Invisible Dog Fence - Break/Partial Break Detection

Hi All,

I have an invisible dog fence that worked fine for 3 years. 4 weeks ago I had an irrigation company run new sprinkler lines and it looks like they mangled my fence. The irrigation company is useless and I gave up chasing after them.

So, I got out there and started fixing the fence myself. After finding 3 complete line breaks I plugged my transmitter back in and unfortunately it still beeps. I can't seem to find any other breaks. I suspect I may have a partial break. I am unable to find any good tools to find the remaining issues.

I finally gave in today and called the dog fence company and they are going to charge me $75 for the initial service fee + $20 per splice and $25 per $15 minute increment of labor time.

Now, this is my last ditch attempt to fix this myself. Any thoughts on how i can find my remaining fence issues? I have a Kolsol Underground Wire Locator that I bought from Amazon to help find the complete breaks. Any tips, suggestions, etc would be appreciated. I need to get my fence back up and running as its the only way to stop my dogs from chasing wild animals.

 

You'll probably need a tester with a TDR function to find the partial break. It measures the time electrical pulses take to reflect off the end of the cable and can compute how many meters away the break is.

I suspect the fence servicing company will have one as that has got to be a big part of their business. They used to be outrageously expensive, but the feature is starting to show up in the entry/mid level Pro equipment.

 

Thanks Ben.

Any recommendations on a tester? I looked and there seems to be a wide variety. I am still researching, but if you have suggestions please share.

One last dumb question; if I use the wire locator I have (the Kolsol) and just want to send signal starting from one end of the loop would I just connect the red wire to the fence wire and clip the black wire to a ground?

 

Years and years ago, a fence company showed me how to find the break. They attached an inductor (I have no idea what size/type) between the two terminals of the main power box (going out to the wire loop). Then use an AM radio with antenna and tune it to the frequency that you hear the beeping (modulated tone) coming from the wire loop.

Then just walk around the loop slowly. When you hear the beeping decrease, you're getting close to a break.

I know it's not a hugely helpful set of instructions, but it might point you in the right direction.

 

Sorry I don't have a specific recommendation for a tester. The equipment I'm familiar with is more "pro" grade and would be much more expensive than the service call from the fence company. I just did a quick Google for testers, and it seems like you can get a TDR that claims 1% accuracy for ~$200. Can't say how well it works or if the manufacturer's claims are accurate.

Yes that should work for the wire locator. I would also disconnect it from the fence transmitter just to make sure you don't cause any damage to the fence transmitter. The fence wire should only be located right under the sod so it should be very easy to track with that Kolsol.

 

One other possible idea is that you might have to isolate the portions of the loop that are twisted -- mainly between the transmitter and the outermost loop. It's possible to have a break or short in the twisted pair that would be confusing for your tracer as the whole point of the twisted section is to cancel the fence signal. Add to that inductive coupling and it might be confusing to interpret the test results.

 

A TDR just give you distance. It's not really a locator.

 

Yes that's a good point I glossed over. You need the TDR to tell you how far away the break is, then you need a locator and tape measure to walk that many feet down the path of the wire to find the break.

 

We have locators to find underground faults but they are thousands of dollars. You might be better off running a new wire for the invisible fence then trying to find the fault as there will likely be more than one.

We locate and repair underground faults all the time that are caused by irragation and excavation companies. Typically they will never take responsibility for the damage and many cases will not tell anyone when it happens. Worse yet they will "repair" it themselfs which will fail in a couple of years.

 

Here's the details of using a choke and AM radio to find the break. They explain it much better than I do.

https://www.instructables.com/id/How...ble-dog-fence/

 

It shouldn't be that hard. You know where the fence runs. You know where the sprinklers were run. Any place they cross or come close should be suspect.