cameronjames@snoc01.enet.dec.com (James Cameron) (04/26/91)
I'd like to monitor the performance of some of my major appliances, such as refridgerator and hot water heater, without opening them or altering them in any way. I'd use a microcomputer for the logging. I guess I can wrap a coil of wire around one of the conductors; then measure the induced voltage. But how many turns do I need and what sort of safe digital output can I have? Can I hook it into an optocoupler in order to avoid damage by spikes? Are there devices on the market to do this? Replies by mail welcome. (I'm on 240V AC in this country...) -- James Cameron Digital Equipment Corporation (Australia) P/L (cameronjames@snoc01.enet.dec.com)