Thread: Motion sensor to switch relay

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Hi all! This is not my first build, but this is my first forum and first ever post online and so i hope someone out there will be able to help me.

I bought a simple 120vac motion sensor that is used to turn on a light when it detects motion (Leviton PR150) and it funtions correctly when installed in place of a wall switch, however it doesn't seem to work correctly when I install a 120vac DPDT relay (Radio Shack: Part Number 275-271) on the load end. I can't seem to figure out why but it turns the relay on, and the volage reads 113v, but when the timer runs out on the motion sensor, the voltage increases to 130v when it should be 0 volts. Instead of de-energizing the relay, it stays energized.

I hope someone will be able to figure this out. Is it the motion sensor or the relay that is not functioning correctly?

Thank you for your help!!!!

Is it possible that the PIR has a min watt load rating and the relay isn't drawing enough of a load that it doesn't behave correctly. I've seen this on several Home Automation module relays that if there isn't enough wattage on the load, the device turns on but never turns off.

Try adding a 40watt light bulb on the PIR load along with the relay to see if with the increased wattage load if the relay & light turn off when the timer runs out.