Home Repair (alt.home.repair) For all homeowners and DIYers with many experienced tradesmen. Solve your toughest home fix-it problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 8,803
Default Homebrew underground wire break locator.

My father has a underground wire to a panel in his garage from his house. One
lead of the 220V service has apparently "opened" somewhere underground. It is
probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We suspect
that a splice was made in the wire someplace that may have failed.

Can anyone offer any good ideas for a way to locate the break without digging
the whole thing up? Maybe something using a transister radio as a locator and a
relay buzzer or something as a signal source.

Bob


  #2   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 1,743
Default Homebrew underground wire break locator.

Bob F wrote:
My father has a underground wire to a panel in his garage from his
house. One lead of the 220V service has apparently "opened" somewhere
underground. It is probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We
suspect that a splice was made in the wire someplace that may have
failed.
Can anyone offer any good ideas for a way to locate the break without
digging the whole thing up? Maybe something using a transister radio
as a locator and a relay buzzer or something as a signal source.


There are cheap voltage proximity detectors (I've got one about the size of
a pen); they cost about $10.

You can do a binary sort. Dig down to the cable at the 50' point. Any
voltage? If not, the break is between the 50' mark and the source. Move
toward the source to the 25' mark and dig down to the cable again.

Rinse. Lather. Repeat.


  #3   Report Post  
Posted to alt.home.repair
dpb dpb is offline
external usenet poster
 
Posts: 12,595
Default Homebrew underground wire break locator.

Bob F wrote:
My father has a underground wire to a panel in his garage from his house. One
lead of the 220V service has apparently "opened" somewhere underground. It is
probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We suspect
that a splice was made in the wire someplace that may have failed.

Can anyone offer any good ideas for a way to locate the break without digging
the whole thing up? Maybe something using a transister radio as a locator and a
relay buzzer or something as a signal source.


Probably most reliable is to rent a cable detector from the local rental
place. I'm fortunate a friend who used to do sprinkler systems has one
I can borrow on occasion. I suspect ones like his aren't that expensive
if it's something you might use more than once, but I really don't know.

It was reasonably successful in isolating a break in the feeder to one
of the waterers in the corrals last year -- we got within a couple of
feet at 3-ft depth on the one end. I was never able to find the other
end, though, even starting from that known point. In this case, it was
Al cable and the sheath had failed. Being in the feedlot, even though
that deep, it had been failed long enough a couple of feet had been
dissolved entirely by the strong urea solution in the water, even at
that depth.

But, it did find the starting point which saved quite a bit of time...

--
  #4   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 674
Default Homebrew underground wire break locator.


"HeyBub" wrote in message
...
Bob F wrote:
My father has a underground wire to a panel in his garage from his
house. One lead of the 220V service has apparently "opened" somewhere
underground. It is probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We
suspect that a splice was made in the wire someplace that may have
failed.
Can anyone offer any good ideas for a way to locate the break without
digging the whole thing up? Maybe something using a transister radio
as a locator and a relay buzzer or something as a signal source.


There are cheap voltage proximity detectors (I've got one about the size
of a pen); they cost about $10.

You can do a binary sort. Dig down to the cable at the 50' point. Any
voltage? If not, the break is between the 50' mark and the source. Move
toward the source to the 25' mark and dig down to the cable again.

Rinse. Lather. Repeat.

A good idea but may not work if the break is only in the neutral wire. It
might be possible to locate a neutral break by temporarily reversing the
wires so the neutral is hot.

Don Young


  #5   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 664
Default Homebrew underground wire break locator.

In article ,
"Bob F" wrote:

We suspect that a splice was made in the wire
Can anyone offer any good ideas for a way to locate the break


If the open is "clean", that is, NOT grounded or crossed, you can determine
the distance-to-open from either direction and use that information to
determine where to dig. Of course, such testing generally requires the use of
a TDR (time domain reflectometer), not something found in the average DIYer's
toolkit.

If the open is "dirty" (grounded), the use of a ground fault locator is in
order. Of course, that is also something not found in the average DIYer's bag.

I expect that neither of these testers is available at even the more
widely-stocked rental place. Even if they were, successfully using such
sophisticated test equipment is probably beyond the capability of a
first/only-time user.

You would well to consider REPLACING the line.

Any effort made and expense incurred in repairing the existing line, if
directed instead at replacing the line, would effectively reduce the cost of
replacement. ...and that is IF you are successful in repairing the old line -
certainly not a "given". Good luck.
--

JR

Climb poles and dig holes
Have staplegun, will travel


  #6   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 8,803
Default Homebrew underground wire break locator.


"Don Young" wrote in message
...

"HeyBub" wrote in message
...
Bob F wrote:
My father has a underground wire to a panel in his garage from his
house. One lead of the 220V service has apparently "opened" somewhere
underground. It is probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We
suspect that a splice was made in the wire someplace that may have
failed.
Can anyone offer any good ideas for a way to locate the break without
digging the whole thing up? Maybe something using a transister radio
as a locator and a relay buzzer or something as a signal source.


