65-2660XL-XX-04 M2A-XL Transmitter
Chapter 7: Maintenance
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Determining Response Time
Since the detector junction box is installed remotely from the M2A-XL, the response time of the
detector will depend on the length of flexible tubing that is attached to the calibration adapter/
splash guard. To determine the response time based on the length of tubing connected:
1. Place the M2A-XL into its calibration mode or disable external alarms.
2. Note the current gas reading displayed at the M2A-XL.
3. Screw the regulator into the calibration cylinder. Do not use a zero air cylinder for this
operation.
4. Use the flexible tubing coming from the calibration adapter/splash guard to connect the
regulator to the calibration adapter/splash guard.
5. Turn the regulator’s on/off knob counterclockwise to open the regulator. Gas will begin to
flow. Take note of the time or start a stopwatch.
6. When you first start to notice an increase in the gas reading, note how much time passed
between starting the gas flow and noticing a reading response.
7. Turn the regulator’s on/off knob clockwise to close the regulator.
8. Unscrew the regulator from the calibration cylinder.
9. Disconnect the calibration adapter/splash guard’s flexible tubing from the regulator.
NOTE:
Do not disconnect the flexible tubing from the calibration adapter/splash
guard.
10. Add 1 minute to the length of time determined in Step 6. This is the response time for the
detector. When performing a zero adjustment or span adjustment, gas must be applied for this
length of time.
Calibration
This section describes how to calibrate the M2A-XL transmitter. It includes procedures to prepare
for calibration, enter Calibration Mode, adjust the fresh air (zero) setting, adjust the span setting,
and return to normal operation.
WARNING: The M2A-XL is not an active gas monitoring device during the calibration
procedure. The 4-20 mA output signal will “freeze” at 3.5 mA and all relays will
remain in their non-alarm state while the M2A-XL is in Calibration Mode. The
output signal will not indicate current readings and the relays will not resume
operating normally until the M2A-XL is in normal operation again.
