Irrigation electrical issue Cancel The title field is required!

1. Keith Lamb

   

   3 posts
   
   3/15/2012 6:03 PM

   I've been dealing with a very frustrating electrical issue for the past 4 days. One of the 120v lines that powers 10 of my clocks (Rainbird Par+) keeps tripping the breaker (20a). It can take anywhere from 2-10 hours for this to happen after re-energizing the circuit breaker. I've checked every splice/junction on the run and for voltage get 115-118v on the hot, 0-0.1 on the ground and at the closest clock from the circuit breaker get 1-1.5v on the neutral with the voltage increasing on the neutral the farther I get from the circuit breaker(2nd clock 2v, 3rd clock 2.8v, 3rd, 4th, 5th clocks(on lateral lines from main power) reading 3.2-3.5, 6th clock 6v, 7th & 8th clocks 7.1v, 9th clock 8.5 and the 10th clock reading at 10v. Obviously if it was a dead fault then it would be easy to find, but I'm thinking I dealing with a possible fault to earth ground....maybe a small nick in the hot wire wire...I don't know.
   
   We thought that we might have a transformer(s) going bad in a clock so I installed 1a circuit breakers in all the clocks and none of those have tripped. We tested the amp load at the power source and the line was only drawing 2.2a under no load. Almost every time the breaker has tripped it has not been under load. I installed a new 20a breaker. Running out of ideas.
   
   I've had one of my members who, is a electrician, look at it and he is baffled also. He is going to try and get a hold of the megometer his company has and see if this can help find the problem.
   
   Any ideas or suggestions are welcome......I'm begging you!! LOL.

   
   
   
   
2. Mark Van Lienden

   

   14 posts
   
   3/16/2012 8:03 AM

   Kieth, First thing I would do is switch the circuit breaker and see if the problem moves.Then is it happening during irrigation?I had a sprinkler last year that would blow the ground fuse at the clock every time it would come on.We also have a grond plate in the ground and they reccommend that it be kept moist.Then could you isloate clocks by disconnecting the farthest and if that still trips disconnect the second farthest ect to see if it is in a clock.

   
   
   
   
3. McCallum David K

   
   3/16/2012 9:03 AM

   Keith battling almost the exact same issue........repaired a leak not long ago and we are going back in that hole Monday to see if we nicked the power wire and causing a ground fault. Only affects two holes for us and able to water manually but I feel your frustration. Hope we solve ours Monday.

   
   
   
   
4. Jon Gansen

   

   1 posts
   
   3/16/2012 9:03 AM

   My assistant had a few ideas and questions hes pretty good and diagnosing here goes. Just throwing around some ideas.
   
   How old is the system? Any additions or digging along the run?
   
   What gauge wire are you using in your run?
   
   Double check all your grounding points from start of run to finish to see if the connection is clean and tight.
   
   While using the 20a breaker test each station until it pops, write down the station it was on when the breaker tripped then start the process over and keep record of your results. It might narrow it down to an area where your problem is.
   
   Maybe try a 30a-40a breaker and see if it gets hot somewhere in your line to isolate the problem. If you find the problem fix it then change it back to the 20a.
   
   
   Maybe you and the electrician have already looked into these ideas. I know electrical can be a pain at times but its the best I can do without looking over the solution myself.

   
   
   
   
5. Mike Hundley

   

   0 posts
   
   3/16/2012 8:03 PM

   We have this problem often. Usually I will unhook the power wire from the breaker and unhook at the first satellite and run a continuity test between the power and ground wire. You can continue to do this through your run from satellite to satellite. Eventually you will likely have continuity between the two somewhere through the run. Then you will have to use a break locator to find the break. This will at least determine an area that you can focus on. Good luck. They can be frustrating for sure.

   
   
   
   
6. Mike Hundley

   

   0 posts
   
   3/16/2012 8:03 PM

   Probably should also include the neutral in the mix of continuity tests for good measure if your neutral is actually used.

   
   
   
   
7. Mike Hundley

   

   0 posts
   
   3/16/2012 8:03 PM

   Alos make sure you unhook your power wire from satellite to satellite so that you are only performing tests on the wire running from satellite to satellite and not from circuit braker all the way to second satellite. In other words, circuit breaker to 1st satellite, 1st satellite to second satellite, and so on.

   
   
   
   
8. Jack Tripp

   

   3 posts
   
   3/16/2012 9:03 PM

   A ohm meter is much better than a continuity test for finding a break. A continuity test is going to tell you if flow is getting through the wire, but not how much flow (think of it this way a 2" pipe with a gate valve fully open and a 2" pipe with a gate valve half closed can have the same static psi if you don't have any flow going through the line). Ohms is going to tell you how much resistance there is to the flow of electricity. If their is a big break or a slight break there is going to be a bigger resistance to the flow than a good wire. The ohm reading number is going to be higher the larger the break.
   
