Oxygen Equipment User Manual

Page 17
5.12 Alarm High
5.12.1 The instrument is fitted with a relay, which is set to activate on both high and low
alarm conditions. The deadband is factory set. To set the ALARM HIGH proceed
as follows.
a) Enter the menu and press CALL until ALARM HIGH is indicated. With the
arrow buttons make the display read the desired alarm value. Press ENTER.
The display will flash until ENTER is pressed again to confirm the entry.
b) Press RUN to place the instrument on line, or press CALL, for another menu
selection.
5.13 Alarm Low
5.13.1 a) Press CALL until ALARM LOW is indicated. With the arrows make the meter
read the desired value. Press ENTER. The display will flash until ENTER is
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.