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Hello, I have a motion detector that is normally closed and opens when you trip it, how do I reverse this?

the motion detector is a plain security one (without a light)

IMG_0592.JPG
4 answers
Mar 7, 2009. 5:02 AM11010010110 says:
if there is unused 5th entry in the relay its probably NO. try connecting your circuit to NO and C
Mar 6, 2009. 9:31 PMkelseymh says:
Your blurry picture (yes, I know you're working on it :-) implies that the output is only NC. Is that really true? Often such circuits have both an NC and an NO output (i.e., the two opposite poles of a relay), for flexibility.

NO (as I'm sure you know) has the downside that it is an energy waster :-( If you can modify the system you want to control, you might want to consider redesigning it so that NC is the right approach (it draws zero current until tripped, then becomes activated).

If you're hooking into an existing system, then you can convert NC to NO with a relay in series.
Mar 6, 2009. 9:04 PMDefault117 says:
That's a little hard to say without a detailed picture and/or schematics. What do you wish to accomplish?

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