I'm having a few issues on site where the client has to stand under the PIR's and wave their hands around (flashbacks to Team America) to trigger the load on. I have confirmed that the voltages are correct (28v+) and that the trim pots are set so that the sensor will operate in any lighting condition. It seems to be an issue site wide over different networks so it may just be faulty sensors in this case but I was wondering if anyone else has come across this. All sensors are the 360 type flushed into the ceiling.