Analytical Industries GPR-1600 MS Series PPB Oxygen Analyzer - Manual (Page 21)

Advanced Instruments Inc.
21
Temperature Controlled Heater System with Runaway Protection Circuit
The standard GPR-1600MS Series analyzer is equipped with the heater system in anticipation of very low ppm (high ppb)
oxygen analysis. However, in controlled environments or higher levels analysis the user may elect to delete the heater system.
If the analyzer is equipped with an optional temperature controlled heater system, open the front door of the analyzer to access
it. This unit is a PID controller which operates between 0-99
°F. The controller is programmed to maintain the temperature at
75-85 °F.
Caution: Do not change this setting. A higher temperature setting may drastically reduce sensor life and possibly cause
damage to the electronic circuitry of both the controller and the analyzer.
Warning:
Keep the front door securely fastened closed when the temperature controller is ON. When power is applied to the
temperature controller, the controller tunes itself to eliminate and/or minimize the over/under shoot of temperature from the set
point.
It is recommended that at initial start-up, when replacing the oxygen sensor or when trouble shooting, turn off the power to the
heater or set the temperature set point at 60
°F (to turn the heater off) to prevent overheating the analyzer.
Changing the display value from
°F to °C:
1. Push the UP ARROW and ENTER buttons down for 5 seconds to access the SECURE MENU
2. Press INDEX to advance to the F-C MENU
3. Select
°C or °F by pressing the UP ARROW key
4. Press the ENTER key when F-C starts flashing on the display
5. Press INDEX to exit the SECURE MENU
Heater Runaway Protection
Part of the optional temperature controlled heater system is a heater runaway protection circuit that protects the electronics in
the event the temperature controller should fail and thereby allowing the heater to runaway damaging the interior of the
analysis unit.
The runaway protection is provided by a J2 type device positioned between the temperature controller and the heater. This
device cuts of power to the heater if the temperature inside the analysis unit exceeds 70
°C. Should the J2 device cut power to
the heater, correct the problem and reset the runaway protector device by exposing it to 0 °C for a few minutes (a refrigerator
freezer will do).
Installing the Oxygen Sensor
The GPR-1600MS Oxygen Analyzer is equipped with an external oxygen sensor that has been
tested and calibrated by the manufacturer prior to shipment and is fully operational from the
shipping containers. The sensor has not been installed at the factory and it will be necessary
to install the sensor in the field. Caution: Review procedure before proceeding, mainly 2 and
9.
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 appendix. 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 manner similar to that of a common battery in
accordance with local regulations.
Procedure:
1. The sensor has not been installed at the factory (in standard configuration there are no
valves to isolate the sensor) and it will be necessary to install the sensor in the field.
2. As described above the following steps should already be completed:
a) Secure the sensor housing bracket with two 6/32 mounting screws, in the preferred
position the upper section with the interconnection cable should be facing the ceiling;
b) connect the gas lines;
c) electrical connections.
1. Caution: Do not change the factory settings until instructed to do in this manual.