Omega Engineering Dissolved Oxygen System Oxygen Equipment User Manual


 
Page 19
7.3 Temperature Output
7.3.1 The 0-5 Vdc and 0-1 mA outputs may be programmed to track the temperature of
the process. The factory outputs have a linear range corresponding to 0°C to 40°C,
(or 32°F to 104°F.) Suppose you wish the output to span 10°C to 45°C. Proceed
as follows:
a) Enter the Utility Menu as described in 7.2.1.
b) Press CALL to indicate OUTPUT HIGH, which is the “Temperature output,
100% point” in the Utility Menu. (See table in 7.2.2). Now use the arrow button
to show 45.0 on the display. Press ENTER. The display will flash until ENTER
is pressed again to confirm entry.
c) Press CALL to indicate OUTPUT LOW, which is the “Temperature output, 0%,
point” in the Utility Menu. (See table in 7.2.2). Now use the arrow buttons to
show 10.0 on the display. Press ENTER twice as above.
d) Press RUN to return to on line or press CALL to proceed to another item in the
Utility Menu.
7.4 Adjust 0-1 mA / 0-5 Vdc Output
7.4.1 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 (DVM). Proceed as
follows ignoring the instrument display:
a) Turn off the power to the instrument. Connect your DVM 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 “%sat/ppm”, 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
DVM read 1.25V. Press ENTER twice to confirm.
d) Press CALL to indicate TEST, 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 DVM
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
7.5.1 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 Multimeter (DVM). Proceed as
follows ignoring the instrument display.
a) Turn off the power to the instrument. Connect your DVM to the 4-20 mA output
terminals on the power supply board.