Subtract (Sub); Relay Ladder; Structured Text; Function Block - Allen-Bradley Logix5000 Reference Manual

Subtract (SUB)

dest := sourceA - sourceB;
Compute/Math Instructions (CPT, ADD, SUB, MUL, DIV, MOD, SQR, SQRT, NEG, ABS)
The SUB instruction subtracts Source B from Source A and places the result in
the Destination.
Operands:

Relay Ladder

Operand
Source A
Source B
Destination

Structured Text

Use the minus sign "−" as an operator in an expression. This expression subtracts
sourceB from sourceA and stores the result in dest.
See Structured Text Programming
within structured text.

Function Block

Operand
SUB tag
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Type Format
SINT Immediate Tag
INT
DINT
REAL
A SINT or INT tag converts to a DINT value by sign-extension.
SINT Immediate Tag
INT
DINT
REAL
A SINT or INT tag converts to a DINT value by sign-extension.
SINT Tag
INT
DINT
REAL
for information on the syntax of expressions
Type
FBD_MATH
Description
Value from which to subtract Source B
Value to subtract from Source A
Tag to store the result
Format Description
structure SUB structure
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