Thermo Scientific Omni FTIR Multi Gas CEMS, Инструкция по эксплуатации

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Interfacing a DCS/PLC with the Omni FTIR Multi Gas CEMS
Establishing Communications
Thermo Fisher Scientific Omni FTIR Multi Gas CEMS Instruction Manual C-3
This section provides information on the methods available for retrieving
system data, accessing system status conditions, initiating system events,
and checking system calibration.
The 4-20mA analog output signals are labeled “ANALOG OUTPUT X1”
on the electrical panel assembly, which is accessible from the rear of the
rack. Two sets of terminals are labeled 1-11 for the individual outputs, with
the positive side on the right and the return side on the left. The positive
side terminal includes a disconnect feature so that externally connected
components may be disconnected from the current loop for local testing
and diagnostics.
The 4-20mA analog outputs are each capable of driving a loop resistance
down to 500 Ohms.
Refer to Table C–1 for the analog output terminal assignments. Refer to
Modbus Protocol Table B–1 , “Read Register” for Modbus methods for
retrieving data. Refer to Figure C–2 to locate the pins on the rear panel
terminal connector.
Table C–1. Analog Output Connections
Analog No. Signal
1 SO2
2 NO
3 NO2
4 N2O
5 NH3
6 HCl
7 HF
8 CO
9 CO2
10 H2O
11 SF6
Establishing
Communications
Analog Outputs