Analytical Industries GPR-3500 MO Portable Oxygen Analyzer - Manual (Page 24)

Advanced Instruments Inc.
24
6 Maintenance
With exception of components related to optional equipment and charging the battery of portable analyzers, cleaning the electrical
contacts when replacing the sensor is the extent of the maintenance requirements of this analyzer as there are no serviceable parts in
the analyzer given the nature of the solid state electronics and sensor.
Serviceability: Except for replacing the oxygen sensor, there are no parts inside the portable oxygen purity analyzer for the operator
to service. Only trained personnel with the authorization of their supervisor should conduct maintenance.
Sensor Replacement
Periodically, the oxygen sensor will require replacement. The operating life is determined by a number of factors that are influenced by
the user and therefore difficult to predict. The Features & Specifications define the normal operating conditions and expected life of the
standard sensor utilized by the GPR-3500MO portable oxygen purity analyzer. Expected sensor life is inversely proportional to changes
in oxygen concentration, pressure and temperature.
Caution: DO NOT open the oxygen sensor. The sensor contains a corrosive liquid electrolyte that could be harmful if touched or
ingested, refer to the Material Safety Data Sheet contained in the Owner’s Manual. Avoid contact with any liquid or crystal type powder
in or around the sensor or sensor housing, as either could be a form of electrolyte. Leaking sensors should be disposed of in
accordance with local regulations.
Procedure:
1. Remove the four (4) screws securing the hinged front panel of the portable oxygen purity
analyzer.
2. Caution: Do not remove or discard the gaskets from the enclosure. Failure to reinstall the
gasket will void the NEMA rating.
3. Unscrew the knurled lock nut connecting the cable to the sensor.
4. Disconnect and remove the female plug (including the knurled lock nut) molded to the
cable from the male receptacle attached to the sensor.
5. Unscrew the old sensor from the threaded hole in the sensor flow housing.
6. Open the barrier bag containing the new sensor.
7. If the sensor is equipped with a shorting loop, remove the shorting wire from the pins of
the female socket attached to the new sensor.
8. Screw the new sensor, finger tight plus 1/2 turn, into the threaded hole in the flow housing
and ensure the o-ring seal is engaged.
9. Assure the keyway registration of the female plug on the cable and male receptacle on the
sensor match up.
10. Push the female plug (including the knurled lock nut) molded to the cable into the male
receptacle attached to the new sensor.
11. Screw and tighten the knurled lock nut attached the cable onto to the male connector
attached to the sensor.
12. Replace the front cover of the portable oxygen purity analyzer, replace the gasket to
maintain CE approval and NEMA 4 rating and tighten the four (4) screws to secure the
front cover.
13. Calibrate the portable oxygen purity analyzer as described in section 5.