Rae Q-RAE, Operation And Maintenance Manual

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MAINTENANCE
7-4
7.2 Sensor Replacement
The hydrogen sulfide, carbon monoxide, combustible and
oxygen sensors all have an expected operating life. Under
normal operating condition, most sensors will lose their
original sensitivity after the expected operating life and
will need to be replaced.
Each sensor module in Q-RAE includes a non-volatile
memory, which records the manufacturing date of the
sensor. In the diagnostic mode, the microprocessor will
check the date code and display the expiration date of each
sensor. It is suggested that the user should replace the
sensor when the current date exceeds the expiration date of
a sensor. However, the sensor can be used beyond the
expiration date as long as the sensitivity is adequate for the
purposes of the measurements. Contact the service
department to determine the viablitiy of sensors that are
past expiration.
Sensor Replacement Procedure
The hydrogen sulfide, carbon monoxide, oxygen and
combustible sensors each have their own unique sensor
sockets in the Q-RAE monitor. This requires careful notice
to be paid when replacing sensors.
1.
Turn off power of the Q-RAE.
2.
Refer to Figure 7-1, open the monitor cover by
unscrewing the two captured screws from the bottom of
the monitor case.
Disconnect the battery pack.