There are cheap voltage proximity detectors (I've got one about the size of a
pen); they cost about $10.

You can do a binary sort. Dig down to the cable at the 50' point. Any
voltage? If not, the break is between the 50' mark and the source. Move
toward the source to the 25' mark and dig down to the cable again.

Rinse. Lather. Repeat.

A good idea but may not work if the break is only in the neutral wire. It
might be possible to locate a neutral break by temporarily reversing the wires
so the neutral is hot.


I can get to the wires at either end. for connections or re-connections.

Bob


  #7   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 8,803
Default Homebrew underground wire break locator.


"shiver" [email protected] wrote in message
...
"HeyBub" wrote in
:

Bob F wrote:
My father has a underground wire to a panel in his garage from his
house. One lead of the 220V service has apparently "opened" somewhere
underground. It is probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We
suspect that a splice was made in the wire someplace that may have
failed.
Can anyone offer any good ideas for a way to locate the break without
digging the whole thing up? Maybe something using a transister radio
as a locator and a relay buzzer or something as a signal source.


There are cheap voltage proximity detectors (I've got one about the
size of a pen); they cost about $10.

You can do a binary sort. Dig down to the cable at the 50' point. Any
voltage? If not, the break is between the 50' mark and the source.
Move toward the source to the 25' mark and dig down to the cable
again.

Rinse. Lather. Repeat.


Binary search is the best way to physically minimize your effort.
If you have any skill with electronics, you can try this:
http://www.uoguelph.ca/~antoon/circ/foxhound.html
Or, just get the equipment from Triplett.


That's a helpful reference. I might even have the parts to breadboard that.

OR, I have a signal generator that starts at 100KHz. I'll have to experiment
with that.

Bob


  #8   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 8,803
Default Homebrew underground wire break locator.


"Jim Redelfs" wrote in message
...
In article ,
"Bob F" wrote:

We suspect that a splice was made in the wire
Can anyone offer any good ideas for a way to locate the break


If the open is "clean", that is, NOT grounded or crossed, you can determine
the distance-to-open from either direction and use that information to
determine where to dig. Of course, such testing generally requires the use of
a TDR (time domain reflectometer), not something found in the average DIYer's
toolkit.


Any easy way to fake a TDR with a signal generator and an oscilloscope?

Bob


  #9   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 76
Default Homebrew underground wire break locator.


"Bob F" wrote in message
. ..

"Jim Redelfs" wrote in message
...
In article ,
"Bob F" wrote:

We suspect that a splice was made in the wire
Can anyone offer any good ideas for a way to locate the break


If the open is "clean", that is, NOT grounded or crossed, you can determine
the distance-to-open from either direction and use that information to
determine where to dig. Of course, such testing generally requires the use of
a TDR (time domain reflectometer), not something found in the average DIYer's
toolkit.


Any easy way to fake a TDR with a signal generator and an oscilloscope?

Bob



Yes...


  #10   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 8,803
Default Homebrew underground wire break locator.


"Rick" wrote in message
...

"Bob F" wrote in message
. ..

"Jim Redelfs" wrote in message
...
In article ,
"Bob F" wrote:

We suspect that a splice was made in the wire
Can anyone offer any good ideas for a way to locate the break

If the open is "clean", that is, NOT grounded or crossed, you can determine
the distance-to-open from either direction and use that information to
determine where to dig. Of course, such testing generally requires the use
of
a TDR (time domain reflectometer), not something found in the average
DIYer's
toolkit.


Any easy way to fake a TDR with a signal generator and an oscilloscope?

Bob



Yes...


Thanks!

Bob




  #11   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 664
Default Homebrew underground wire break locator.

In article ,
"Bob F" wrote:

Any easy way to fake a TDR with a signal generator and an oscilloscope?


Possibly, but that is beyond MY capabilities. I'm just a telco grunt that
USES the equipment. I know little about HOW it works. It took all I could
muster to remember that I want to recommend a TDR and, even more, what the
acronymn stands for. grin Please let us know how it ends up.
--

JR
  #12   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 76
Default Homebrew underground wire break locator.


"Bob F" wrote in message
...

"Rick" wrote in message
...

"Bob F" wrote in message
. ..

"Jim Redelfs" wrote in message
...
In article ,
"Bob F" wrote:

We suspect that a splice was made in the wire
Can anyone offer any good ideas for a way to locate the break

If the open is "clean", that is, NOT grounded or crossed, you can determine
the distance-to-open from either direction and use that information to
determine where to dig. Of course, such testing generally requires the use
of
a TDR (time domain reflectometer), not something found in the average
DIYer's
toolkit.


Any easy way to fake a TDR with a signal generator and an oscilloscope?

Bob



Yes...


