Patent ID: 6930490
Filing Date: 2005-08-16
Classification: G01R

Abstract:
1. method of detecting faults in a traction motor installation having a plurality of AC traction motors powered from a common power source, each of the traction motors being connected by associated motor cables to a cable junction and the common power source being connected to the cable junction by main cables, the method comprising the steps of: a. disconnecting a traction motor common power source from a set of main cables connected to a cable junction, the cable junction being connected to a plurality of traction motors by associated motor cables; b. Performing an initial short circuit to grind test on the traction motors through the main cables; c. performing an initial short circuit between phases test on the traction motors through the main cables; d. performing an initial leakage to ground test on the traction motors through the main cables; and e. when a fault is detected by said initial tests, performing at least one detailed test by applying a predetermined voltage to the main cables and sensing current flow in the motor cables connected-to each of the motors.