10.3 Zero and Calibration
Because all gas sensors change their
performance characteristics over time, the
following checks are recommended:
•
Zero
Every 1 month
•
Gas response*
Every 1 month
•
Calibration
Every 6 months
Instructions on how to make zero and calibration
adjustments from the instrument keypad are in
Section 8. Refer to the manual supplied with
SetPortable
software for use of a PC to make
adjustments (see Section 12).
*Due to the safety nature of gas detection
instruments, it is recommended that sensors
are regularly gas checked. Instrument sensors
may be adversely affected by certain
environments (Section 13). A monthly test
with a known gas mixture will ensure that the
instrument responds with appropriate
indications and alarms.
10.4 Sensor Replacement
Required when instrument fails to calibrate due
to low sensor output.
Key:
1
Top moulding
2
Fixing screw
3
Gas sensor
4
Sealing ring
5
Sounder ‘O’ ring
6
Main ‘O’ rings
Figure 10.1
Issue 5
Page 23
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