Wiring RV Controller Load or not?

Jonesz
Jonesz Registered Users Posts: 18
Going to finally hookup my Morningstar 15 MPPT Sunsaver and panel. The instructions include load wiring. I am assuming I can disregard this and concern myself only with wiring the Kyocera 135 to the controller and the contoller to my batteries, correct? I was going to put an inline fuse 25 A by the battery +ve and forget about fusing the line from the panel. Seems to me I have read here that a fuse was not required on that line.
Jonesz

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,591 admin
    Re: Wiring RV Controller Load or not?

    You only need to fuse solar panels if you have 3 or more parallel strings--Then you would need one series fuse per series string.

    Or if you have such a big panel/array you exceed the maximum input rating for the controller, then you should have a fuse on the controller PV input.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Jonesz
    Jonesz Registered Users Posts: 18
    Re: Wiring RV Controller Load or not?

    Thanx Bill-So I can disregard the load wiring diagram?
    Jonesz
  • BB.
    BB. Super Moderators, Administrators Posts: 33,591 admin
    Re: Wiring RV Controller Load or not?

    Can you give me a link to the diagram you are asking about?

    Some solar charge controllers have a separate output that is called "LOAD" that can controller an external load and turn the load off (from the battery) if the battery voltage falls below 10.5 (or 11.5) volts.

    The load circuit is usually rated somewhere around 8-10 amps maximum... OK for small loads, but not very much power for an inverter (around 50 watt maximum AC inverter recommended). If you put too large of load on the terminals, you may cause the controller to fail.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • oaklandpower
    oaklandpower Registered Users Posts: 11
    Re: Wiring RV Controller Load or not?
    Jonesz wrote: »
    Thanx Bill-So I can disregard the load wiring diagram?
    Jonesz

    You can think of the "load" output as a undervoltage protected output. If you run you load direct from the batteries you can leave the load terminals on the controller unconnected. You inverter should provide undervolt protection for the batteries.
  • Jonesz
    Jonesz Registered Users Posts: 18
    Re: Wiring RV Controller Load or not?

    Thanx Oakland, couldn't find a link for Bill. Will leave the load connectors unattached. I seem to be having PC connection problems at this end and have been having trouble accessing this site and doing proper searches /downloads etc.
    Jonesz