Interruption detector

Abstract

Interruption detector (1, 20) with: - several power supply circuits (6a, 6b) which supply a constant current from a DC power supply (VC) via resistive elements (7a, 7b) to several loads (3a, 3b), wherein the resistive elements (7a, 7b) each have a predetermined resistance value; - several voltage detectors (8a, 8b) which are each arranged on the several power supply circuits (6a, 6b) and each detect a voltage of a corresponding resistive element (7a, 7b) on a load side; and- a control circuit (5) which, for each of the multiple power supply circuits (6a, 6b), determines an interruption state of a power supply path to a corresponding one of the multiple loads (3a, 3b) on the basis of voltages detected by the multiple voltage detectors (8a, 8b), wherein- the control circuit (5) initial values ​​of detected voltages detected by the multiple voltage detectors (8a,8b) is detected when the multiple power supply circuits (6a, 6b) are not supplying power to the multiple loads (3a, 3b), reads and stores, - then, when one of the multiple loads (3a, 3b) is supplied with power by one of the multiple power supply circuits (6a, 6b), the control circuit (5) calculates a voltage across the terminals of one of the resistive elements (7a, 7b) that is arranged on one of the multiple power supply circuits (6a, 6b) that supplies power to one of the multiple loads (3a, 3b), based on: - a first detected voltage that is detected by one of the multiple voltage detectors (8a, 8b) that is arranged on one of the multiple power supply circuits (6a, 6b) that supplies power to one of the multiple loads (3a, 3b), - a second detected voltage that is detected by another of the multiple voltage detectors (8a, 8b) is recorded,which is arranged at another of the several power supply circuits (6a, 6b) that does not supply power to another of the several loads (3a, 3b), and- stored initial values ​​of detected voltages, and- the control circuit (5) determines that the power supply path to the one of the several loads (3a, 3b) that is supplied with power has an open-circuit state when the voltage across the terminals of one of the resistive elements (7a, 7b) is less than or equal to a threshold voltage.

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