Inst ToolsInst ToolsInst Tools
  • Courses
  • Automation
    • PLC
    • Control System
    • Safety System
    • Communication
    • Fire & Gas System
  • Instrumentation
    • Design
    • Pressure
    • Temperature
    • Flow
    • Level
    • Vibration
    • Analyzer
    • Control Valve
    • Switch
    • Calibration
    • Erection & Commissioning
  • Interview
    • Instrumentation
    • Electrical
    • Electronics
    • Practical
  • Q&A
    • Instrumentation
    • Control System
    • Electrical
    • Electronics
    • Analog Electronics
    • Digital Electronics
    • Power Electronics
    • Microprocessor
  • Request
Search
  • Books
  • Software
  • Projects
  • Process
  • Tools
  • Basics
  • Formula
  • Power Plant
  • Root Cause Analysis
  • Electrical Basics
  • Animation
  • Standards
  • 4-20 mA Course
  • Siemens PLC Course
Reading: PLC Program to Read Temperature in PLC
Share
Notification Show More
Font ResizerAa
Inst ToolsInst Tools
Font ResizerAa
  • Courses
  • Design
  • PLC
  • Interview
  • Control System
Search
  • Courses
  • Automation
    • PLC
    • Control System
    • Safety System
    • Communication
    • Fire & Gas System
  • Instrumentation
    • Design
    • Pressure
    • Temperature
    • Flow
    • Level
    • Vibration
    • Analyzer
    • Control Valve
    • Switch
    • Calibration
    • Erection & Commissioning
  • Interview
    • Instrumentation
    • Electrical
    • Electronics
    • Practical
  • Q&A
    • Instrumentation
    • Control System
    • Electrical
    • Electronics
    • Analog Electronics
    • Digital Electronics
    • Power Electronics
    • Microprocessor
  • Request
Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Inst Tools > Blog > PLC Tutorials > PLC Program to Read Temperature in PLC

PLC Program to Read Temperature in PLC

This is a PLC Program to read the temperature in PLC. Learn PLC programming using example problems and solutions.

Last updated: November 3, 2023 12:21 pm
Editorial Staff
PLC Tutorials
3 Comments
Share
5 Min Read
SHARE

This is a PLC Program to read the temperature in PLC. Learn PLC programming using example problems and solutions.

Contents
Read Temperature in PLCProblem DiagramProblem SolutionI/O ListPLC Ladder diagram to read the temperaturePLC Logic Explanation

Read Temperature in PLC

Problem Description

Write a PLC program in which we can monitor the actual temperature.

Here we are using an external temperature controller and its output is also connected to PLC for monitoring the temperature of material in the tank.

Problem Diagram

Read Temperature in PLC

Problem Solution

RTDs devices with resistance that changes with temperature changes in a linear way.

This resistance value will change as temperature changes and by supplying a constant current, the measured voltage drop across the resistor can be used to determine the new resistance, and thus the temperature.

RTDs come in a variety of types, with the most common type is a PT100. It’s made from platinum that has been calibrated to be 100 ohms at 0 degrees C.

In above application, we want to measure material temperature of the tank, for that we use RTD sensor which will measure temperature of the tank and give signal to the temperature controller.

Temperature controller will send signal in the form of voltage (0-10V DC).If RTD detect 0degree temperature, it will send 0V DC and if maximum temperature detected, it will send 10V DC to PLC.

Temperature controller is directly connected to the PLC so PLC will read voltage.

Note: – Here we consider simple application for explanation. We need to measure material temperature of the tank by using RTD sensor. And also consider other components for control purpose.

Assume Scaling range of temperature controller is 0-100°C=0 to 10V DC and according to this signal PLC consider 0 to 27648.

I/O List

M memory

  • Analog value from the temp controller :- MW100
  • Actual value from the temp controller :- MD104
  • Multiplication :- MD108
  • Actual temperature in °C :- MD112

PLC Ladder diagram to read the temperature

PLC INT Value Conversion
PLC Temperature Controller
PLC Temperature Monitoring

PLC Logic Explanation

For this application, we used S7-300 PLC and TIA portal software for programming. We can implement this logic by using other PLC’s also.

Network 1:

In this network, we implement logic for value conversion. It is necessary to convert value from INT to DINT for multiplication purpose or for calculation. So by using conversion instruction analog value from the RTD (MW100) is converted into actual analog value (MD104).

