Thermo Scientific Omni FTIR Multi Gas CEMS, Instruction Manual

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Thermo Fisher Scientific Omni FTIR Multi Gas CEMS Instruction Manual C-1
Appendix C
Interfacing a DCS/PLC with the
Omni FTIR Multi Gas CEMS
Establishing communications between the Omni FTIR Multi Gas CEMS
and a DCS/PLC involves making the physical connections between devices
and using an appropriate method/application to establish data
communications.
For details on interfacing a DCS/PLC with the Omni FTIR Multi Gas
CEMS, see the following topics:
●
“ Introduction ” on page C-1
●
“ Connecting a DCS/PLC to the Omni FTIR Multi Gas CEMS ” on
page C-2
●
“ Establishing Communications ” on page C-3
Typical communications functions provided by the Omni FTIR Multi Gas
CEMS include:
Checking data values
Reading system and alarm status
Triggering events (such as calibration checks and probe blowbacks)
The Omni FTIR Multi Gas CEMS provides several methods for
establishing data communication with a DCS/PLC including:
Analog output connections (4-20mA)
Digital I/O connections (5V TTL logic)
Modbus protocol (over RS-232 or Ethernet)
Introduction