SCADA vs. HMI: Key Differences and Their Role in Industry 4.0

The interaction between machines and humans is part of Industry 4.0. As a result of this relationship between workers and robotics, terms and systems such as SCADA and HMI have emerged.  These two concepts often go together when we talk about Industry 4.0. However, both have their differences and similarities.

Before knowing what the differences are between a SCADA and an HMI, it is important to point out what these two systems consist in. First of all, both a SCADA and an HMI are industrial control systems and both technologies are used in the automation industry.

 

What is an HMI system?

An HMI (Human Machine Interface) system is a user interface that allows a machine to connect with a human. HMI systems improve communication between machines and operators, optimising tasks and allowing them to be executed more quickly.

In short, an HMI is a control station for the user. Typically, it has a monitor or display linked to a machine and its production process. HMIs are linked to a controller and are installed very close to the machines. Some sensors can even be programmed to a monitor themselves on the same screen.

These operator panels help connect to the equipment to:

• View information and monitor production processes.
• Enter the information needed to operate properly
• Control the mechanisms that are part of the production chain
• View alarms and permissions

 

What is a SCADA?

SCADA systems refer to the acronym “Supervisory Control and Data Acquisition”. They are used to monitor and control large areas, e.g. an entire production plant, in real time.

In addition, SCADA systems combine many systems such as sensors, PLCs or RTU sensors. The data collected by all these systems is sent to the central SCADA unit, which will have its own HMI.

The purpose of SCADA systems is to diagnose errors, manage production and improve a company’s processes.

SCADA systems store a large amount of information and allow several people to operate on the same system simultaneously.

These are some of the functions of a SCADA system:

• Control systems through HMI software.
• Monitor and control production processes and complete plant operations in real time.
• Collect any kind of valuable data.
• Generate practical, real-time operating reports
• Automate processes, such as control of machinery energy consumption, production peaks, maintenance, etc.

 

 

Are SCADA and HMI complementary concepts?

Actually, SCADA and HMI technologies are different and can complement each other without any problem. In fact, they are often used together to create a functional and very useful industrial tool.

SCADA systems are essential when it is about large industrial production infrastructures. An HMI system, on the other hand, is the very technology that will help carry out the monitoring in a SCADA system.

This means that a SCADA system needs an HMI technology to be able to visualise all the information related to the production chain.

The SCADA unit has its own HMI. That is why many people get confused and think that SCADA and HMI are the same.

That HMI or “Human Machine Interface” unit in the SCADA can supervise and control anything that is connected to it. In conclusion, the HMI can be part of the SCADA, but the SCADA cannot be part of an HMI.

 

Nexus Integra and its Smart SCADA application

Nexus Integra is the open and standard industrial system integration platform, capable of generating a global operations and monitoring environment for the management of large-scale industrial assets.

With this platform you can acquire data from any source (databases, OPCs, SCADA systems, etc). In addition, Nexus Integra has a series of native tools, including its Smart SCADA application that allows you to create a centralised operating environment to manage all the geographically dispersed assets of a company.

Looking for the best solution to implement a monitoring, control and data acquisition system? Contact us and let’s talk about how Nexus Integra can help your company.