Latched Alarms; Calibration Of Gas Detectors - ABB 800xA Operation

Section 2 Operation

Latched Alarms

The gas detector inputs and the loop monitored digital inputs have a latched alarm in
the data base. The latched alarm can be reset (Reset Latch) for individual signals
from the operator dialog.

Calibration of Gas Detectors

The calibration of pellistor gas detectors connected to DSAI 165/DSTA 191 is
performed from the operator workplace.
Check that the loop current (adjustable 170-350 mA) is according to the detector
specifications. The procedure is as follows:
1.
2.
3.
4.
5.
6.
7.
8.
This has changed values in the database. Perform a backup of the controllers
(DUAP or DUTDB) to save the changes after the calibration.
3BNP004849-600
Select the GI object, bring up the Object Display.
Select the Extended Faceplate, tabulator 'Calibration'.
Press the 'Enter' command button in the Test mode frame. The test mode (OK)
shall be indicated (filled square).
The loop and hardware are verified by a system test program and all event
handling and actions are blocked.
Select the calibration value, and enter the value 0 (%) for zero calibration.
Ensure that the detector is supplied with clean air and press the 'Cal' command
button.
Calibration 0 shall be indicated (filled square).
Select the calibration value, and enter the value, e.g. 50, (%) for the test gas you
are using.
Ensure that the detector is supplied with the test gas and press the 'Cal'
command button.
Calibration X shall be indicated (filled square).
The detector is now calibrated. Press the 'Leave' command button in the Test
mode frame. The test mode (off) shall be indicated (unfilled square). Event
handling and actions are activated now.
Latched Alarms
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