6 maintenance, Sensor replacement – Analytical Industries GPR-2500 S Oxygen Analyzer User Manual
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6 Maintenance
Generally, cleaning the electrical contacts or replacing filter elements is the extent of the maintenance
requirements of this monitor.
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-2500S monitor. Expected sensor
life is inversely proportional to changes in oxygen concentration, pressure and temperature.
Serviceability: Except for replacing the oxygen sensor, there are no parts inside the monitor for the operator to
service. Only trained personnel with the authorization of their supervisor should conduct maintenance.
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 Integral Oxygen Sensor:
1. Remove the four (4) screws securing the top
section of the enclosure, set them aside for
reinstallation and raise the hinged top section 180º
until it locks in place.
2. Caution: Do not remove or discard the gaskets
from either the enclosure or junction box. Failure
to reinstall either gasket will void the NEMA 4
rating and RFI protection.
3. The monitors design provides protection from RFI
that is maintained by leaving specific mating areas
of the enclosure unpainted to maintain conductivity
the gasket, top and bottom sections of the
enclosure. These unpainted areas are protected by
gaskets and contribute to maintaining the NEMA 4
rating. Do not paint these areas. Painting will
negate the RFI protection.
4. Remove the oxygen sensor from the bag.
5. Screw the oxygen sensor into the threaded hole tapped in the bottom of the enclosure and finger tighten plus
one half (1/2) turn to ensure a good seal from the o-ring affixed to the sensor.
6. Remove the shorting device (looped wire) from the receptacle located at the rear of the sensor. Minimize the
time the sensor is exposed to ambient air.
7. Assure the keyway registration of the female plug on the cable and male receptacle on the sensor match up.
8. Push the female plug (including the knurled lock nut) molded to the cable into the male receptacle attached to
the new sensor.
9. Screw the knurled lock nut attached the cable onto to the male connector attached to the sensor, tighten
finger tight plus ¼ turn.