Broken U/G conduit.... am I missing something ?

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Since you have a string in it, could pull back a #12 stranded, and use an underground tracer to see if it makes any weird turns or offsets. That might give an indication of where a possible location of the problem may be.

Already tried that with a fish tape I pushed in.

The problem is that the two empty conduits share a trench with 8 sets of 750 feeders; once you hit that section of trench, my wand can’t detect the pulse. It’s overpowered by the energized feeders.

These feeders run along with the empty conduit up until the last maybe 100’.


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DUDE! Here it is.
Buy it here.
 
DUDE! Here it is.
Buy it here.
That might be the ticket! Lucky he has PVC and not metal conduit!
 
In an earlier post in this thread I mentioned the cable ferret, but something with onboard recording. Its wifi and the signal might not make it through a few feet of soil + pavement.
 
It says wireless up to 40'. You would have to follow the cable ferret while it is pulled through the conduit. This also assumes its broadcast can get through the earth, concrete, asphalt.
I kind of figured one would have to follow the camera with the phone for the very reason you mentioned. WiFi rated for 40' should be able to get through dirt and concrete cover at a few feet. For $175 I sure would try it.
 
I kind of figured one would have to follow the camera with the phone for the very reason you mentioned. WiFi rated for 40' should be able to get through dirt and concrete cover at a few feet. For $175 I sure would try it.
When I click on the link it comes up $129.99 .

And if it works and he sees a pull box or pit, he would know about where to look.
 
Already tried that with a fish tape I pushed in.

The problem is that the two empty conduits share a trench with 8 sets of 750 feeders; once you hit that section of trench, my wand can’t detect the pulse. It’s overpowered by the energized feeders.

These feeders run along with the empty conduit up until the last maybe 100’.


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What kind tracer are you using? Something that is in a passive 60 Hz mode will have difficulty, something that uses higher frequency should not have much difficulty as long as what you are tracing is electrically isolated from other items in the vicinity. If you fish tape were contacting a grounded enclosure then you would be placing the signal on the grounded conductors in adjacent raceways.
 
What kind tracer are you using? Something that is in a passive 60 Hz mode will have difficulty, something that uses higher frequency should not have much difficulty as long as what you are tracing is electrically isolated from other items in the vicinity. If you fish tape were contacting a grounded enclosure then you would be placing the signal on the grounded conductors in adjacent raceways.
Yeah, insulated wire should give a stronger signal too. Water in the pipe will bleed the signal out. That’s what I like about my Amprobe tracer, it does not bleed onto other lines. It supposedly will trace up to 8’ deep, but about three foot is the most I’ve been able to get.
 
Yeah, insulated wire should give a stronger signal too. Water in the pipe will bleed the signal out. That’s what I like about my Amprobe tracer, it does not bleed onto other lines. It supposedly will trace up to 8’ deep, but about three foot is the most I’ve been able to get.
And if you have an Amprobe, Extech like the one below, or a similar one that can do a "loop mode" test then I think you have a better chance of detecting the signal in this situation. In a loop mode test the transmitter is sending a current through the wire in a closed circuit to generate a magnetic field, instead of applying a voltage to an open-ended wire to generate an electric field. Water and damp dirt will attenuate an electric field quickly but less so with a magnetic field. Also, as hillbilly1 indicated, a bare conductor surrounded by water will load down the transmitter and hence lower the applied signal voltage especially with the open-ended wire approach. The loop mode should be less effected from using a bare wire (because it operates with a lower impedance level) but usingt an insulated wire would still be better.

I think the tracers that can do loop mode testing are likely to have a wider probe on the receiver because they need a small internal coil to sense a magnetic field. The pointy probes are probably only good for detecting electric fields created by a voltage applied to an open-ended wire.
Loop mode testing is shown on page 9 of the Amprobe manual linked below (page 11 of the pdf). You could complete the "loop" in this test by referencing the transmitter to a small ground rod, and also attaching another ground rod at the far end of the wire (as shown on the right side of fig. 2.2b on that page of the manual). You might be able to get an even bigger signal by using another conductor instead of the earth to complete the loop, and moving that conductor at least several feet away from the conduit.


 
What kind tracer are you using? Something that is in a passive 60 Hz mode will have difficulty, something that uses higher frequency should not have much difficulty as long as what you are tracing is electrically isolated from other items in the vicinity. If you fish tape were contacting a grounded enclosure then you would be placing the signal on the grounded conductors in adjacent raceways.

Amprobe AT-3500


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