Note:- Temperature controller provides 0-10V DC signal to PLC. ADC converter or analog input module will convert this analog signal into digital form, and the range of this digital signal is 0 to 27648. This digital range may change from one PLC to another.

Network 2:

we have the RTD temperature range which is 0 to 100 degc and the output voltage range is 0 to 10V DC. So we need to scale this voltage output in terms of temperature reading. Here multiply the value as per equation and final value will be stored in MD108.

Note:-Here temperature controller and temperature measurement range is 0-100°C.

Network 3:

Now for final result multiplied value is divided by 27648, result will be stored in MD112 (Actual temperature in °C).

Note:- Above application may be different from actual application. This example is only for explanation purpose only. We can implement this logic in other PLC also. This is the simple concept of temperature reading in S7-300 PLC, we can use this concept in other examples also.

All parameters considered in example are for explanation purpose only, parameters may be different in actual applications.

Author: Bhavesh

If you liked this article, then please subscribe to our YouTube Channel for PLC and SCADA video tutorials.

You can also follow us on Facebook and Twitter to receive daily updates.

Read Next:

  • Failsafe Wiring Practices
  • Basics of Switch NC NO Contact
  • Sinking vs Sourcing
  • PLC Equivalent Logic Gates
  • PLC Logic Functions
Don't Miss Our Updates
Be the first to get exclusive content straight to your email.
We promise not to spam you. You can unsubscribe at any time.
Invalid email address
You've successfully subscribed !

Continue Reading

Structured Text vs. Instruction List for PLC Programming
How-to do Security of SCADA Systems?
FOR DO Statement in SCL Language
How to Configure an Alarm in InTouch SCADA?
PLC Commissioning and Testing Procedure (Programmable Logic Controller)
Types of Script in Intouch Scada
Share This Article
Facebook Whatsapp Whatsapp LinkedIn Copy Link
Share
3 Comments
  • Indra Mohan Prasad Singh says:
    November 21, 2018 at 7:55 am

    good

    Reply
  • Rahul says:
    September 24, 2019 at 11:22 am

    When RTD sense 50 Celsius one out put is on writ program in RS logix 500

    Reply
  • Balotiya Yuvraj says:
    August 17, 2021 at 2:49 pm

    Can you describe hydraulics press machine in details.

    Reply

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Stay Connected

128.3kFollowersLike
69.1kFollowersFollow
210kSubscribersSubscribe
38kFollowersFollow

Categories

Explore More

Batch Simulator PLC Example Program using LogixPro Simulator
Communication between Wincc and Tia Portal
Structured Text PLC Code for Sequential Process Data Storage
Allen Bradley PLC to PLC Communication in Studio 5000
PLC Batch System for 4 Tanks Mixing using CX-Programmer
How to import GSD files into the TIA Portal? – Siemens PLC
Programmable Logic Controller (PLC) Scan Time – Types, Theory
Relay circuits

Keep Learning

Free Download PLC Book

#10 PLC Best Practices – Assign Register Blocks by Function

PLC program to control pump

Troubleshooting PLC Permissive Inputs

PLC Instruction List Example for Level Control of Tank

PLC Instruction List Example for Level Control of Tank

Software Troubleshooting Errors and Faults in Siemens PLC

Software Troubleshooting Errors and Faults in Siemens PLC

Industrial motor control using PLC instruction list programming

PLC Instruction List for Motor Reverse and Forward Direction

PLC based drilling machine

Drilling Process using PLC Program

Car Parking System using PLC Programming

Car Parking System using PLC Programming

HMI

Learn about SCADA and HMI Systems

Learn More

What is Open Telemetry?

What is Open Telemetry? – Principles and Benefits

Luft detector

Luft detector Principle

Radar and Ultrasonic Level Transmitter Problems Troubleshooting

Radar and Ultrasonic Level Transmitter Practical Problems Troubleshooting

Omron PLC Example

Design a Water Pump PLC Program using CX-Programmer

Moving Iron Vane Meter Movement

Moving Iron Vane Meter Movement

Field Instruments enclosures

Pressure Transmitter Heated Enclosures

Digital Electronics Multiple Choice Questions

Design of Combinational Circuits Objective Questions

Nonlinear Control Systems

Stability of Nonlinear System – II

Menu

  • About
  • Privacy Policy
  • Copyright

Quick Links

  • Learn PLC
  • Helping Hand
  • Part Time Job

YouTube Subscribe

Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Welcome Back!

Sign in to your account

Username or Email Address
Password

Lost your password?