Thanks!

Bob


You're welcome...


Do a search of TDR with a 555 timer, etc..then find or measure the characteristic
impedance and velocity factor of the cable. That might get you close, assuming you know
how the cable is run. If not, an RF generator and radio can trace the location.

Or just dig like others suggest.


  #13   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 1,447
Default Homebrew underground wire break locator.

On Nov 5, 10:56 pm, "Bob F" wrote:
My father has a underground wire to a panel in his garage from his house. One
lead of the 220V service has apparently "opened" somewhere underground. It is
probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We suspect
that a splice was made in the wire someplace that may have failed.

Can anyone offer any good ideas for a way to locate the break without digging
the whole thing up? Maybe something using a transister radio as a locator and a
relay buzzer or something as a signal source.

Bob


Before digging I'd try something along these lines.
Disconnect the 3 wires (Assuming it is North America? two hot and one
neutral???) wires at both ends. Leave any ground connected.
Using a multimeter that has a 'capacitance measurement' measure the
capacitance of each wire with reference to the ground wire from both
ends.
If you find that say wire A has 0.2 microfarads and wire B has 0.1
micro farads and is roughly the same ratio from both ends B is broken
somewhere around the middle. Etc. We have an electricians quality DMM
(Digital multimeter) that measures capacity. You may be able to
borrow?
Have never done this, but many years ago did so using a 'telephone
Test board' meter and DC supply reversing switch keys, to find open
circuits in telephone lines. Wet leakage to ground and stray currents
often made it difficult though.
Any help?

  #14   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 8,803
Default Homebrew underground wire break locator.


"terry" wrote in message
ups.com...
On Nov 5, 10:56 pm, "Bob F" wrote:
My father has a underground wire to a panel in his garage from his house. One
lead of the 220V service has apparently "opened" somewhere underground. It is
probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We suspect
that a splice was made in the wire someplace that may have failed.

Can anyone offer any good ideas for a way to locate the break without digging
the whole thing up? Maybe something using a transister radio as a locator and
a
relay buzzer or something as a signal source.

Bob


Before digging I'd try something along these lines.
Disconnect the 3 wires (Assuming it is North America? two hot and one
neutral???) wires at both ends. Leave any ground connected.
Using a multimeter that has a 'capacitance measurement' measure the
capacitance of each wire with reference to the ground wire from both
ends.
If you find that say wire A has 0.2 microfarads and wire B has 0.1
micro farads and is roughly the same ratio from both ends B is broken
somewhere around the middle. Etc. We have an electricians quality DMM
(Digital multimeter) that measures capacity. You may be able to
borrow?
Have never done this, but many years ago did so using a 'telephone
Test board' meter and DC supply reversing switch keys, to find open
circuits in telephone lines. Wet leakage to ground and stray currents
often made it difficult though.
Any help?

I had a meter that measured capacitance, but it died. But this is definately
worth checking out. Thanks.

Bob


  #15   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 375
Default Homebrew underground wire break locator.

"Bob F" wrote in message
. ..
My father has a underground wire to a panel in his garage from his house.
One lead of the 220V service has apparently "opened" somewhere
underground. It is probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We
suspect that a splice was made in the wire someplace that may have failed.

Can anyone offer any good ideas for a way to locate the break without
digging the whole thing up? Maybe something using a transister radio as a
locator and a relay buzzer or something as a signal source.

Bob




Not exactly homebrew, but a "time domain reflectometer" will do the job.
It's a piece of highly specialized equipment.

http://en.wikipedia.org/wiki/Time-domain_reflectometer



  #16   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 8,803
Default Homebrew underground wire break locator.


"Bob F" wrote in message
. ..
My father has a underground wire to a panel in his garage from his house. One
lead of the 220V service has apparently "opened" somewhere underground. It is
probably about 100 feet long.

I'd love to trace the break so I can dig it up next time I visit. We suspect
that a splice was made in the wire someplace that may have failed.

Can anyone offer any good ideas for a way to locate the break without digging
the whole thing up? Maybe something using a transister radio as a locator and
a relay buzzer or something as a signal source.


Thanks everyone for all the ideas. I did some experimentation today with my
signal generator and an AM radio. I'm hopeful this will work, and hopefully will
get over to try it for real this weekend.

Bob


Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Does coating stranded copper wire with solder cause any issues or break any codes? Harry Muscle Home Repair 173 February 16th 06 01:27 AM
Does coating stranded copper wire with solder cause any issues or break any codes? Billy H Home Repair 4 February 5th 06 08:42 PM
Wire type needed for underground C & M Home Repair 5 July 22nd 05 11:17 PM
repair underground wire insulation Karl Townsend Metalworking 8 April 26th 04 04:12 AM
Dimming Lights in Barn (underground wire) Charles Home Repair 3 January 16th 04 06:04 PM


All times are GMT +1. The time now is 04:57 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"