Emerson I-0021 Manuel D’Utilisation

Page de 238
NGA-2000 System Calibration
90003482(2) [NGA-e (MLT-Software 3.2.X)] 07/98
NGA 2000
Supplement - 31
4.3 Running Single Analyzer Calibration
A single analyzer calibration also needs to switch appropriate system valves.
The difference to the system calibration is that calibration procedure of AM is already running
and we have to respond upon this state.
The reaction is possible by watching any change of the LON-variable CALSTAT.
• 
CALSTAT_ZERO (zero calibration in progress): 
switch off belonging sample valve and 
switch on zero valve.
• 
CALSTAT_SPAN (span calibration in progress):
switch off belonging sample valve and 
switch on span valve appropriate to 
current state of CRANGE-variable.
• 
CALSTAT_DONE (calibration finished):
switch on sample valve and switch off 
calibration gas valves.
After a calibration command the AM itself is responsible to wait the required purge times until
calibration actually is done.
The reaction onto a CALSTAT-change is only active if no system calibration is running.