Creating a PV array ground fault

Discussion in 'The Projects Forum' started by TK421, Oct 9, 2010.

  1. TK421

    Thread Starter New Member

    Oct 9, 2010
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    Hello everyone. I would ideas on how to safely induce a ground fault in a PV array. I have 4 modules that will be connected in series in a classroom. I would like to install a device between 2 modules that will safely create a ground fault, ie. bond that conductor to ground.

    In a real world scenario, this ground fault could be caused by many things, most common source are squirrels chewing ont he wires. The wire then touches the frame of the PV array and the current increases in the circuit thereby blowing a 1A GFDI fuse in the inverter.

    Basically, I need the residual current in the conductor which is usually below 100mA to increase to over 1 amp. I understand that the resistance needs to decrease for this to happen because of Ohm's Law (I = E / R). This is accomplished in a real array by bonding the conductor to ground.

    Anyone know of a switch or similar device that can accomplish this? Many thanks!
     
  2. wayneh

    Expert

    Sep 9, 2010
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    Why not just a standard light switch or automotive toggle switch? They can certainly handle that low current.
     
  3. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
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    A light switch would do the trick.. A relay would do it "remotely".
     
  4. windoze killa

    AAC Fanatic!

    Feb 23, 2006
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    Sorry to say that could never happen in a REAL WORLD senario........

    We don't have squirrels in Australia (read "The Real World"). :D:D:D
     
  5. TK421

    Thread Starter New Member

    Oct 9, 2010
    2
    0
    Thank you for the replies, however a simple switch will not increase the current in the circuit, which is what I need to happen in this PV array. An open switch will break the path, but I need to bond that path to ground- safely!

    My apologies windoze- squirrels are the #1 cause of PV array ground faults here in California. Do tamars ever make it on the roofs down there? :D
     
  6. windoze killa

    AAC Fanatic!

    Feb 23, 2006
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    Ok. Got me confused..... Tamar?????? What is ne of these?

    About the only thing we get on our roofs is possums of various varieties. Brush tail, ring tail and what seems to be the ones that frequent my roof are the Baby Bloody Elephant Possum.
     
  7. wayneh

    Expert

    Sep 9, 2010
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    Why can't a switch "bond that path to ground"? How is a switch different than an unexpected short to ground caused by a varmint?

    I suggest a drawing.
     
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