Runtime Test Cases
Inputs
Outputs
Physical Elements
I:1/2 = 1
O:2/0 = 1 Open Inlet Valve 1
I:1/2 = 0 & I:1/1 = 0
O:2/0 = 1 Open Inlet Valve 1
I:1/1 = 1
O:2/0 = 0 Close Inlet Valve 1
I:1/1 = 1
O:2/1 = 1 Open Inlet valve 2
I:1/0 = 1
O:2/1 = 0 Close Inlet Valve 2
I:1/0 = 1
O:2/2 = 1 Run Agitator Motor
T4:0/DN = 1
O:2/2 = 0 Stop Agitator Motor
T4:0/DN = 1
O:2/3 = 1 Open Outlet Valve
I:1/2 = 1
O:2/3 = 0 Close Outlet Valve
PLC Program for Heating Liquid in the Tank by Heater
This is a PLC Program for Heating Liquid in the Tank by Heater.
Problem Description
Controlling heating of Liquid in the tank using heater. Implement this process in PLC using Ladder
Diagram programming language.
Problem Diagram
Diagram
to
control
the
heating
of
liquid
in
the
tank
Problem Solution
To detect high and low level of liquid in the tank, two level switches are used which gives output in digital
terms, that is when corresponding levels are detected, it gives output high otherwise remain low.
To control level of this system, Single Acting Piston valve can be used which has two states, either fully
open or fully close and to heat the liquid, heater is used.
Low Level Switch is mounted at the bottom of the tank and Level High switch is mounted at the side-upper
most position.
Heater is installed inside the tank and temperature sensor such as RTD or Thermocouple may be used to
detect the temperature of liquid in the tank.
PLC Program
Here is PLC program for Heating Liquid in the Tank by Heater, along with program explanation and run
time test cases.
List of Inputs and Outputs
I:1/0
= Level High Switch
(Input)
I:1/1
= Level Low Switch
(Input)
O:2/0
= Inlet Valve
(Output)
O:2/1
= Outlet Valve
(Output)
O:2/2
= Heater
(Output)
I:1/14 = Start
(Input)
I:1/15 = Stop
(Input)
N7:1
= Temperature Data
(Register)
|
