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Voltage at the tap too high, 150 w transformer

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    Voltage at the tap too high, 150 w transformer

    150 watt transformer w 3 fixtures, each w 20 w halogen lamps. First fixture (at the middle of the run, where we T) is 15 feet from transformer. The other 2 fixtures are 15 feet from the T. So this is a very close system.

    We are getting a 13.6 v reading at the 12 tap, causing the lamps to burn bluish green. We coiled 30 ft of 12/2g wire, and placed that between the tap and the primary wire, with no reduction in volts. So we tried, first, a coil of 14/2g, then 16/2 g. Still no reduction in voltage.

    We double-checked the accuracy of the True meter with a new meter. There is 124v coming out of the receptacle, which is within normal range.

    What else can we do? Is a 150 w transformer less precise at reducing voltage than a 300 w?

    Are you testing the voltage with a load or without the load on?
    They say I shot a man named Gray and took his wife to Italy
    She inherited a million bucks and when she died it came to me
    I can't help it if I'm lucky


      Landscape lighting often uses a transformer voltage higher than 12.00, and automotive 12V bulbs are really specified for 13.6 volts or higher, since the battery may be on charge.
      A Malibu (TM) system will specify a minimum length of a maximum wire gauge between the transformer and the closest incandescent lamp to avoid just the kind of problem you are seeing.
      When dealing with "12 volt" it is a good idea to confirm that all of the components are on the same page with respect to actual design voltage.

      A back to back parallel pair of power or zener diodes in series with one lead may solve your problem.

      Sent from my XT1080 using Tapatalk
      Last edited by GoldDigger; 01-21-14, 03:30 PM.