Metex 2200D/P91 Dissolved Oxygen Controller/Analyzer - Manual (Page 18)

Model 2200D/P91 Page 16
c) Press CALL the required number of times until RELAY A SETPOINT is
indicated. Now use the arrows to make the display read the desired value.
Press ENTER. The display will flash until ENTER is pressed again to confirm
entry. A LED above the display indicates when Relay A is activated.
d) Press RUN to place the instrument on line or press CALL for another menu
selection.
5.9 Relay A Deadband (For Model 2200D-X-2 only)
5.9.1 If you have configured the instrument with the DIP switch on the back of the panel
for falling D.O. you will wish to have the deadband (sometimes called “hysteresis”)
at a higher value than the setpoint. If you have established a setpoint of 3 ppm you
may wish the deadband to be between 6 ppm and 3 ppm. Proceed as follows:
a) Enter the menu and press CALL the required number of times to indicate
RELAY A DEADBAND. Use the arrow buttons to make the display read the
desired value (in this example, 6). Press ENTER. The display will flash until
ENTER is pressed again to confirm the entry.
b) In this example, after the instrument has been returned to RUN, the relay will be
energized when the D.O. falls to 3 ppm and will remain energized until the
reading rises above 6 ppm.
c) When Relay A is activated a LED above the display will be illuminated.
d) Press RUN to place the instrument on line or press CALL for another menu
selection.
5.10 Relay B Setpoint (For Model 2200D-X-2 only)
5.10.1 Relay B Setpoint is configured in the same way as Relay A Setpoint. See Section
5.8. A LED above the display indicates when Relay B is activated.
5.11 Relay B Deadband (For Model 2200D-X-2 only)
5.11.1 Relay B Deadband is configured in the same way as Relay A Deadband. See
Section 5.9.
NOTE: A deadband setting on the wrong side of the setpoint in an invalid entry
which will be indicated by the LED flashing when you return to RUN. To
correct return to the menu and change the deadband setting or, if the
direction of control is the problem, change the position of the relevant DIP
switch. See Sections 4.8 and 5.9.
5.12 Alarm High (For Model 2200D-X-2 only)
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.