controller?

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jchamp
jchamp Registered Users Posts: 22
I would like to hook up my controller to my batterys today, I will be running the wire about 5 ft. what size wire will I need? Also how much energy will I lose by leaving a 1200w inverter on in the battery box? or what size wire do I need to run it about 4ft. into the house? Thanks from a newbe.

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  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
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    Re: controller?

    You must provide more detail! We don't know anything about your system and therefore can't make any real suggestion.

    You may have posted some relevant information somewhere else, but if it is not in the thread where you are asking the question we don't know!

    Battery size, controller model, inverter model, expected loads etc.

    Icarus
  • jchamp
    jchamp Registered Users Posts: 22
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    Re: controller?

    I have 2 d/c batterys 115a/h the controller is 10a I received with the 2 / 45w kits I got at harbor frieght. I want to run a32 inch tv with a receiver.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,443 admin
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    Re: controller?

    You can look at cables here. You probably need 2/0 cables if you want to use your inverter's full power.

    You should not put the inverter into the battery box for several reasons:
    • Need ventilation. The inverter at full power will output ~150 watts of waste heat.
    • Non-sealed batteries can vent sulfuric acid when charging--damaging to electronics.
    • Batteries when charging (and over-charged sealed batteries) will vent hydrogen and oxygen gas--explosive around sparks.
    • Need access to inverter to turn on/off--don't want switch in explosive atmosphere.
    If your question was how much power will you waste if you just leave the inverter turned on when not used (even if the TV/Sat Receiver are turned off)?

    Several answers here... The "typical" AC inverter will run about 8 watts with no load... So 8watts*24hours=192watt*hours. Or about as much energy as your two 45 watt panels will collect on an average sunny day.

    The other part of the question--is how much power does your TV and Sat Receiver (guessing) consume when turned off...

    The TV, depending on age may draw from 1 to 10 watts when "off" (need power for remote control receiver and to keep the picture tube hot for "instant on").

    For Satellite Receivers (and some HDTV and cable receivers), they may draw about as much power when turned on as when "off"--which can easily be 30 watts. They keep the electronics running to update firmware, billing, and channel guides.

    Using a Kill-A-Watt meter is real handy to find these "phantom" loads. Most times, it is worth placing all of your home A/V gear on switched outlets. At worst, you may have to wait a few minutes for the guides to update. Obviously, DVRs and VCRs need to be left plugged for timed recording (and the "boxes" too--if needed).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • jchamp
    jchamp Registered Users Posts: 22
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    Re: controller?

    thanks a lot for the info on my inverter wiring Bill. what about the wire going from the back of my controller to the battery box? what size do i need? i'm running about 5ft. thanks again.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,443 admin
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    Re: controller?

    The controller wiring is not near as large... You have a 10 amp controller and a short distance--even 14 awg house wiring (good for 15-20 amps) will work fine (keep controller to battery leads as short as practicable and the controller should be the "same temperature" as the batteries--if temperature compensated). This will help ensure that the controller measures the "correct" battery voltage and battery temperature (for best battery charging).

    If you need to add wire length--add it between the solar panels and the controller.

    If the wire is exposed to the sun, then you need outdoor rated wiring (and/or metal conduit) to prevent the UV from damaging the insulation.

    You can use the Wiring Calculator to see exactly what awg of wire you need vs the run and current (longer wire needs heavier wire to reduce voltage drop and power loss).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • jchamp
    jchamp Registered Users Posts: 22
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    Re: controller?

    Just want to say many thanks Bill. James;