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
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: How to Choose a PLC for New Project? – Criteria for Selection of 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
Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Inst Tools > Blog > PLC Tutorials > How to Choose a PLC for New Project? – Criteria for Selection of PLC

How to Choose a PLC for New Project? – Criteria for Selection of PLC

In this article, you will learn how to choose a PLC for the new project and important factors for the selection of PLC, and their criteria.

Last updated: October 17, 2023 1:19 pm
Viral Nagda
PLC Tutorials
No Comments
Share
7 Min Read
SHARE

In this article, you will learn how to choose a PLC for the new project and important factors for the selection of PLC, and their criteria.

Contents
How to Choose a PLC?Criteria for Selection of PLCPower SupplyThe number of Inputs and OutputsCommunication ProtocolEnvironment SpecificationsMotion Requirement / Speed of CPUApplication Requirements of PLCOperator InterfaceAutomation Vendor Support

You are working on an industrial automation project and you will surely require a PLC for that. Many times, we get confused as to what is the right PLC that needs to be chosen for an application.

Because there are many factors involved and ignoring even any one of them will surely cause a hurdle in the performance.

How to Choose a PLC?

How to Choose a PLC

You have set your machine mechanically and electrically; but if you have chosen the wrong PLC for the same, then the design is of no use.

So, it is important to select the right PLC for the application, and for that, it is necessary to understand the various criteria involved in it.

Criteria for Selection of PLC

Let us have a look at the important factors involved in selecting a PLC.

Power Supply

PLC supply can be 24V DC, 24V AC, or 230V AC. Mostly, an electrical panel will have SMPS for the field instrument power supply.

So, depending on the power consumption and SMPS size, you can either use a PLC which requires a 24V DC power supply or a PLC which requires 230V AC.

If you are using a transformer instead which provides 24V AC output, you can choose that PLC which requires a 24 V AC supply. But, just a PLC power supply is not enough.

As discussed, there are field instruments too in the electrical panel; so choose that PLC through which can power it up and also power the instruments according to the voltage required.

Like, if the field devices require DC supply for power, but there is no provision in the PLC IOs for DC supply;  then there is no use in selecting a PLC which has the provision of getting only AC input and output for itself and the IO’s.

So, the power supply is an important factor, and choose the PLC seeing all the angles; not the PLC power supply only.

The number of Inputs and Outputs

Depending on the number of inputs and outputs that you have in the system, choose the PLC accordingly which will support that number.

If even the expansion modules are not enough to fulfill the number, then choose that PLC which supports a higher number of IOs by supporting a higher number of expansion modules.

Nowadays, due to the usage of remote IO PLC, where only IO’s can be connected and no program can be written; more flexibility is provided to the user in choosing the PLC and it also gives him the confidence to go with more numbers of IO’s.

Communication Protocol

Along with PLC, you also have other devices in the panel like a field device that communicates on soft protocol rather than hard protocol (digital IO or analog IO), HMI, SCADA, VFD, and some other type of graphical device.

These devices require networking for communication like Ethernet, Modbus RTU, Device Net, Profibus, Profinet, CAN Open, Modbus ASCII, etc.

So, depending on the device that you are using and the protocol that is used in it, you have to choose the PLC accordingly which will support that protocol.

Environment Specifications

Mostly, PLCs are used in ambient temperature and humidity ranges. But, sometimes, the location can be rugged and there can be chances of extreme temperature or humidity.

So, the PLC used must withstand such changes.

Every PLC comes with operating ranges in its specifications, and it also shows the maximum tolerable ranges that it can withstand.

Motion Requirement / Speed of CPU

High-speed applications require high-speed counters/inputs and high-speed outputs (pulse train type) in PLCs. So, choose the PLC accordingly.

Also, check the processing speed of the CPU (scan time). If it is high, then only it can support such types of fast applications.

Also, motion automation requires customized and special types of software libraries for application; so see whether the PLC chosen has such types of libraries or not.

Application Requirements of PLC

If the application demands some special type of programming and the PLC has dedicated libraries for that, then choose that one.

This will make programming easier, as well as cater to your specific demands in running the machine.

Operator Interface

If the machine operator requires the graphical displays to be operated from the PLC itself, rather than going somewhere long near the HMI for critical operation; then choose the PLC which has an inbuilt display in it.

Although you cannot show every minute graphic representation in that, the operator can at least ensure basic operation of the machine from that; like start, stop or reset buttons.

Automation Vendor Support

The PLC that you are using must be ensured that its manufacturer has a large customer support base, proper pricing, and a strong technical team to support the challenges.

These are the general criteria for selecting a PLC. In this way, we saw some standards which must be taken care of before choosing a PLC.

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

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

Read Next:

  • What is an Air Circuit Breaker?
  • VFD Commissioning Procedure
  • Smart Spray System using PLC
  • Industrial Automation Checklists
  • Career Opportunities in Automation
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

Siemens HMI Training – Using UDTs with Faceplates
CW and CCW Operation of Motor from Same Push button
PLC Cooking Timer Example for Kitchen Automation
PLC Analog Input Conversion Formula
Siemens PLC Tia Portal – OB100 Start-up Organization Block
PLC Example on Switch Program with Timers
Share This Article
Facebook Whatsapp Whatsapp LinkedIn Copy Link
Share
Leave a Comment

Leave a Reply Cancel reply

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

Stay Connected

128.3kFollowersLike
69.1kFollowersFollow
208kSubscribersSubscribe
38kFollowersFollow

Categories

Explore More

PLC Program for Boolean Expression
All About Fieldbus Protocols
Transferring Data Across PLC Systems – TSEND_C and TRCV_C
Delta PLC Counter with Comparison
Sequential Operation of Output Bits using Two Push buttons
Programming and Tuning PID Controller in PLC – Siemens TIA Portal
Transmitters 4-20mA Current Failure Alarm Limits
PLC Automatic Door Control System – Programming Example

Keep Learning

Steps in PLC System Design

Steps in PLC System Design

Door Locking System - PLC Applications Examples

Door Locking System – PLC Applications Examples

Yokogawa DCS Tutorials - Configuration of Analog Input (Transmitter)

Yokogawa DCS Tutorials – Configuration of Analog Input (Transmitter)

DRUM DB

Siemens Drum block for Sequencer Operation

Industrial Gas Detection Systems

PLC based Gas Detection System using Ladder Logic Project

Pumping System in Industrial Automation

Basic Pumping System Application Used in Industrial Automation

PLC Digital Inputs

PLC Digital Input and Digital Output Modules

Pre-Engineering Design Documents

Industrial Automation Pre-Engineering Design Documents – Project & Process

Learn More

Advantages and Disadvantages of Pneumatic Instruments

Advantages and Disadvantages of Pneumatic Instruments

PLC Cooking Timer Example for Kitchen Automation

PLC Cooking Timer Example for Kitchen Automation

Inductive proximity switches

How to Connect Proximity Switch (Sink Type) to Make LED ON ?

Ohm Meter Circuit

Ohm Meter

Electrical Simulator

Free Electrical Circuits Simulator Download

Chromatography Questions & Answers

Chromatography Questions & Answers

Minimum Oil Circuit Breaker (MOCB) Spares & Service

Minimum Oil Circuit Breaker (MOCB) No Vendor Spares & Service

Turbine to Gearbox Alignment Drifts Caused Pump Transfers Problems

Turbine to Gearbox Alignment Drifts Caused Pump Transfers Problems

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?