0 fcs modules, 1 overview, 2 fcs module description – Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller FLEXIBLE CONTROL STRATEGIES User Manual

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2.0 FCS MODULES

2.1 OVERVIEW

The Flexible Control Strategy (FCS) modules are the building blocks of the controller functionality.
The modules are presented symbolically with inputs and outputs to eliminate the necessity of learn-
ing a programming language; however, each symbol actually represents coded instructions that
are executed by the Process Control Station (PCS). The order in which the modules are con-
nected determines the instruction flow executed by the PCS. Because each module is a coded in-
struction set, connecting the modules does not require any physical alteration to the PCS hardware
but is accomplished by configuring an assigned list of memory datapoints. The assigned list is
called a worksheet and after the worksheet is completed, the connected datapoint values are en-
tered into the PCS memory. Connecting the datapoints is sometimes called

wiring, a term that is

still carried-over today from the earliest electronic processors when the hardware functions of a de-
vice were selectively connected one-to-another with jumper wires.

2.2 FCS MODULE DESCRIPTION

As shown in the figure below, each module has an associated set of input signal designators
shown as diamonds, output signal points shown as a circle(s), and an operational function code
(FC) where applicable. The wirelist datapoints assigned to the input diamonds, output circle(s),
and function code (if applicable) are all listed in the

Inputs table that is provided with each module

description. A separate

Functions table, which describes each function code, is also provided for

those modules that perform mathematical or logical functions.

Logic Module A

The

Inputs table above indicates the wirelist datapoint assignments for inputs A and B are B127

and B128 respectively. The wirelist datapoint assignment for the FC is B129 and the output value
that is accessible to other modules in the FCS sequence is L097.

FCS signals are of two types: logical L-values (0 or 1) and numeric C-values. Logical L-values are
shown as solid diamonds for input signals and solid circles for output signals. Numeric C-values
are shown as open diamonds for input signals and open circles for output signals. Logical and nu-
meric values can not be cross-wired from one module to another, that is, the logical output of one

Logic Functions

FC

OUTPUT

FC

OUTPUT

0

A

4

A OR NOT B

1

A OR B

5

A AND NOT B

2

A AND B

6

J-K LATCH

3

A XOR B

7

D LATCH

Invert output if FC = FC + 128

Inputs

WIRELIST

SYMBOL

DATA

TYPE

ASSIGNED VALUE

B127

A

L

B128

B

L

B129

FC

N/A

Output Datapoint: L097

Section 2. FCS Modules

3-1TXT

2–1

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