Metex 2200R ORP Analyzer/Controller - Manual (Page 17)

Model 2200R Page 15
5.4 Analog Output Range Expand
3.5.1 To increase the resolution of the analog outputs, the range may spread over any
section of the scale. as long as is spans at least 10% of full scale. The best way to
describe this setup is by example. Suppose you wish the outputs to span from
200mV to 600mV. Proceed as follows:
a) Enter the menu by pressing CALL until the OUTPUT HIGH LED is illuminated.
Use the arrows keys to make the display read 600. Press ENTER. The display
will flash until ENTER is pressed again to confirm the value.
b) Press CALL and the OUTPUT LOW LED will illuminate. Use the arrow keys to
make the display read 200. Press ENTER. The display will flash until ENTER is
pressed again to confirm the value.
c) The analog outputs will now be at 0% when the ORP is 200mV, and will
increase to 100% when the ORP of the solution is 600mV.
d) Press RUN to place the instrument on line, or press CALL for another menu
selection.
NOTE: A range expand of less than 10% of full scale is an invalid entry which will
be indicated by the LED flashing when you return to RUN. To correct,
return to the menu and correct the output settings.
5.5 Control Relay A Setpoint
3.5.1 The Control Relays are configured by programming the Setpoint and Deadband.
•Setpoint: is the value at which the relay will energize
•The Deadband: is the value at which the relay will de-energize
As shipped from the factory, Control Relay A, is configured to control decreasing
ORP. However, you may change the direction of the relay by changing the position
of the DIP switch. (Refer to Section 4.7)
3.5.2 The relay setpoint may be set at any point on the scale.
To program the setpoint. Proceed as follows:
c) Enter the menu by pressing CALL, proceed by pressing Call until the RELAY A
SETPOINT LED is illuminated. Now use the arrow keys to make the display
read the desired value. Press ENTER. The display will flash until ENTER is
pressed again to confirm the value.
d) Press RUN, to place the instrument on line, or press CALL for another menu
selection.
5.6 Control Relay A Deadband
5.6.1
If you have configured the relay to control decreasing ORP, the deadband will be
higher than the setpoint. i.e. the auxiliary device connected to the relay will increase
the ORP. If you have configured the instrument to control increasing ORP, the
deadband will be lower than the setpoint. i.e. the auxiliary device connected to the
relay will decrease the ORP.