Switch to change from Solar panel to DC power supply

I am looking for a switch. I have a solar panel that drives a 12-24V dc Pond pump. I live in a colder climate and I don't want the pond to freeze so I need to have it pump even when the solar panel isn't getting light. I don't want to use a battery. For winter I'd like to drive the pump during daylight and then when the light gets low I'd like it to switch to a 12-24V AC to DC power supply that I have to drive the pump. Ideally I'd like this to be adjustable to have this kick in based on how much light is available. Any help would be greatly appreciated.

by AndyB123
September 23, 2024
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1 Answer

Answer by tubing

maybe some pre-fab industrial electronic products might suit best to solve your problem. An (adjustable) level detector followed by a hysteresis window comparator to avoid "flickering" of your output drive during twilight. A double pole - double throw relay can switch between your power supplies.

+1 vote
by tubing
September 24, 2024

or maybe just only the relay that drops off and switches to the main source when the solar panels do not provide sufficient energy.

by tubing
September 24, 2024
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