4Sub Function Block - Honeywell UMC800 Reference Manual

2.67 4SUB Function Block

Description
The 4SUB label stands for the Subtraction mathematical operation (4 Inputs). This block is part of the
Math category. It looks like this graphically on the Control Builder.
Function
Subtracts three analog inputs (X1,X2,X3) from Y input to get an output.
Input
X1 = First analog input
X2 = Second analog input
X3 = Third analog input
Y = Fourth analog input (number to subtract from)
Note: All four inputs must be connected. Unconnected inputs default to zero.
Output
OUT = Calculated Value
Block Properties
Double click on the function block to access the function block properties dialog box.
Block Order (Read Only)
You can change the assigned execution order number by selecting "Execution Order" in the "Configure"
menu and arrange the order to suit your control strategy.
Example
Figure 2-71 shows a Function Block Diagram using a 4SUB function block.
Y - X1 - X2 - X3 - X4 = OUT
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Figure 2-71 4SUB Function Block Example
Function Block Reference Guide
Function Blocks
201