Overview - Honeywell Series A User Manual

Overview

The key to fieldbus interoperability is the User Application or Function Block
Application Process (FBAP) that defines standard function blocks that can reside in field
devices and be interconnected as a distributed process control system. A function block is
a named entity that has inputs, outputs, and parameters. It performs certain functions that
operate on its inputs and produce outputs in accordance with its assigned parameters. The
Fieldbus Foundation Function Blocks are similar in nature to the Function Blocks used to
build control strategies in the Control Builder application in the Experion system.
The Fieldbus Foundation provides the standard Function Blocks listed below for basic
control functionality. They also support additional blocks for more complex applications.
Please refer to the applicable Fieldbus Foundation specification for more information
about these additional blocks.
Function Block
Analog Input
Analog Output
Bias/Gain
Control Selector
Discrete Input
Discrete Output
Manual Loader
Proportional/Derivative
Proportional/Integral/Derivative
Ratio
Function blocks make it possible to build a control loop using fieldbus devices that
include the appropriate Function block types. For example, a pressure transmitter that
contains an Analog Input and Proportional/Integral/Derivative blocks can be used with a
valve containing an Analog Output block to form a control loop, as shown in the
following figure.
R400 Experion PKS Series A Fieldbus Interface Module User's Guide
July 2010
10.2. Standard Function Blocks
Abbreviation
AI
AO
BG
CS
DI
DO
ML
PD
PID
RA
Honeywell
10. Appendix A
Class
Input
Output
Control
Control
Input
Output
Control
Control
Control
Control
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