Help with Cable Sizing and Fuses

  • Good afternoon,

    I am pretty new to the world of solar pv etc...and I am currently in the process of designing a system for our community allotment to provide power which will allow us to pump water from water collection tanks to other tanks on the allotment.

    I am hoping that if I breakdown what I know, someone can help me with what I don't know.


    2x Solar Panels, mounted in series.

    Each Panel: 260W, Vmpp 30.7V, Impp 8.50A, VoC 37.8V Isc 9.01A, Maximum System Voltage 600V, Maximum Series Fuse 15A

    These will feed into my 60A EcoWorthy MPPT Charge Controler:
    60A 12/24/36/48V MPPT OLED Display Solar Charge Controller Regulator | ECO-WORTHY – eco-worthy-uk

    This will charge a battery bank made up of 1x 170Ah and 1x 90Ah Powersafe SBS Batteries (couldn't get the same Ah unfortunately) which I intend to parralel up.

    The water pump is a 12V, 260W pump.


    The complication is that the solar panels will be sighted near our polytunnel and the pump will be sighted some 50metres away. I was looking at cables etc..until someone suggested that I could have an isolator on the feed coming from the solar panels, followed by an anderson connector to disconnect the panels from the charge controller easily and safely. If I was then to mount the batteries and charge controler on a little trolley, it could juct be rolled down to the pump where a different sized Anderson Connector would allow me to plug the pump into the load of the charge controler to power the pump.


    I would be really grateful for input as I am struggling with the following:

    1. Cable sizes I need to go from the MC4 connectors off my panels to the charge controller. (distance will be no more than 12ft) (I did this caculation Isc x 1.25 x 1.25 = 14Amp which means a 14AWG cable)

    2. Cable gauge to use to parallel up my batteries (they come with M6 terminals) - not sure how to calculate

    3. Cable gauge to run from the charge controller to the pump (I did this calcuation 260w/12v = 22A meaning the 14AWG cable would also work for this part)

    4. Where I should consider fuses, and which kind and what size

    Any other considerations also greatly appreciated. As Eco-worthy only sell some of the bits I need any suggestions (UK) of where I can pick them up would be appreciated.

    Many thanks


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