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Advant

Smart Device (HART

) Interface User’s Guide

Chapter 2 Installation

2-38 3BUR 001 085R0001 REV A

2.3.1.8 Power Considerations

The common mode voltage between the SHIM, termination panels, and their power supply

cannot exceed 0V dc.

2.3.1.9 Special Wiring Considerations

There are several types of intrinsic safety barriers configurations used when operating in

environments that require intrinsic safety. Use either shunt-diode safety barriers or isolating

repeaters.

NOTE

You can use most intrinsic safety barriers, provided 2-way digital communication

between smart transmitters and the SHIM is not impeded.

2.4 Smart Device Data Storage Considerations

This section discusses how the data from smart devices is stored, and suggests a technique you

can use in programming or configuring smart devices and in configuring the Smart Device

Interface. The technique is intended to optimize the utilization of memory and avoid problems

that can make a smart device layout inefficient. In addition, the assigning of CCF channel

numbers in the Smart Device Interface is discussed to show the effect of the technique on their

usage. A channel should not be used by more than one device.

As Figure 2-29 shows, there is one analog channel table in a AC 410 or AC 460 subsystem to

support analog inputs from the smart devices.

An analog input FCM of a continuous loop can acquire the value of a variable in the analog

channel table. It is accessed as an input by one FCM.

NOTE

An AC 410 or AC 460 subsystem has one analog channel table to support smart

device inputs. If one smart device stores its four inputs in analog channels 1

through 4, another smart device should not store its input data in these analog

channels.

Figure 2-29. Smart Device/CCF Loop Communication Scheme

CCF Data Base

CCF Continuous Loop

Analog

Input

Other

FCMs

Smart Device Interface

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Black Box IC108A Betriebsanweisung Seite 50