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New Member


Sunday, July 19th 2020, 8:46pm

Voltage drop

New to the site. There's alot of sprinkler knowledge being thrown around here and I am a good listener who loves to learn.
Learned alot on my own but I still have a question or two.

I have a 7 zone system with a Hunter Xcore controller. Everything works fine except Zone 4 decided to stop working. Through researching the internet on how to troubleshoot this problem, I've narrowed it down to having a "nicked" or almost cut field wire to the zone 4 solenoid. With the zone not running, I get the same voltage reading as the controller puts out to that zone. But when the controller kicks in for that zone, the voltage reading goes down to 6-7 volts. Solenoid won't open. Correct me if i'm wrong.

Here's one of my questions.
Would one of those Valve and wire locators being able to find the damaged wire so I don't have to dig a trench and lay new wire? I know where all my valves are. They are scattered in various places. I just don't know if zone 4 wire follows the route of the valves. They seem to laid out in a line all the way around the house and end up in the front yard, with Zone 4 being the last one. Which leads to my next question......

The wires coming out of my controller are color coded. 10 wire cable. It travels down the pvc pipe, through the wall, then down into the ground. At all the valves, there is only red and white wires. Question is...
Where is the splice from the colored wires to the red/white wires? There's no box that I can tell. May be just a bad connection at that splice. But where is it? And why would anyone install a sprinkler system like this? Why not run the entire distance with the cable you started with out of the controller? I know it's to save money but....jeez. ?(

Sorry to be long winded, but I like detail. :D



Posts: 2,500

Location: USA


Sunday, July 19th 2020, 9:28pm

You've confused me a bit. Quite a bit. lol You say you get the same reading with the timer on or off. Then you contradict that statement saying the reading drops when it's on.

Are you testing for Ohms or Volts? Ohms determines the condition of the wiring or solenoid. There should be no voltage reading with the controller off.

Just as a possible time saver, try swapping solenoids with a valve that works.

I've seen the wiring you've described on numerous occasions. People just use what they have sometimes.


New Member


Monday, July 20th 2020, 7:53am

Ok. Let me clarify.

When I check the voltage, with the solenoid disconnected, at the valve, controller on, I get the same voltage reading as the controller puts out to that zone.

When I hook the solenoid back up, and energize the solenoid, is when it drops. In other words, put a load on it.

Went ahead and replaced solenoid and diaphragm to rule those out. Sprinkler parts are cheap. Now I have spares. LOL.
I've also tried the swap to a working zone next to it and zone 4 runs great. This was after I ruled out the common. Cause I thought I might get lucky and just have to jump the common over from that nearby working zone. So that tells me it is the field wire, directly from the controller.



Posts: 2,500

Location: USA


Tuesday, July 21st 2020, 2:17am

Sounded like the solenoid but you tried that already.
A wire tracer/valve locator might find the problem. It's very difficult. You might be able to find the bundle of splices with it.
an A-frame fault finder is the ticket. You'll need to hire a pro to use it. Or you can look at youtube videos. It can be simple or maybe not.
Maybe follow the wires until you find the splices. No guarantee that's where the problem is though. Do any digging that may have nicked the wires?


New Member


Wednesday, July 22nd 2020, 8:47am

Not gonna spend a lot of money on this. In the meantime, I will just go out in the front yard, reach down in the valve hole, turn it on manually. Then go in the house, and tell Alexa to give me a "XX" minute timer. :D


Supreme Member

Posts: 5,352

Location: Metro NYC


Friday, July 24th 2020, 6:41am

There is a way to trace a nick in a wire, but it employs some complicated instrumentation that takes time to learn how to use.

For the least amount of money spent, the homeowner solution to wiring issues in the field is almost always to dig in a new cable, with spare conductors for future issues.


New Member


Friday, July 24th 2020, 8:28am

For all the time, cost, and labor involved in solving issues like this, seems like the installers would insist on doing it right the first time and lay the right cable "all the way" so there would be "spares". At least, that's how I would do it. Provides an easy fix down the road if issues arise. Just swap a wire at the controller and swap a wire at the solenoid.

TA-DAAA!!!! :thumbsup:

Appreciate everyone's input. Thanks


Starting Member


Monday, February 1st 2021, 10:44am

Hi.... What is the voltage at the loop when invigorated? What might be said about with the loop separated? I'll wager there is an enormous contrast.

You can diminish the voltage drop by sending 120v on the UF and venturing down at the loop. The 5-overlay increment in voltage will bring about 1/fifth the current, with a similar wattage curl.

In the event that the control box just puts out 24v, you can utilize that to control a transfer that thusly switches the 120v to the loop. So far as that is concerned, in the event that you have 240v convenient, you could even utilize a 240v loop.

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