65-2662XL-04 M2A-XL Transmitter
Chapter 7: Maintenance
•
39
Calibration Frequency
Although there is no particular calibration frequency that is correct for all applications, a
calibration frequency of every 3 to 6 months is adequate for most hydrogen sulfide transmitter
applications. Unless experience in a particular application dictates otherwise, RKI Instruments,
Inc. recommends a calibration frequency of every 3 months.
If an application is not very demanding, for example detection in a clean, temperature controlled
environment where hydrogen sulfide is not normally present and calibration adjustments are
minimal at calibration, then a calibration frequency of every 6 months is adequate.
If an application is very demanding, for example if hydrogen sulfide is present often and in
significant concentrations or the environment is not well controlled, then more frequent
calibration than every 3 months may be necessary.
Slow or No
Response/
Difficult or
Unable to
Calibrate
• Unable to
successfully set the
fresh air or span
reading during
calibration.
• M2A-XL requires
frequent
calibration.
NOTE:
See
“Calibration
Frequency” on
page 39 for
calibration frequency
guidelines.
• The calibration
cylinder is low, out-
dated, or defective.
• The calibration gas
flow rate is too low.
• The calibration gas is
not an appropriate
concentration.
• The detector is
malfunctioning.
• The terminal PCB is
malfunctioning.
• The flexible tubing
to the calibration
adapter/splash guard
has become kinked,
blocked, or
disconnected.
1. Verify that the calibration
cylinder contains an adequate
supply of a fresh test sample.
2. Verify that the regulator used for
calibration is a 0.5 LPM
regulator.
3. Verify that the calibration gas
concentration is appropriate for
the transmitter. The concentration
should be in the detection range,
preferably about half of the
detection range.
4. Verify that the flexible tubing to
the calibration adapter/splash
guard is clear and connected to
the calibration adapter/splash
guard.
5. If the calibration/response
difficulties continue, replace the
detector.
6. If the calibration/response
difficulties continue, contact RKI
for further instruction.
Table 7: Troubleshooting the Carbon Monoxide Detector (Continued)
Condition
Symptom(s)
Probable Causes
Recommended Action
