What is the "light bulb" feature on my solar charge controller?

What is the "light bulb" feature on my solar charge controller?

The light bulb feature on most solar charge controllers are usually called "load" or something similar. Typically it is designed for lighting applications. When the controller senses a charging current from your panel, it will turn the load off. Then, when it stops sensing power from your panel, it realizes that it must be dark outside, so it turns the load on. Usually you can also set the load to be on for 24 hours if you want. Other more sophisticated charge controllers can let you define which hours you want the load on. If the load is never used (which is very common), then the charge controller will still regulate charging with no excess power produced because it will disconnect the panel when the battery is charged.

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  • Jacob

    If I set up a livestock fencer to 30 watt solar panel would I attach the fencer unit to the load terminals instead of attaching directly to the battery

  • Bob

    Hi Victor, Yes, it is 12 volts (it’s the exact same voltage as your battery voltage). It isn’t high current though and it’s limited to about 30A maximum.

  • Victor Mendoza

    Back on the load output on my mppt controller. Is it 12 volts output with high current? It’s the 100 amp that came on my cutting edge power..

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