Thermo Scientific Omni FTIR Multi Gas CEMS, Инструкция по эксплуатации

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Modbus Protocol
Modbus Parameters Supported
B-6 Omni FTIR Multi Gas CEMS Instruction Manual Thermo Fisher Scientific
Table B–2. Modbus Write Registers
Register Number Variable
201 SYSTEM COMMAND
Table B–3. System Command Values
Value Description System Status Description
0 N/A
1 SAMPLE MODE Sample solenoid valve is triggered, only sample flow
is pumped into the gas cell.
2 BLOWBACK MODE System auto blowback is triggered. At the end of
three pulsed blowbacks, the system is switched
back to sample mode.
3 BACKGROUND MODE Sample valve is closed, and instrument zero and
flowback flows are triggered. This mode is
independent of spectrum collection.
4 SAVE BACKGROUND The FITR is commanded to collect the spectrum. In
general, this mode should be selected after mode 3
is trigged.
5 BACKGROUND MODE
& SAVE BACKGROUND
This mode is the combination of mode 3 and mode 4.
After flowing the zero air into the gas cell for five
minutes, the FTIR starts to collect zero air spectrum,
and then saves the spectrum to replace the file
“C:\backgrounds\bkg.spa”. At the end, the system is
switched back to sample mode.
6 CHECK ZERO MODE In this mode, the system is running just like the
sample mode. At the sample time, the zero air flows
into the probe and is pumped into the gas cell. This
mode is used to test the system zero offset.
7 CHECK SPIKE MODE The standard gas flows into the probe at a flow rate
of 10% sample flow rate. In general, a trace gas
such as SF6 is used to determine the dilution ratio of
standard gas flow versus the sample flow.
8 CHECK SPAN MODE Calibration gas flows into the probe, and is pumped
into the gas cell. This mode is used to check the
system span
9 CHECK SPAN2 MODE
(N/A) This mode is used to perform an extra span check, in
addition to the target gas.
10 CHECK SPAN3 MODE
(N/A)