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65-2661RK-03-04 M2A Transmitter Operator’s Manual
Chapter 7: Maintenance
Overview
This chapter describes procedures for performing preventive maintenance,
troubleshooting, calibrating the M2A, and replacing field replaceable parts.
Preventive Maintenance
This section describes a recommended preventive maintenance schedule to ensure the
optimum performance of the M2A. It includes daily, monthly, and biannual procedures.
Daily
Verify a display reading at the controller of the background concentration of CO
2
. Typical
background concentrations of CO
2
vary from about 300 to 600 ppm (0.03 to 0.06 %volume)
depending on location.
Monthly
This procedure describes a test to verify that the M2A responds properly to the target gas.
NOTE:
Performing a response test on the M2A may cause alarms. If you do not want
external alarms to actuate, disable any external alarms during the response test
to avoid unwanted external alarm indications.
NOTE:
The following procedure assumes the use of a calibration kit which includes a
calibration gas cylinder and a fixed flow regulator with an on/off knob.
1.
Disable all external alarms if external alarm indications are not desired during the
response test.
2.
Screw the calibration gas cylinder into the fixed flow regulator.
3.
Use the flexible tubing coming from the calibration adapter/splash guard to connect
the regulator to the calibration adapter/splash guard.
4.
Turn the regulator knob counterclockwise to open the regulator.
5.
Allow calibration gas to flow for the length of time determined in “Determining
Response Time” on page 32.
6.
Verify that the display reading is within ± 20% of the gas concentration.
NOTE:
If the reading is not within ± 20% of the gas concentration, calibrate the M2A as
described in “Calibration” on page 33.
7.
Turn the regulator knob clockwise to close the regulator.
8.
Unscrew the calibration gas cylinder from the fixed flow regulator.
9.
Disconnect the calibration adapter/splash guard’s flexible tubing from the regulator.
