Author Topic: Reversing Controller Switching.  (Read 1028 times)

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Reversing Controller Switching.
« on: May 18, 2017, 02:25:26 AM »

I have a mental block on something really simple I need help with.

I have a bunch of light sensative switches that normally turn on a light when it gets dark and turn it off again when it gets light.
I want to use them on my hydroponic system to switch the pump OFF at night and back on during the DAY.  I need to reverse the 12 Switch output to do this. I know it can be done simply with a transistor or a relay but for the life Of me, I can't remember how I have done it before.   :-[

Any help or suggestions would be appreciated.

This is the controller/ switch I have.


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Re: Reversing Controller Switching.
« Reply #1 on: May 18, 2017, 03:18:31 AM »
You need a relay with a Normally Closed (N.C.) connection point connected to the pump. When the relay are energized from the light controller (at dusk), the N.C. point opens, and stops the pump. :)

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