Function Blocks
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Function Block Reference Guide
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2.19 DI Function Block,
continued
Table 2-20 Digital Input Configuration Parameters
Properties Group
Parameter
Index#
Parameter Description
Value or Selection
Address
I/O Module
0
Address of select I/O Module
From 6 to 16
Channel
Channel on selected I/O Module
From 1 to 6
1
If INVERT is selected, OUT = inverse of physical input.
The slash will be present in the CONTACT symbol only
when the invert box is selected on the dialog box. (see
below)
Example
Figure 2-17 shows a Function Block Diagram using DI function blocks in a basic Series Parallel Circuit.
LS 1
LS 2
SOL 1
Coil
This is a basic series-parallel circuit. If Limit Switch 1
(LS1) is ON and Limit Switch 2 (LS2) is ON, or
if pushbutton PB1 is ON, then Solenoid 1 is turned ON,
otherwise it is OFF. Note “power flow” can be delivered
in either of two paths to the solenoid.
PB1
Equivalent Boolean Logic Expression
UMC 800 Logic
A = LS1, B = LS2
D = Output
(A * B) + C = D
AND
Symbol
A
B
C
C = PB1,
OR
Symbol
D
OR
This uses a basic 2 Input AND block
and a 2 Input OR block.
6 Function blocks are used.
AND
Figure 2-17 Digital Input Function Block Example
