Metex 2200R ORP Analyzer/Controller - Manual (Page 24)

Model 2200R Page 22
7.4 Adjust 0-1 mA / 0-5 Vdc Output
7.6.1 It may be desirable to fine tune the 0-1 mA / 0-5 Vdc output to take into account the
characteristics of your particular loop. The following method involves a high and
low calibration and requires the use of a digital multi-meter. (DMM). Proceed as
follows ignoring the instrument display:
a) Turn off the power to the instrument. Connect your DMM to the 0-5 Vdc output
terminals on the power supply board.
b) Turn on the power. Enter the Utility Menu as described in 7.2.1.
c) Press CALL to indicate RELAY A SETPOINT which is "0-1 mA/ 0-5 Vdc output
adjust, low" in the Utility Menu (See table in 7.2.2). Use the arrow keys to make
your DMM read 1.25V. Press ENTER twice to confirm.
d) Press CALL to indicate RELAY A DEADBAND which is "0-1 mA / 0-5 Vdc
Output adjust, high" in the Utility Menu (See table in 7.2.2.) Use the arrow keys
to make your DMM read 3.75V. Press ENTER twice to confirm.
e) Press RUN to return to on line or press CALL to proceed to another item in the
Utility Menu.
7.5 Adjust 4-20 mA Output
7.7.1 It may be desirable to fine tune the 4-20 mA isolated output to take into account the
characteristics of your particular loop. Before deciding that the adjustment is
necessary, be aware of the "Output High" and "Output Low" settings you may have
programmed as described in Section 5.4. The following method involves a high and
low calibration and requires the use of a Digital Multi-meter (DMM). Proceed as
follows ignoring the instrument display.
a) Turn off the power to the instrument. Connect your DMM to the 4-20 mA output
terminals on the power supply board.
f) Turn on the power. Enter the Utility Menu as described in 7.2.1.
c) Press CALL to indicate ALARM HIGH which is "4-20 mA Output adjust, low" in
the Utility Menu (See table in 7.2.2.) Now use the arrow keys to make your
DMM read 8 mA. Press ENTER twice to confirm.
d) Press CALL to indicate ALARM LOW which is "4-20 mA Output adjust, high" in
the Utility Menu (See table in 7.2.2). Now use the arrow keys to make your
DMM read 16 mA. Press ENTER twice to confirm.
e) Press RUN to return to on line or press CALL to proceed to another item in the
Utility Menu.