Emerson Rosemount 370XA, System Reference Manual

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System Reference Manual 370XA Gas Chromatograph
7P00370-H01 APRIL 2014
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Figure 3-3. Wiring for a digital output for fail-safe mode
3.12.3 Analog input
You can use the analog input to monitor and generate an alarm from
an external signal such as a pressure transmitter on the carrier gas
bottles or as a composition component input from another analyzer
such as a moisture or H
2
S analyzer. The analog input is optically
isolated and requires external loop power.
Figure 3-4. Analog Input wiring with an external power supply and a loop
powered transmitter
3.12.4 Analog outputs
The 370XA has two analog outputs. Each analog output can be used
to transmit a GC variable, such as an energy value or a component
concentration, as a 4-to-20 mA signal. The outputs are self-powered
and require a loop resistance of less than 500 ohms.