Anyone got any ideas??

Thread Starter


Joined Dec 21, 2005
I need an innovative suggestion!

Im trying to design a device which uses a motor and has a safety cut out feature.
Basically I will have a motor running and i need a remote device to cut the power to the motor when the device gets within a certain range of the motor.

Ideally the remote device will not need a power source. I was thinking that some sort of emmiter (of radio signals or something) would be connected to a circuit controlling the motor which constanly pumps out a short range signal. When this remote device gets within a meter for instance of the motor , the signal is bounces back to the circuit and power is cut to the motor via some sort of relay switch.

I hope ive explained what Im trying to do - i apologise if it sounds confusing.

Does anyone have any idea of a device which can do this?


Joined May 16, 2005
RFID systems are marketed for motor driven gates. Ranges are up to sevearal feet (a few meters) when an antenna is added to the system. Motors are as big as 1hp (750watt).