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Adding IoT capability to existing systems part 1


With a few simple additions you can bring existing legacy products into the IoT environment. 

In this part 1 post, we show how using Brainboxes remote IO modules can add Ethernet connectivity to installed systems. This will allow the release of data from old and existing machines, thus increasing control options and improving productivity in legacy systems.

There is no need to invest in expensive upgrades to get the best out of your systems, here we show how incorporating remote IO modules from Brainboxes is an effective solution for a simple upgrade of installed systems.

The devices used here are: an Ethernet to Digital IO with RS232 Serial unit ED-204 (789-8141) , an Ethernet to 16 Digital Out unit ED-527 (789-8122) and an Ethernet Switch SW-504 (847-4752) .

SW-504 Ethernet Switch


The SW-504 switch allows all the equipment to be connected to the network. On the demo board we have connected the PLC, HMI, ED-204 and ED-527 to the SW-504 Ethernet Switch, this allows all the equipment to become a connected network. This switch is what is known as an unmanaged switch and requires no software, it just simply gives more Ethernet ports to get everything connected up.

Once equipment is connected to the network you are free from the physical proximity of wiring constraints. You can monitor and control from a convenient central location and even keep tabs on your production line on the go.

Remote IO demo board


I/O units can be located away from the PLC, these are referred to as Remote I/O or Distributed I/O and that’s what we have here with the ED-204 and the ED-527. Ethernet based Remote I/O is an effective way to extend or expand your control and monitoring capability across a wide area. For more information on setting up remote IO please see link below

Demo board video

The video below shows how to connect common types of factory devices, extract their data and control them. This can be really useful for modernising, automating and ultimately making your factory more efficient. This forms the bases of the IoT or Industry 4.0 movements, which is what we will focus more on in part 2.

Setup overview

To simplify set up all the devices have a fixed IP address. So once you have everything plugged into the network you can go into the Schneider Electric M221 PLC (846-4695) or the Magelis HMI and locate the devices you need to talk to. There is information provided in the Brainboxes product manuals that can help you do this.

Brainboxes ED-204 and ED-527 come with Modbus TCP so they are ready to talk to the Schneider devices as soon as you tell them to use this language. Once you have configured the devices you can set the PLC and HMI to talk to them using Modbus TCP. This protocol is a selected option within the Schneider Electric software.

In the demo board example we can now control the fan from either the HMI or by pressing the stop start buttons. This principal can also be used for a number of industrial applications, such as; machine shut down if a safety door is opened. 


Brainboxes Ethernet to Digital IO can be used to monitor inputs such as sensors and switches, as shown on the ED-204. They can also be used to control remote outputs such as fans, buzzers and displays as shown through the ED-527 Ethernet to 16 output device.

With these products you can:

• Know how many events have occurred
• Know immediately if there is a breakdown
• Know that your machine is making money in real time.
• Knowing how long your machine is up and running for helps you calculate your machine’s Overall Equipment Effectiveness.
• This data can then be used as hard evidence to review future capital investment decisions.

Using the touchscreen menu on the HMI, you can see what sensors and outputs are doing in real-time and also see the count of how many times the buttons or sensors have changed status. At the end of the day, week or month, all information can be reviewed to work out system performance.

Schneider Electric Reference

Both the PLC and HMI are programmed using Vijeo (HMI design) and SoMachine (PLC Ladder Logic) software tools from Schneider.  

Vijeo HMI Design

Schneider Electric HMI Software (907-6491)


Schneider Electric PLC Software (815-0667)

In part 2 we will focus more on bridging the gap between legacy systems and the Internet of Things

Related articles

For more on Legacy to IoT

More on Brainboxes network

SoMachine PLC Ladder Logic


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