Apparatus for monitoring a device powered by the apparatus, and a method for monitoring a device from its power draw

摘要

An apparatus for monitoring a device (such as a solenoid) powered by the apparatus includes a power supply for providing an alternating power signal to the device and a monitoring circuit that measures a prescribed characteristic of the alternating power signal. A control circuit is responsive to measurements from the monitoring circuit and is arranged to analyze the measurements to determine the status of the device therefrom.