Galvanic Applied Sciences 943-TGX-CE, Operation Manual

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Revision 4 43 April 2020
When this indicator is in the ‘Calibrate’ state, the analyzer is not measuring the process
tail gas. After a calibration cycle is complete, the Calibrate state will persist for a specified
time interval (the Zero Hold Interval), allowing process gas to reach the measurement cell
and the analyzer concentration measurements to return to stable process values prior to
returning to the Run state.
If there are any faults currently present (i.e. Status relay is in fault state) the Mode
indicator CANNOT switch to Calibrate
– Calibration is ONLY possible when all fault
conditions are cleared, and the Status relay is in the Normal condition. The only
condition under which the Status relay can be in Fault while the Mode relay is in
Calibrate is if the analyzer power is off.
3.5.2.4 Control
The Control output indicates whether the analog output signals are valid. Table 6
describes the Control relay.
Table 6: Control Relay States
Condition Display Indicator Colour Explanation
Auto Green
ALL the following conditions are true:
•
Status indicator is Normal (i.e. no
fault conditions present)
•
Mode indicator is in Run state
(i.e. analyzer is not performing a
zero calibration)
•
Online / Offline switch is in the
Online position (i.e. analyzer is
not under maintenance)
•
Analyzer power is on
Manual Yellow
At least one of the conditions for the relay
to be in the Auto state is NOT true.
When the relay is in the Auto state, the analyzer is indicating that it believes that the data
being output on the analog outputs are valid current measurements of the tail gas process
steam. If the Control relay is in the
Manual state, this indicates that the analyzer believes
that the data being output may not be valid. The purpose of this indicator is to signify
when the analyzer outputs are suitable for use as closed loop control inputs. When this
indicator is in the Manual state, no control action should be taken based on the analyzer
output signals. This indicator is generated on the basis of the other analyzer indicators,
as well as the condition of the
Online / Offline mode toggle on the display (refer to
Section 4.3.1). The Control relay state is automatically returned to Auto once all the
conditions required for the Auto state have been met. While the Control relay is in the
Manual state, any analog output that is configured as Hold
will be held.