This is PLC Program for single tank level controlling with alarm controlling.
We need to control the level of water in the tank.
Control the water level by simple PLC logic. Give the alarm for high level in
the system and acknowledge button for the alarm reset .Write the ladder diagram
logic for this application.
Problem Diagram
Problem
Solution
To solve this this example we
are using PLC programming. Here we
have a tendency to use 2
sensors for level measurement,
one is for prime level and
second is for low level.
We use feeding valve for feeding Cycle for the tank and discharge valve
for discharging cycle for the tank. Each
valve are controlled by sensors.
So once the water level goes
below low level then feeding valve can
activate mechanically and water level senses the high level then
discharging method are activate mechanically.
Program
Here
is PLC program for single tank level controlling with alarm
controlling using PLC.
List
of inputs/outputs
Digital
inputs:-
Main switch:-I1.1
Start button:-I0.0
Stop button:-I0.1
High level:-I0.2
Low level:-I0.3
Feeding valve:-Q0.1
Discharge valve:-Q0.2
Digital
outputs:-
Master coil:-Q0.0
Feeding valve:-Q0.1
Discharge valve:-Q0.2
Mixer motor:-Q0.3
Ladder
diagram for single tank level controlling with alarm controlling using PLC.
Program Description
In network 1 we tend to
used latching circuit for master coil ON
(Q0.0) output.it will be
started by pressing START Push button (I0.0) and stop by pressing STOP
pushbutton (I0.1).
When cycle are going to be begin then system check level of the
tank. If tank level is low then then feeding method can begin and tank level is high then
Discharge cycle can begin.
Here we've taken NO contact for each sensors within the program for simplicity. It will be done by relay logic in field otherwise you will choose such variety of sensors.
In network 2,when tank can observe low level then low level sensor (I0.2) is going to be
activated and feeding cycle are going
to be ON. Here we've
taken NC contact of high level sensor
(I0.3) therefore once PLC can observe high
level then it'll STOP feeding
cycle.
In network 3,when tank can observe high level then high
level sensor (I0.3) is to
be activated and discharging cycle are going to be ON. Here we've
taken NC contact of low level sensor (I0.2) therefore once PLC can observe low level then it'll STOP discharge cycle.
In network 4,
mixer motor (Q0.3) will remain ON when discharge valve is ON.
In network 5 when high level (I0.3) is detected, alarm
(Q0.4) will be activated.
In network 6 when acknowledge button is pressed, alarm
will be reset.
Note:-Application is only for learning and
educational purpose .Above application may be different from actual
application. This application can be done in other PLC also. Users are
responsible for correct operation of the PLC system and for any possible
injuries and or material damages resulting from the use of this program. It is
necessary to take care of safety during implementation, installation,
maintenance and operation.
All parameters and
graphical representations considered in this example are for explanation
purpose only, parameters or representation may be different in actual
applications. Also all interlocks are not considered in the application.