Schematics for above question...

What is it your trying to accomplish? If both need to detect movement at the same time to cause a trigger action then you would wire it in serial fashion. If they are to work independent then it would be parallel. But the fist task of any type of circut is to acomplish the goal as intended.

Motion detectors are basically switches. If you keep that in mind you can wire them exactly like you would a switch. The only caveat is that you need a neutral to make them work.

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