Galvanic Applied Sciences 962-AGX, Operation Manual

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Revision 1 13 9/10/2019
The control cabinet contains the electrical hardware necessary for the operation of the
analyzer. Under normal operating circumstances, the interior of the control cabinet maintains
a general purpose area classification through a Type Z purge system. Both visual and
electrical (contact closure) indications are provided for monitoring the status of the control
cabinet purge.
1.3 Sample System
The 962-AGX analyzer system utilizes a straight-through flow pattern from the ‘sample in’ to
the ‘sample out’ port. A pressure differential is required between the sample probe location
and the sample return point. The analyzer plumbing incorporates an adjustable metering
valve to control the sample flow rate.
Incoming sample gas is filtered to 60 microns. The measurement cell contains a fixed
quantity of sample that is monitored by UV radiation for spectroscopic analysis.
Analyzer zeroing is accomplished by introducing higher pressure zero gas upstream of the
measurement cell. The zero gas flushes the entire sample system (probe to vent) and allows
readings to be taken through the measurement cell when no absorbing species are present.
To the sample system, zeroing and back purging are identical.
A temperature-controlled oven maintains all components exposed to the gas sample at
higher than dew point values and the measurement cell is electrically heated. The typical cell
temperature is 50
o
C.
1.4 System Operating Control
The analyzer system operation is controlled by a dedicated data acquisition system which
provides supervisory control, performs all calculations and provides the user interface.
The system includes a graphic display which provides full screen display of key system
control parameters and their status, a digital display of the instantaneous value of the H
2
S,
and historical graphic displays of the H
2
S. The display monitor is mounted on the door of the
control cabinet. Cabinet access is not required for viewing or operation.
The H
2
S output can be configured as a loop powered 4 – 20 mA signal and the system status
is available via relay contacts. An RS485 serial port is also provided which can be used for
Modbus communication.
A hand held key pad is provided for user interface with the analyzer. Operation of the system
with the keypad is described in Section 4. As an alternative, a web based graphical user
interface (GUI) can be used to view and enter information on a remote basis (Section 5).