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Waterlogged
07-25-2012, 10:09 PM
Another thanks to Jim.
He was nice enough to loan me his TDR for a couple of months, to try it out. I have to say it worked quite well for me.
This is how I got started. I measured the distance to some known valves and using those numbers, I reset the VOP to 18%. This gave me real close numbers for the distance of some known valves.

I took it on a service call. I was told that four valves in the front didn't work; Two valves in the back did. Hooked the TDR to one of the zones in the front. It gave me a length of 10 ft. (1st photo)

While I was at the controller I decided to see how close the two good valves were; the readings were 66 and 68 and the actual distances were 33 ft and 34 ft. respectively (photos 2 and 3) They were right on.

Turns out the two valves in the back had been rewired at one point, so I had two wire paths. The 10ft length was under concrete, next to a huge tree.

I found the common on the second wire path (to the valves that are in the front). I ran a line to the two good valves in the back. Everything works now.

My total time couldn't have been more than an hour and 15 min.


Used it on the second call. Two valves not working. Different locations in the yard. Hooked the TDR up to one zone wire; said it was 20ft away. Hooked the TDR to the second zone wire; said it was 20 ft away. Hooked the 521 up, went 20 ft and this is what I found. (photo 4) The installation of the termite bait had cut the two wires to the front yard. This one also had two wire paths, the back yard was added after the front.

I think the TDR is going to be a great tool in combination with my other resources. It might even make it to the front of the line.

TuffWork
07-25-2012, 10:20 PM
Nice. I've been considering the cost of an A Frame from time to time. I don't think this could completely replace one, but could be a good alternative if someone doesn't happen to have a spare grand laying around to buy something that they would only use occasionally.

1idejim
07-26-2012, 01:33 AM
A TDR won't nor is it meant to replace locators or fault finding equipment, nor were they intended to be used for low voltage irrigation. TDRs were developed for discovering wire taps during one of the wars to end all wars.

I just happen to be stubborn enough to believe that they make a fine compliment to irrigation locating and fault finding equipment.

Every serious troublshooting tech should own a manual multimeter, a leakage clampmeter, a stationmaster, an inductive amplifier, a TDR, a locator and a fault finder.

All that said, very few troubleshooters feel the same way i do and many don't own any of the above tools or instruments.

Using a Tdr on a locate enables one to narrow the search area from thousands of feet to tens of feet, to organize the valves in their order of physical placement and in many situations allows the locating tech to avoid wasted time by finding unknows like buried J boxes and ganged valves.

Glad you're happy with the TDR waterlogged!
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greenmonster304
07-26-2012, 06:35 AM
Every serious troublshooting tech should own a manual multimeter, a leakage clampmeter, a stationmaster, an inductive amplifier, a TDR, a locator and a fault finder.

All that said, very few troubleshooters feel the same way i do and many don't own any of the above tools or instruments.

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It's funny you say that. Last year I saw a buddy of mine at the supply house. I was there hoping they had a multimeter because mine wasn't working but they didnt have one. So I ask my friend if I could borrow his for an hour or so for my next call. He said I don't have one. I said how do you test for voltage and stuff like that. He said he just uses a good solenoid to test. I couldn't believe it.
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Kiril
07-26-2012, 07:56 AM
So I ask my friend if I could borrow his for an hour or so for my next call. He said I don't have one. I said how do you test for voltage and stuff like that. He said he just uses a good solenoid to test. I couldn't believe it.

I use my tongue. :dancing:

1idejim
07-26-2012, 08:47 AM
I use my tongue. :dancing:

Apple didn't fall far from the airstream brother.

:::LMMFAOITSOJ:::
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ASI
07-26-2012, 07:02 PM
The TDR is a great TOOL and so is 1idejim for lending it to you. :usflag:

The thing I like about the TDR is within minutes you will have the lay out of the valves in the system. With the TDR no more hoping you can find the valves, you know that you can find the valves that need to be repaired.

Watterlogged
Can you please post the type and gauge of wire you were testing using 18% as the VOP?

1idejim
07-26-2012, 07:38 PM
It's funny you say that. Last year I saw a buddy of mine at the supply house. I was there hoping they had a multimeter because mine wasn't working but they didnt have one. So I ask my friend if I could borrow his for an hour or so for my next call. He said I don't have one. I said how do you test for voltage and stuff like that. He said he just uses a good solenoid to test. I couldn't believe it.
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took a call today from a former regular client with a missing valve at a commercial site, "did you happen to check the condition of the valve?" NO.

Waterlogged
07-26-2012, 08:26 PM
ASI,
It so happens that everything I've worked on so far has had multi strand from the controller to outside the garage (22G) and converts to (16G) single strand.
I understand that if I come across a different size of wire, my VOP may be different. And it will just take more practice to dial in the VOP.

If it makes any difference, we have mostly clay soil. And the valves are spread out, throughout the yard here.

1idejim
07-26-2012, 11:05 PM
The TDR is a great TOOL and so is 1idejim for lending it to you. :usflag:
Thank you. With the TDR no more hoping you can find the valves, you know that you can find the valves that need to be repaired.


I was always confident in my abilities but with a TDR in the arsenal you know you are going to find the valve or compromise, it's more a matter of how fast you find it.
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