I think I know what is going on, but I though I'd look for insight anyway.
I have a MS16A Motion Sensor near a room door to sense entry to turn on a light. Later I added a MS10A Security Motion Sensor near (but not next to) the MS16A. The MS10A is for the security alarm, and the MS16A is for the light.
Well, the light socket-rocket fried a while back, so I never had both these working at the same time. I got around to fixing things recently, and found the light operation is intermittent.
I figure the MS10A and MS16A are stepping on each other RF-wise. BTW, the receiver for the MS10A is a DS7000, and the receiver for the MS16A is a WGL V572, so the "listeners" are different, but if both sensors "talk" at the same time, the RF gets corrupted. This does assume they are both on the same frequency.
I could move the MS10A away from the MS16A, but I want the alarm to trip upon entry into the room. But I also want the light to go on upon entry into the room. Hmmm ... sounds like a conflict.
I thought about mapping the MS10A through the WGL V572 to control the light, but the MS10A's don't seem to "catch" motion as well as the MS16A's.
Any thoughts on this?