Low Voltage Transformer Trouble

Discussion in 'Landscape Lighting' started by jimmy1111, Jan 19, 2009.

  1. jimmy1111

    jimmy1111 LawnSite Member
    Messages: 56

    Ok here are the readings for the 2 tests that I promised to get. Now we have 3 tests done by me and one test by Venture - above - for VD in Loop Runs.

    Please note that my last fixture on Circuit 3 is a medium base 50W in a light post...so I had to take the bulb out to take the readings....so the loads shown under circuit 3 already excluded this 50 W load ONLY when taking the 2 voltage readings at that fixture. I put that light bulb back to take all other readings shown in this table. (i.e. Circuit 3 bak-up to 275W for Test 1 and 235W for Test 2)

    For circuit 2 the last fixture has 20W MR16....so I was able to get the readings at the pins without taking the light bulb out.

    In summary; as I said earlier it seems the explanation of the resulting low VD Looping 12/2, which seems to equate single 8/2 wires, is that 12/2 cable has 65 strands of cooper and 8/2 cable has 133 strands of cooper...so looping 12/2 is actually using 2x65 = 130 strand of cooper which is almost the same - if not exactly the same - as using single 8/2 wires with 133 strand of cooper to that same load.

    Attached Files:

  2. jimmy1111

    jimmy1111 LawnSite Member
    Messages: 56

    awfully quiet...I guess no more criticism left for this DYI's ???:hammerhead:
  3. jimmy1111

    jimmy1111 LawnSite Member
    Messages: 56

    Here is another version of the 2 test readings in .jpg for those who can't read a .pdf file.

    Again the point of the Loop run is NOT to run 2 cables in the same trench to a fixture but to pick-up some light fixtures on one leg out of the Transformer then some other light fixtures on the second leg back to the Transformer specially when the location of the light fixtures resemble to a circular or oval shape.

    This is instead of running 2 single runs of lower gage cable (i.e. 8AWG instead of 12 AWG which is more $$$) to these 2 sets of fixtures and stopping short of connecting the last 2 fixtures (i.e. 10 or 15 ft of 12 AWG) together to make a Loop.

    VISTA - MT900.jpg
  4. jimmy1111

    jimmy1111 LawnSite Member
    Messages: 56

    I guess I graduated !!!:cool2:
  5. TXNSLighting

    TXNSLighting LawnSite Fanatic
    from DFW, TX
    Messages: 6,464

    yeh thats it...
  6. jimmy1111

    jimmy1111 LawnSite Member
    Messages: 56


    You are invited to the Loop Runs Graduation Party ......eventhough I know what you did to this thread:laugh:
  7. Go Halogen

    Go Halogen LawnSite Member
    Messages: 102

    Insanity.....I have not been here for a while and I see that the forum still attracts too many weekend warriors that are trying to save a buck.

    Jimmy, where did you come from? You need proper education.
    Also, you took advantage of that Philly distributor. You are lucky that he took back your old transformer....once you mess with product the warranty is void.

    Crazy stuff.....

    - Andy (Go Halogen)
  8. jimmy1111

    jimmy1111 LawnSite Member
    Messages: 56

    Well...the 12 AWG wire that i found fried inside is truly caused by Manufacturer defects for 2 reasons:
    1. Like everyone said here bad conections have created the fire hazard condition inside the Trans....that is a safety issue that the Manufacturer avoided a law suit by replacing my Trans....eventhough I had to pay the $100 to the distributor.

    2. 12AWG wire should never been installed inside the Trans. for each of the 300W ciurcuits when they are protected by 25 amp breakers. In this case the 12AWG wire which is rated at 20 amp was protecting the breaker and not the other way arround where it should have been. 10AWG which is rated at 30 amp should have been installed not the 12 AWG.

    As soon as I said the above 2 fatal flaws to the Manufacturer they got stunned and offer me the replacement. Maybe that's why they have discontinued the older Model.

    As far as proper eduction....thanks for some of the guys here.
  9. jimmy1111

    jimmy1111 LawnSite Member
    Messages: 56

    i'm glad that i didn't go with spider web the runs all over the yard using hubs. I just got an irrigation system installed. not one run got hit.

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