Galvanic Applied Sciences 943-TGS-CE, Operation Manual

Page: 67 / 158

Revision 5 67 August 2021
Table 12: Analog Output Parameters
Parameter Description
None No data will be output on the analog output.
Air Demand
The Air Demand value will be output on the analog output. Scale
ranges from negative Full Scale (4 mA) to positive Full Scale
(20mA)
H2S %, SO2 %, COS %,
CS2 %
The percentage value of the H
2
S or SO
2
or COS or CS
2
concentration will be output on the analog output. Scale ranges
from 0 (4 mA) to Full Scale (20 mA)
Sigma S
The sum of the H
2
S and SO
2
concentrations, in percent, will be
output on the analog output. Scale ranges from 0 (4 mA) to Full
Scale (20 mA)
H2S/SO2 Ratio
The ratio of H
2
S concentration to SO
2
concentration will be
output on the analog output. Scale ranges from 0 (4 mA) to Full
Scale (20 mA)
H2 / Analog Output 3
The signal being input into Analog Input 3 (from a hydrogen
sensor or other measurement device that outputs an analog
signal) will be output on the analog output. Scale ranges from 0
(4 mA) to Full Scale (20 mA)
H2S ppm, SO2 ppm,
COS ppm, CS2 ppm
The parts per million value of the H
2
S or SO
2
or COS or CS
2
concentration will be output on the analog output. PPM
concentration is obtained by multiplying the percentage
concentration by 10 000, so full scale should be chosen
accordingly. Scale ranges from 0 (4 mA) to Full Scale (20 mA).
The full-scale value for the analog output can be entered into the Full Scale field by
highlighting it using the F4 / F3 keys, then pressing
↵
to enter data entry mode. Enter in the
desired full-scale value, then press
↵
again to save. Press Esc to discard any changes.
Above the Full Scale field are two check boxes marked Track and Hold . When Track is
selected, the analog output value will track with the displayed concentration value even when
the analyzer is in back purge mode; hence, when Track is selected, during zero calibration
cycles and any other times when the analyzer is placed into back purge mode, the signal
output to the DCS will be zero. When Hold is selected, the analog output value will hold the
last good process value any time the analyzer switches into back purge mode until the
analyzer is back on line in sampling mode; in this way, the analog output will never drop to
zero even during zero calibration cycles or other times the analyzer is placed into back purge
mode. Highlight the desired analog output behaviour by using the F4 / F3 keys to highlight
the desired choice, then pressing
↵
to select.
After making any changes on this sub-panel, it will be necessary to save them permanently
to the analyzer. Use the F4 / F3 keys to highlight the Save button in the bottom right-hand
corner of the sub-panel, then press
↵
to save changes to the analyzer. Alternatively, to revert
all changes made on this sub-panel, use the F4 / F3 keys to highlight the Revert button and
press
↵
to confirm.
4.8.2 Calculation Sub-Panel
The Calculation sub-panel shown in Figure 41 is used to set a variety of parameters that
are related to the calculation of analysis results by the control computer.