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Wiring two power supplies to 2 banks on 1 controller

Discussion in 'Power Supplies' started by nmiller0113, Oct 20, 2014.

  1. fasteddy

    fasteddy I have C.L.A.P Global Moderator

    Apr 26, 2010
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    Albion Park NSW
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    The reason for this is because if you tie back at the power supply then you still may not eliminate ground loops due to the different resistance paths of the cable and the string/strip which then can still cause issues, by connecting the ground at the lights you ensure you have a balanced ground at the injection point

    With controllers that have 2 banks or more like the pixlite, j1sys and Sandevices you will find that on the board itself that the ground is tied between the banks but the +V is seperated allowing you to have different voltages.
  2. OP

    nmiller0113 New Elf

    Oct 29, 2012
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    Thanks to everyone with their great info and responses. I also got an email back from Jim at SanDevices today about why he looped the AC Ground to the DC -V. Here it is just for reference:


    It is good practice and is generally advised except in certain rare cases.
    The jumper from DC- to AC ground is to protect against the possibility of
    a fault in the power supply that could provide a path between the AC line
    voltage and the DC output. This could potentially result in the presence
    of hazardous AC voltage levels being applied to the pixel controller and

    I know some folks don't agree with this practice, but it's a good idea to
    have everything referenced to a common ground. The Ethernet connection is
    isolated from ground, so the only way to insure that the pixel controller
    (-) is tied to earth ground is through the power supply.

    A question I get is why doesn't the power supply manufacturer provide the
    connection between - and ground. The answer is that some applications may
    require + to be grounded, and others, such as wiring power supplies in
    series, or when powering sensitive analog circuitry, may not allow the use
    of the ground connection.

  3. David_AVD

    David_AVD Bite my shiny metal ass! Community Project Designer Generous Elf

    Jun 12, 2010
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    Victoria Point (Brisbane)
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    Check out the ACL wiki for this kind of thing. It has diagrams of various situations. Example 2 is the one that seems to fit your case.

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