| 摘要 |
PURPOSE:To individually detect an abnormality of each load by performing a comparatively easy processing logic for abnormality detection in the manner of providing one current detection means to the plural loads. CONSTITUTION:As the current detection means, a Hall element 2A by which a voltage corresponding to the detected magnetic field strength is generated, is connected to a feeder (RSL) between the output terminal of a 1st power supply circuit 1 in a copying machine, etc., and the plural loads 51-5n, and further an amplifier 2B incorporated with an LPF is connected thereto. In the case the rising time of the current which is detected at the time when electricity supply means 41-4n are turned on one by one, is larger than the specified amount, abnormality detection control means are provided for generating the signal. When the electricity is supplied to one of the loads 51-5n, the current in the prescribed amount is made to flow to the RSL if normal, and the prescribed rising characteristic is appeared. In the case of a solenoid or electromagnetic clutch, for example, a high peak is shown by the decreasing load and a low peak is shown by the increasing load. The respective abnormality for the loads 51-5n are detected accordingly by means of turning on the means 41-4n one by one to measure the rising time from the current of the loads 51-5n. |
