Condition monitoring system responsive to different input pulses

摘要

In a condition monitoring system (1) for controlling a power supply in a vehicle, a charge / discharge circuit (13) includes a capacitor (C31) which discharges in response to each of the speed pulses of a speed sensor (3) and also in response to periodic pulses Microcomputer (5) is discharged. If none of the pulses are generated due to an abnormality, the capacitor (C31) is charged continuously without discharging. When the charging voltage of the capacitor (C31) reaches a switching voltage (Vx), a relay (8) is turned off to thereby cut off the power supply to various portions or parts in the vehicle. The charge / discharge circuit (13) is used in common to check the generation of the velocity pulses and the periodic pulses by adjusting the switching voltage (Vx) in accordance with a possible maximum time interval of the velocity pulses.