Honeywell UMC800 - Figure 2-43 2 OR Function Block Example

Function Blocks
3/99 Function Block Reference Guide 129
2.46 2OR Function Block,
continued
Example
Figure 2-43 shows a Function Block Diagram using a 2OR function block.
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
DOR
This uses a basic 2 Input AND block
and a 2 Input OR block.
6 Function blocks are used.
AND
Figure 2-43 2OR Function Block Example