Is there an exterior motion detector that turns power off instead of on when someone enters a space? All internet inquiries have only found power on detectors. I've also found "light curtains" but they are overkill and too pricey.

  • Seems counterintuitive. What is the use? – user56530 Feb 24 '17 at 5:53
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    You can use a relay to achieve this with any detector. – Tyson Feb 24 '17 at 13:20
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    Product recommendations are off topic Rewording to how can I make a motion detector turn off the lights with a relay would be ok. – Ed Beal Feb 24 '17 at 14:02
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    @HebrewHammer maybe he's watching something on his computer and wants to kill the screen if someone wanders by :-) – Carl Witthoft Feb 24 '17 at 14:20
  • @EdBeal I think it's worded alright - he asks if there exists a product, not for specific recommendations. I'd also like to buy something but am not sure how to search for one. I need one so my indoor grow lights will turn off when my cat wanders in to munch on grass - the lights are really bright... – Brian Burns Jun 27 '17 at 16:29

This is pretty easy with a relay:

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Just be sure to size the relay appropriately for your load (I used a light but it could be anything).

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