MAS
MAS K05/0722
page 13
11. Maintenance
Sensor cleaning and Inspection
Your MAS essentially requires no maintenance and has no regular maintenance
schedule, other than periodic flow path cleaning if the gas is dirty. Calibrations
may be scheduled once or twice yearly, depending on the accuracy to be
maintained, or as needed.
It is recommended that your MAS be returned to Kobold Messring if cleaning,
repair, or recalibration are necessary. This is usually your most cost-effective and
reliable alternative.
Attention! If you wish to clean your MAS purge it with a neutral
gas (e.g. nitrogen) thoroughly before disconnection from the gas
line when toxic or corrosive gases have been measured. Never
return an MAS to KOBOLD Messring or any other repair or
calibration facility without fully neutralising any toxic gases
trapped inside.
Note: A cleaning, described as follows, is only possible with
instruments made out of stainless steel (MAS-3xxx and MAS-
4xxx)
Cleaning is accomplished by simply rodding out the sensor with the Sensor
Cleaning Stylette, available from Kobold Messring for this purpose. (A 0.020 inch
to 0.028 inch diameter piano wire may also be used.) During maintenance and
cleaning please observe the following steps:
1. Remove the unit from the system.
2. Remove the two socket head access port plugs with a 6mm (¼ inch) allen
wrench.
3. Visually inspect the sensing ports and sensor concerning dirt and corrosion.
4. Use a hemostat or tweezers to push the cleaning wire into the downstream
opening of the sensor tube. Do not force the cleaning wire; move it back and
forth –
Do not twist or rotate
.
5. Flush the sensor tube with a non-residuous solvent. In cases where solids are
deposited on the sensor and can not be removed, units should be returned to
factory for complete cleaning and re-calibration.
6. Blow dry all parts with dry nitrogen and re-assemble the unit.
7. When the transducer is re-installed in the system, leak test the connections.
Do not use a liquid leak-search medium, instead watch the possible arising
pressure loss in your system.
8. Check transducer calibration.
