wiring size and location

loteklotek Solar Expert Posts: 65 ✭✭✭✭


I had this in the beginners corner , moved it here. I still have wires to run before I can get the insolation in, so Im hoping these problems can be resolved.
1. XW System Control Panel wiring and location. This is a remote control isn’t it?
Can/ should I locate it in the house proper? It’s wired with cat 5 cables I believe, Can I unplug it from one location and connect it in another? ( say, house to inverter )
Can I just run cat 5 wires in the walls and put ends on later or is it best to get pre-made connections?
2. Connecting panels to charge controller: what size wire do I need from combiner to the controller at a distance of 20 feet, if I have a max power of 3000W @60V DC. Can I use my combiner as a cut off switch form panels to controller or do I need one closer?

Comments

  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: wiring size and location

    for your first area of inquiry in general, i don't have any xw stuff to address it proper, but most times these things should be in an environment that will protect them from the weather and even animals and insects. prewiring presupposes an equipment placement certainty, but does make it neat afterward. this also involves wall outlets and plugs of the appropriate types.

    a voltage drop calculation is needed, http://forum.solar-electric.com/showthread.php?t=29 ,
    for your wiring questions. this depends on some known factors and the nec states that from source to load the voltage drop percentage (our primary guide to wire determination) should not exceed 5% and we agree and usually try keeping losses even lower such as 2% or 3%. the 60v may be 5 12v pvs in series to be fed, i assume, into an mppt controller to later be down converted to usually 1 of 3 standard voltages of either 12v, 24v, or 48v. this section of voltage drop percentage will need calculated by plugging in the info into the voltage drop calculator and that is wire gauge, wire total length, amps (usually the highest amps normally expected or attained like imp), and normalized voltage of operation.
    once a percentage was figured from the pvs to the controller you must do the same from the controller to the batteries and the normalized voltage may be different here than for the 60v section using mppt and the lowered voltage will shift the vdrop % higher even for the same current passing through it as in the 60v section. all sectional vdrop percentages must be added together for a final overall v drop % total that you are trying to keep under 5% for the nec and about half of that for renewables as we try to balance the high wiring costs as opposed to the high cost of pv wattage. any future expansion plans should incorporate using wires of the proper size for that future use to avoid a total rewire job.
    if you used the .xls calculator you noticed that there is provision for placing all sections into one larger overall calculation, but i prefer calculating individually myself. there is much reading in the thread, but it should not be necessary to read all in depth. take note of my comments though as some are highly pertinent.
  • loteklotek Solar Expert Posts: 65 ✭✭✭✭
    Re: wiring size and location

    Wall outlets, that sounds like a plan. a female outlet at kitchen wall, running to a female outlet in the inverter room.and a short cord with male to male plug ends that is if the remote control takes a male plug. then I can move the remote from the inverter room to the kitchen after my primary setup.

    I have designed the house with chases, walls and a room to contain all my solar gear. except for batterys. they are on the other side of the inverter wall, outside in a container, battery cables my need to be 4 or 5 ft long to reach the inverter

    after looking at the voltage drop calculator I see my 10 gauge wire should put me at under 2% from the panels to controller and 1.5% to the batterys. but maybe Ill use my extra 4 gauge from the controller to batterys if it's not to large to fit connections.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: wiring size and location

    your total will be over 3% with it at 3.5%. many try to keep the total between 2% and 3% and less is even better. most likely by how you talked of the #10 that #8 probably would be better to use, but going 3 points down to #5 (not standard) would allow for a doubling of the current for future use and #4 is added insurance to keep losses down so that sounds like something to go with even if only on the latter portion of the wiring between the cc and batteries.
    having things open or allowances made for the future is nice, but sometimes things don't always work out as we plan.
  • Dave AngeliniDave Angelini Solar Expert Posts: 6,138 ✭✭✭✭✭
    Re: wiring size and location
    lotek wrote: »


    I had this in the beginners corner , moved it here. I still have wires to run before I can get the insolation in, so Im hoping these problems can be resolved.
    1. XW System Control Panel wiring and location. This is a remote control isn’t it? Yes
    Can/ should I locate it in the house proper? Yes I like near the kitchenIt’s wired with cat 5 cables I believe, Can I unplug it from one location and connect it in another? ( say, house to inverter )Yes but since it is a network it has to be terminated at both ends correctly. In other words both the new location and it's other end will have to be connected. There are options in the manual
    Can I just run cat 5 wires in the walls and put ends on later or is it best to get pre-made connections? Yes run cat5 and connect the RJ 45 connectors later. Don't get crazy aand try to share a land line and a network on the same cat 5. Run seperate cables!
    2. Connecting panels to charge controller: what size wire do I need from combiner to the controller at a distance of 20 feet, if I have a max power of 3000W @60V DC. Can I use my combiner as a cut off switch form panels to controller or do I need one closer? At 20 feet just run #6 and you will have room for expansion. You may need a disconnect outside the structure.[/

    Good Luck with the install!
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

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