DETECTION OF AN INSULATION DEFECT

摘要

An electrical power supply device includes a DC voltage source with terminals, a controller, and an insulation-defect detecting device for detecting an insulation defect of the voltage source. The device has input terminals connected to source terminals, and circuits connected between respective input terminals and an intermediate point. The insulation-defect current-detection circuit connects between ground and the intermediate point. Both circuits have current-limiter circuits that open and close a connection between respective inputs and the intermediate point. Both current-limiter circuits are rated for traversal by a current of less than a standardized safety threshold when the first current-limiter circuit is closed and one of the terminals of the DC voltage source is shorted to ground. The control circuit is configured to simultaneously keep one current-limiter circuits open and the other closed.