Emerson FB3000, Руководство по установке

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FB3000 RTU HART ® I/O Module Field Installation Guide
D301918X012
June 2021
5
Wiring the Module
DANGER
Ensure the RTU is in a non-hazardous area. Never open the enclosure in a hazardous area.
DANGER
EXPLOSION HAZARD: Ensure the area in which you perform this operation is non-hazardous.
Performing this operation in a hazardous area could result in an explosion.
You can wire HART channels for different modes of operation.
Point-to-Point Mode
In Point-to-Point mode, the HART link allows both a 4-20mA analog current mode signal as well as
the modulated HART digital signal riding on top of it. Depending upon the HART device connected,
you can configure the channel as an AI (which means the 250 ohm resistor is enabled) or an AO
(which means the 250 ohm resistor is disabled).
Figure 1 shows how to wire all four HART channels in point-to-point mode. In this case, each HART
channel only communicates to a single HART device. You choose whether a given channel serves as
an input or output in FBxConnect. The 24V internal loop power supply powers the HART devices.
The HART interface only sinks current, it cannot source current. As an output, each channel
simultaneously provides an analog current signal output (sink current only at 4-20 mA) and a HART
signal modulated on top of it.
Figure 1. HART Wiring – Point-to-Point Mode
HD HART Device