Sensor diagnostic apparatus and method thereof

摘要

A sensor failure and detection apparatus and method for use in a redundant sensor system are disclosed. A control circuit disconnects reference power (5) supplied to a sensor (4) and then monitors the voltage decay output by the sensor. The monitored rate of voltage decay of the sensor is compared to the expected natural voltage decay of the sensor to detect failures caused by short or open circuits. An error counter keeps track of the number of failures. Alter a threshold number of times in which the monitored voltage decay does not compare to a predicted rate of decay, power to the sensor is removed and the sensor is isolated from the system. <IMAGE>