Galvanic Applied Sciences 943-TGX-CE, Operation Manual

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Revision 4 47 April 2020
that may cause the output data to become invalid, this control should be toggled to the Offline
(red) state by using the F4 / F3 keys to highlight it and then pressing
↵
to toggle it. When this
control is set to Offline mode, it will become red. At the same time, the Control relay state
will change from the Auto state to the Manual (yellow) state, indicating that the analyzer
believes the output data to be invalid. Once maintenance is complete, this toggle should be
set back to the Online state by again highlighting it using the F4 / F3 buttons and pressing
↵
.
The analyzer’s Online or Offline status does not affect the operation of the analyzer in any
way. Rather, this function has been implemented as a convenience to the operator, as it
provides an easy way for the operator to indicate to the control room that the analyzer is
currently undergoing maintenance or servicing and thus the data being output by the
analyzer is not valid.
When the control is toggled from Offline to Online, the Control relay will change state from
Manual to Auto ONLY if the conditions listed as prerequisite for the Auto state in Table 6
have been met.
4.3.2 Concentration Fields
The concentration fields shown in Figure 20 are non-editable fields that show the current
value of the concentrations for all analyzed components.
Figure 20: Analysis 1 Concentration Fields
The analyzer’s physical measurement range, which is determined by the length of the
measurement cell, is optimized for typical on-ratio (that is to say, non-upset) concentrations
of H
2
S and SO
2
. COS and optionally CS
2
concentrations are also displayed here. The sulfur
vapour (S
vap
) is monitored to indicate when there may be a problem with the probe condenser
“cold finger” at the tip of the sample probe (refer to Section 3.4.2) and to prevent sulfur
plugging inside the analyzer sample handling system.
4.3.3 Air Demand
The Air Demand field and Air Demand trend graph shown in Figure 21 show the current
calculated Air Demand (% Excess Air) and the recent trend in the Air Demand data. The Air
Demand field is read-only and cannot be edited.