Application:-Set wiring
in the electrical panel so when operator has to operate two switches to operate
one lamp. Make electrical control wiring using two switches and one lamp. Also
draw truth table for application and write PLC program using ladder diagram
language.
Diagram:-Electrical
wiring diagram and truth table of AND operation
Explanation:-AND
gate operations very important logic in various industrial application. For
example purpose we have taken two switches S1 and S2 as shown in above figure.
So if operator wants to ON lamp, he has to ON both the switches as per the AND
operation. So S1 and S2 must be ON if we want to ON lamp.
In truth table all the conditions has been shown for explanation,
it can be easily learned by simple conditional logic,
As per truth table,
If S1=ON AND S2=ON, then R=1
If S1=ON AND S2=OFF, then R=0
If S1=OFF AND S2=ON, then R=0
If S1=OFF AND S2=OFF, then R=0
So output will be ON only in first condition.
PLC
program:-Write the ladder program for AND gate operation
using ladder diagram language
Here for ladder logic we can use any PLC system. For
PLC logic we need digital inputs and outputs.
For our application all switches are digital inputs
and lamp is digital output. So define digital input address and output address
as per below explanation,
Digital
inputs:-
S1=I0.0
S2=I0.1
Digital
Output:-
Lamp=Q0.0
Memory coil:-
M=Memory bit
PLC
program Explanation:-
In network we have considered two digital inputs for
two switches S1 and S2. So we have taken NO contact of S1 (I0.0) in series with
S2 (I0.1) for AND operation. So when both are ON, memory bit (M0.0) will be ON.
In network 2 we have taken NO contact of memory bit
(M0.0) to operate lamp (Q0.0).