might have dug up all or most of it anyway. And if you don't dig it up to find and fix the problems, Mr. Murphy probably says that the sections you don't dig up will also be bad or fail shortly thereafter anyway.

 

[Innovate1]

I am guessing it measures 50k with low voltage applied for the measurement - something like 10 V or less. But with higher voltage it breaks down and flows as much as the source can produce. Once an arc starts it can carry a lot of current. That's why most breakers have a 10,000 A interrupt rating. That's the current it can interrupt without exploding. Although a typical residential branch circuit can only supply about 500 - 1000 A short circuit. That's the current that flows before the breaker opens in a short circuit condition. I do fault tests on equipment and have measured it.

 

[EricVonHa]

A 50k ohm 'short' on a 240V line will only flow 0.005 amps. Because that is the Law (Ohm's Law ).

That will typically not trip a breaker.

If you insta-tripped the breaker when you tried to energize the uncooperative buried line, I think you have other stuff (problems) going on.

And if the buried line is giving all these problems, you might just be better off abandoning it and running a new line to use.

Cause by the time you find all the problems in the buried line, you might have dug up all or most of it anyway. And if you don't dig it up to find and fix the problems, Mr. Murphy probably says that the sections you don't dig up will also be bad or fail shortly thereafter anyway.

I am guessing it measures 50k with low voltage applied for the measurement - something like 10 V or less. But with higher voltage it breaks down and flows as much as the source can produce. Once an arc starts it can carry a lot of current. That's why most breakers have a 10,000 A interrupt rating. That's the current it can interrupt without exploding. Although a typical residential branch circuit can only supply about 500 - 1000 A short circuit. That's the current that flows before the breaker opens in a short circuit condition. I do fault tests on equipment and have measured it.

The scenario is that the 12/2 wire is routed from the basement out through the foundation, under the driveway and dead-ends near the sewer plumbing clean-out. Essentially it is a 75' piece of wire with open ends.

My 50k ohm resistance measurement is consistent between all 3 conductor combinations.

If I attempt to only attach a "hot" 120vac line to any conductor, ****, the breaker snaps off immediately.

My thought is that the dead-ended wire out in the yard near the clean-out is not protected or safed-off in any way. The end of the wire is probably laying in the dirt and is effectively "grounded" to the earth by default. This makes sense because who puts wire nuts or buries a junction box without any future access? I sure didn't do it!

I'll try the 220v sizzle this weekend. Yes, it is a low current measurement when V=IR. However, the 200 AMP service and 20 amp breaker say that there is nearly an unlimited supply (not really) of current being unleashed right to ground, so the breaker pops right away.

===

On another note, the last time I had a utility done search on the property, I remember that the tracer dude did place an inductive something or other around the owner-side of the meter power feed.

I *might get lucky *if their system can detect a signal on a 50k ohm grounded neutral. Somehow I doubt it, however, their equipment is big $$ and super sophisticated. It'll be a challenge for sure.

Thanks for your brainstorming ideas!

 

[Bert_]

A live wire in the dirt will absolutely NOT trip a breaker. It might flow a few amps at best. Something else is going on.

 

[walta]

I am guessing the breaker is a GFI/ ARC fault breaker.

Walt

 

[EricVonHa]

Nailed it, yes, there is GFI on the ckt.

In further testing, I hooked up a cord directly to a non-GFI breaker to shoot power through the buried wire. Still cannot find the wire out in the yard.

==

The utility search company came out and did the survey and marked their lines between the meter and pole/transformer.

They are using a "RadioDetection RD8000" for their underground searches.

The guy that visited was literally old and old school. Nice guy, but did not know technology. I mentioned to him that the guy that visited months ago also tagged the cable lines in the area of excavation.

He said, "nope, can't do it, if I change any settings on this, I wouldn't know how to change them back!". Believable. Other conversation indicated he was not up on technology at all.. so, couldn't ask any further.

Long story short, we can close this thread. We'll hand dig from the house to the motorized gate locations and install a new direct burial 120vac line in PVC. There's a couple teenagers on tap who will gladly work for a few pesos and pizza. Work smarter, not harder is what they say I'm not sure which end of the equation I'm on, this project should be done by now!

 

[EricVonHa]

If anyone is interested, here is a video on the RD8000 capabilities.

Super high-tech.. indicates direction left/right AND can do it by indicating current flow. This is helpful if there are multiple cables in a similar location.

It can also identify fault locations underground. Impressive!

 

[Speleo]

Divining Rods, made from brazing rods will work just fine. Old School telephone guys always carry them for backup.
Speleo