BRUSH SPARK MONITORING DEVICE FOR SYNCHRONOUS MACHINE

PURPOSE:To easily and surely perform a diagnosis of soundness of a brush spark monitor device itself and its adjusting test by providing a simulation signal generating device. CONSTITUTION:A pilot brush 5, for detecting voltage between current collector rings 4a, 4b and a main brush 3, is connected to the collector rings 4a, 4b, and a brush spark monitoring device 6A connects the pilot brushes 5 and the main brushes 3. The brush spark monitoring device 6A detects a change of voltage of the main brush 3 by generation of a spark through a voltage detector 7 and a signal processing circuit 8, generating an alarm by a signal comparator 10 when a signal of the detection exceeds a fixed level. A simulation signal generator circuit 13, which generates a simulation signal of each kind simulating the change of voltage of the main brush 3 due to the generation of the spark, is provided and used for a diagnosis of the spark monitoring device 6A itself and adjusting test thereof.