   To do an ohm reading disconnect the wires from the power source and then wire nut two of the three wires together at the other end. With an ohm meter you can determine the resistance on those two wires. You can compare that to tying the two other combinations together.
   
   1st white/black wires
   2nd white/green wires
   3rd black/green wires
   this assumes all three wires are the same gauge
   
   If wanted to know the resistance (ohms) of the wire per foot you would have to go the manufacturer or some table to look up that figure.
   
   You probably will have to disconnect the wires between satellites to be able to isolate things to get a good ohm reading.
   
   Once you find out which wire is leaking you will have to use a wire locator which can find a ground fault. Your irrigation supplier may offer this service. Try googling ground fault locator if you want to know what one looks like.
   
   Good Luck!
   
   Jack Tripp
   La Crosse Country Club
   Onalaska, WI

   
   
   
   
9. Dinger Greg

   
   3/17/2012 8:03 PM

   Solid advice from Jack "Tripp".
   
   After repeated trips, a breakers "trip curve" can begin to deteriorate. Not sure how many trips that is, but something to bear in mind as you troubleshoot.
   
   You could always throw a 40a in there and go look for the smoke. Had an instructor in tech school show us that on a semi trailer once, he called it the "smoke show". Maybe not recommended.

   
   
   
   
10. Keith Lamb

    

    3 posts
    
    3/18/2012 3:03 PM

    Thanks everyone. Will let you know what happens.

    
    
    
    
11. Kevin Girt

    

    0 posts
    
    3/19/2012 7:03 PM

    Keith,
    By no means put in a bigger breaker, install a NEW 20 amp breaker and see if you continue to have a problem, The last thing you want to do is fry all of your transformers. I had 30 years experience dealing with crappy irrigation installations.
    Kevin

    
    
    
    
12. Robert Crockett

    

    4 posts
    
    3/19/2012 8:03 PM

    Kevin Girt said: Keith,
    By no means put in a bigger breaker, install a NEW 20 amp breaker and see if you continue to have a problem, The last thing you want to do is fry all of your transformers. I had 30 years experience dealing with crappy irrigation installations.
    Kevin

    
    Ditto on the breaker...2yrs as an electrician...benefits...all the shock treatment you wanted for free

    
    
    
    
13. Jack Tripp

    

    3 posts
    
    3/19/2012 9:03 PM

    Another idea.
    
    Have you tried putting an amp meter on the electric line and see how many amps you are actually pulling. If you are pulling more than 20 amps the breaker is going to trip.
    
    If you are pulling more than 20 amps disconnect all satellites from the electric line and add one back on line at a time taking an amp reading each time.
    
    Jack Tripp
    La Crosse Country Club
    Onalaska, WI

    
    
    
    
14. Dinger Greg

    
    3/20/2012 7:03 AM

    Jack Tripp, CGCS said: If you are pulling more than 20 amps the breaker is going to trip.

    
    
    Not necessarily always. It could sit there and marinate around 20-25 amps for hours to indefinitely. On the other hand, a direct short to ground should trip it within half a cycle (ac). If he's seeing anywhere from 2-10 hours before it goes, he might see 25-40 amps being drawn.
    
    Great idea on the ammmeter though. He could sure narrow it down a lot using Jack's suggestion.

    
    
    
    
15. Keith Lamb

    

    3 posts
    
    3/20/2012 8:03 AM

    Alrighty guys.
    
    We have solved it. Apparently when this course was owned by American Golf some years ago a nitwit executive from AG came out here and decided that this "Links" course didn't have enough trees. He had 1500 pines delivered and ordered them to plant them all over the course. After continuing to eliminate areas working our way back to the power source we got a dead fault yesterday afternoon that we traced to, you guessed it, directly below one of these god forsaken trees. It looks like the root system had caused a earth ground fault on the hot wire and it finally got hot enough to cause a dead fault. Those are easy to find. Breaker started to trip instantaneously. The baffling thing we were seeing was that the voltage was always good (118-115v), there was very little voltage on the neutral, no voltage on the ground and the line was only pulling 2.2 amps under no load and 3-4 amps under normal load. I even stood there the other day and it tripped in front of me so I immediately reset it and put my clamp amp meter on it and it was reading 2.2 amps. We did many of the things you guys suggested...replacing breaker, moving breaker, etc... We are going out today to pull a new power wire around those trees and I have signed the death warrant for those 2 trees as not only are they on top of the power wire, but also on top of one of my main irrigation lines.
    
    Thanks to everyone for all your responses and suggestions. I knew I could count on the brotherhood.