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Switch to turn OFF a circuit at dark?

Posted by albert_135 (My Page) on
Fri, Jul 10, 09 at 16:32

What keyword(s) to search for a switch to turn OFF a circuit at dark?

Spouse wants to turn off a 12volt 2amp circuit at or near darkness and turn it back on the next day.

We're having trouble finding this. Seems simple. Must be a keyword search problem.


Follow-Up Postings:

RE: Switch to turn OFF a circuit at dark?

Is this for a lawn sprinkler, etc .. ?

Would the Timer motor be powered by 12v (DC) ?
or from the 120v wall outlet ?

There are some 120v wall timers ...
electronic (programable) ON or OFF at dusk for about $ 25 ...

need to program which mode you want ..
ON at dusk OFF at dawn
ON at dusk and OFF a certain number of hours later
OFF at dusk ON at dawn
OFF at dusk and ON a certain number of hours later


RE: Switch to turn OFF a circuit at dark?

Oops. I failed to note it is a 12volt 2amp DC circuit.

It is located out in the desert so whatever turns the circuit on and off must be a solar normally closed switch or a battery.

RE: Switch to turn OFF a circuit at dark?

OK, we're getting closer ...

possibly you have a solar panel w/battery ...

and you want to turn an external circuit ON during the day ?

or to just disconnect the solar panel from the battery at night ?

RE: Switch to turn OFF a circuit at dark?

If you tell us what it is that you are trying to control you get a better answer.

RE: Switch to turn OFF a circuit at dark?

I use such a circuit for controlling an alarm system on a disconnected tool shed using Solar Cells. You can use any type of a relay to power or remove power from any circuit depending on the current capabilities of the relay. BTW, I built my circuit from schematics I got Online. It basically is a light sensor feeding a transitor switch to turn ON or OFF a relay. It has an adjustment control to set the threshold bias on the transistor for the crossover point of light and dark. Has been working for over 10 years with the Solar Cells charging batteries that feed the circuits for the alarm system.

RE: Switch to turn OFF a circuit at dark?

"keyword search problem"


No, "it's a I don't know how to do this , can you help me" probelm.

Not the "I can't or won't ask the question problem, because I can Google anything I need"

We'll help, just ask.


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