Inventors:
Leonard J. Sheldrake - Noblesville IN
Donald O. Ruff - Anderson IN
Charles W. King - Anderson IN
Assignee:
General Motors Corporation - Detroit MI
International Classification:
H02J 714, H02P 900
Abstract:
A circuit for indicating faults in a storage battery charging system of the type including a voltage regulator controlled alternator field winding switching transistor and a rectifier circuit having a diode trio which supplies alternator field winding energizing current. A differential amplifier circuit, to which is applied normally equal reference and sensing potentials which become unbalanced with alternator faults, produces a first fault indicating signal in the event of an alternator malfunction and a transistor having the control electrode connected to the output of the field winding diode trio of the rectifier circuit produces a second fault indicating signal in the event of a failure of one of these diodes. These fault indicating signals trigger a transistor conductive to complete an energizing circuit for a fault indicating device. Additionally, an oscillator flashes the fault indicating device "on" and "off" in the event of a voltage regulator failure.