Urgent advise needed on solar wires

Discussion in 'Tech/Mech General' started by UK Pete, Mar 30, 2015.

  1. UK Pete

    UK Pete Read Only Funster

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    I am pulling out the 4mm wires to my controller and running 6mm wire in its place, this is to cope with the new solar panels there are 3 in parallel giving a total of 280w, the two new ones are 2x 80w, with skinny 3mm tails the old existing one is 120w with 4mm tails, but is permanently fixed so i cant change the tails on that
    My question is i was going to link my two new panels together using the short cable that comes fitted to the panels theses cables are all pre wired with connectors, so i was going to link them then the main run from roof to controller will be in 6mm, however the short wiring that comes attached to the panels is very skinny probably only 3mm,
    Is it ok to keep the short wiring , linking the panels and have the main run in 6mm, i am doing this right now and need some quick answers thanks in advance pete
     
  2. Lenny HB

    Lenny HB Funster

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    The thinner short wiring on the panels should be fine, it is when you have long cable runs you need larger cables as the resistance therefore volt drop increases with length.
     
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  3. mitzimad

    mitzimad Funster

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    keep the small cables as short as possible
     
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  4. Moodybrook

    Moodybrook Funster

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    Can you not disconnect the existing wires from the wee black box that should be on the back of your panels ? I would then get some more connectors.

    Then there would be no restrictions on your pipeline to the controller. :)

    Maybe splitting hairs but I seem to always take the expensive route. o_O
     
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  5. Bluestar

    Bluestar Funster

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    Yes if your running in parallel the current is divided between the three sets of wiring so the main drop is on the single twin down wires so as said keep the wires going to the joint,(I guess your using a box to connect together) then run the uprated cable to the controller/ batteries keeping the run as short as possible.
     
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  6. ivorantony

    ivorantony Funster

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    Just done mine fitted a additional 100w panel and replaced all the wiring with 6 mm, it meant cutting the 4 mm pig tails from the three panels and running 6 mm all the way, but it's a simple job, make sure you cover your panels before connecting to the controller and battery,
     
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