Aquametrix 2200D Dissolved Oxygen Controller/Analyzer User Manual - Manual (Page 19)

Model 2200D/P91 Page 17
pressed a second time to confirm entry.
b) Press RUN to place the instrument on line, or press CALL, for another menu
selection.
NOTE: A low alarm point higher than the high alarm point is an invalid entry, which
is indicated by the LED flashing when you return to RUN. To correct, return
to the menu and reset the alarm points.
6.0 OPERATING HINTS
6.1 Cell Care
6.1.1 If the sensor membrane is exposed to the atmosphere for more than 24 hours, the
electrolyte inside the membrane can dry out. If this occurs, the cartridge will need
to be replaced. To avoid membrane dry-out, place the sensor in a container of
clean drinking water until it can be reinstalled into the aeration basin.
6.1.2 Sensor cartridges can be stored for up to 5 years if the seal on its storage container
is not broken and the temperature is between 70°F and 80°F with 50 to 80%
humidity. Do not store sensor cartridges at temperatures below freezing point
(32°F). The electrolyte solution will crystallize at 25-30°F.
6.1.3 Cleaning the sensor membrane before each calibration is recommended. Use soft
cloth and mild soap solution to remove material from the membrane. When
cleaning, take care to avoid puncturing the sensor membrane. Should this occur,
the complete sensor cartridge must be replaced.
6.2 Calibration
6.2.1 Depending on the application, system calibration should be performed periodically
to maintain measurement accuracy. Frequent checks are suggested until the
operational history indicates the optimum period between checks.
6.3 Reset
6.3.1 The instrument can be reset without losing calibration or any of the stored values by
pressing and releasing the S9 reset button (located at the bottom of the board near
the center) This action is equivalent to turning the power off and on.
6.4 Output Hold
6.4.1 It may be useful during some system maintenance procedures to place the relay
and analog outputs on hold. To accomplish this simply press CALL. To return to on
line operation press RUN.
NOTE: To safeguard against the operator forgetting to press RUN the instrument
will automatically go back on line ten minutes after the last button was
pressed provided this feature has been enabled by placing DIP switch No.7,
Bank S1, in the ON position.
7.0 UTILITY MENU
7.1 Utility Menu Functions
7.1.1 The Utility Menu enables authorized personnel to perform the following:
• Adjust the temperature output range.
• Adjust the offset and span of the 0-1 mA/ 0-5 Vdc output
• Adjust the offset and span of the 4-20 mA output
• Perform the altitude compensation