fbpx

What is Remote I/O?

In this article, we’re going to explain the terms I/O, Local I/O, and Remote I/O, and why Remote PLC I/O is used in industrial applications.

In the industrial control world, we use the term I/O often. So, let’s begin our discussion today with an explanation of I/O. The focus of our discussion will be on Remote I/O, but we’re also going to talk about Local I/O too.

In this article, we’re going to:

– Explain the terms I/O, Local I/O, and Remote I/O

– Explain why Remote I/O is used in industrial applications

– List 2 transmission mediums used to connect between the local PLC and the Remote I/O

– List 2 transmission protocols used to communicate between the local PLC and the Remote I/O

What I/O Refers to in the Industrial World?

I/O stands for Input/Output.

In the industrial world, I/O refers to any device that transfers data to or from a computer such as a PLC.

For our discussion, we’ll refer to these I/O devices as I/O Modules.

Field Devices such as sensors and actuators are connected to the I/O modules.

The sensor signal representing a process variable such as liquid flow is converted by an Input I/O module and stored in the PLC memory.

The actuator receives an operating signal from an Output I/O module.

Local I/O VS Remote I/O

Local I/O refers to I/O modules that are housed in the same cabinet and likely connected to the controller backplane in the PLC rack.

Remote I/O simply means that the I/O module is at a remote place physically located a distance from the control PLC.

A remote I/O module will speak to the PLC via an Adaptor Module connected to the controller backplane in the PLC rack.

Why Do We Use Remote I/O?

There are several reasons…. let’s look at a few.

1) When it’s not possible to have a PLC near the field devices

In some industrial applications, it’s not possible to have a PLC with Local I/O Modules near the field devices because of the harsh environment.

2) You want to eliminate long lengths of multi-conductor cable

Remote I/O is a solution when you want to place I/O modules close to the field devices in order to eliminate long lengths of multi-conductor cable.

With Remote I/O, signals can be received from far away sensors and control signals can be sent long distances to control valves, motors, and other final actuators.

Remote I/O Transmission Protocols 

Signals can be sent any distance on a high-speed medium such as twisted-pair wires and fiber optics using a variety of transmission protocols such as Ethernet and Profibus.

Summary

Let’s review what we’ve discussed.

– I/O stands for Input/Output

– I/O refers to any device that transfers data to or from a computer such as a PLC

– Field Devices such as sensors and actuators are connected to the I/O modules

– Local I/O refers to I/O modules connected to the controller backplane in the PLC rack

– A remote I/O module is physically located at a distance from the control PLC

Remote I/O’s are used:

– Because in some industrial applications, it’s not possible to have a PLC with Local I/O Modules near the field devices because of the harsh environment.

– When you want to place I/O modules close to the field devices to eliminate long lengths of multi-conductor cable

– Signals can be received from far away sensors and final actuators

– Signals can be sent any distance with a high-speed medium such as twisted-pair wires and fiber optics using a variety of transmission protocols such as Ethernet and Profibus

Want to Learn More?

You can gain instant access to a large number of exclusive RealPars courses covering a variety of industrial automation topics, including PLC and HMI programming, DCS, IIoT, and others, all for a small yearly membership fee.

It’s an amazing value for some really robust content and lots of support. And you’ll be getting the same course work that would cost you a few thousand for one week of offline training!

All of us on the RealPars team look forward to helping you continue to advance your PLC expertise and your career! 

Got a friend, client, or colleague who could use some of this information? Please share this article.

The RealPars Team
By Ted Mortenson

By Ted Mortenson

Automation Engineer

Posted on Apr 13, 2020

By Ted Mortenson

Automation Engineer

Posted on Apr 13, 2020

5 Actionable Tips for Getting a PLC Programming Job with NO Experience

5 Actionable Tips for Getting a PLC Programming Job with NO Experience

In this blog post, you’ll learn about the mindset that helped me getting a PLC programming job with NO experience. This is my personal experience as someone who searched for a job in this field and as an employer who reviews resumes and interviews candidates for a variety of projects. So let’s get started!

A First Look at the Low-Code Future of PLC Programming

A First Look at the Low-Code Future of PLC Programming

At RealPars, we focus on teaching automation engineers, controls engineers, and technicians the skills that they need to be successful in their careers both now and in the future. We are constantly collaborating with manufacturers to understand what the future of...

Omron Sysmac Studio 3D Simulation Visualization

Omron Sysmac Studio 3D Simulation Visualization

 In this article, you're going to learn how to use Omron Sysmac Studio 3D simulation function for your robatic applications. The 3D function is easily added to Sysmac Studio by way of a license from OMRON. We’ll give you more details on that later.Simulation of a...

RealPars is the world's largest online learning platform for cutting-edge industrial technologies. 

Questions?
[email protected]
+31 10 316 6400
Mon - Fri  8:30 am to 5:30 pm (CET)

Rotterdam Science Tower,
Marconistraat 16,
3029AK Rotterdam, The Netherlands

COMPANY

About

Job openings

Privacy

Cookies

LEARN

Courses

Blog

Sign in

HELP

Contact Us

Help & Support

Refund & Cancellation Policy

© 2022 RealPars B.V. All rights reserved.

Created with coffee and tea in Rotterdam.