Weird Troubles

Discussion in 'Landscape Lighting' started by steveparrott, Apr 19, 2010.

  1. steveparrott

    steveparrott Sponsor
    Posts: 1,189

    The recent troubleshooting thread was a good brain teaser - also educational.

    Would anyone else like to share weird system failure stories and how you solved the problem?
     
  2. Pro-Scapes

    Pro-Scapes LawnSite Platinum Member
    Posts: 4,181

  3. steveparrott

    steveparrott Sponsor
    Posts: 1,189

    See if you can solve this problem. This stumped us for awhile. Double kudos to the first one to name the cause and solution. (This one is good to know, and might change the way you do things.)

    A system with about 30 fixtures, 7 home run wires to a 1200W transformer. The system operates normally, however, if one of the common breakers was switched off, the lights on that common did not turn off - they glowed, and measured 5 volts at each of the fixtures. Why?
     
  4. Alan B

    Alan B Sponsor
    Posts: 410

    (erased my guess... I'll leave it for others)
     
    Last edited: Apr 19, 2010
  5. RLI Electric

    RLI Electric LawnSite Senior Member
    Posts: 381

    Steve, I think you have a short to ground. If you could gfci the secondary side it would have tripped (see earlier posts about that). To isolate that you would go to the goofy run and take a fixture offline. The fact that all of them are doing it on that particular homerun may mean that the short is in the actual homerun itself. That is my guess.
     
  6. steveparrott

    steveparrott Sponsor
    Posts: 1,189

    Bob, it could have been that but it wasn't. No shorts, no malfunctions. The cause really surprised us. Any other takers?
     
  7. RLI Electric

    RLI Electric LawnSite Senior Member
    Posts: 381

    Reversed polarity on one of the fixtures?
     
  8. irrig8r

    irrig8r LawnSite Platinum Member
    Posts: 4,535

    Voltage crossing from one cable close to another through thin or nicked insulation where they share close quarters in the transformer?

    Weak inductive load from the transformer coil passing to the home run cables?
     
  9. steveparrott

    steveparrott Sponsor
    Posts: 1,189

    No winners yet. A clue - the suspect common was shared by two wire runs. Switching one of the runs to another common solved the problem.
     
  10. The Lighting Geek

    The Lighting Geek LawnSite Senior Member
    Posts: 875

    the commons were connected to 12v by accident?
     

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