What is Real-time?
In industrial and technical systems, real-time refers to the ability of a system to respond to an event or input within a predefined and guaranteed time.
So it does not necessarily mean “fast”, but rather within a predictable time limit, however small or large that may be.
🧠 Why does real-time matter?
In industrial environments, processes are often time-critical:
- A motor must stop immediately when a Sensor detects a fault
- A robot arm must grab a product at exactly the right moment
- A control system must cyclically process Sensor data and drive outputs
If the response arrives too late, this can lead to production errors, damage or unsafe situations.
🔧 Types of real-time systems
| Type | Description |
|---|---|
| Hard real-time | Systems where every deadline absolutely must be met. |
| e.g.: safety systems, Motion Control. | |
| Soft real-time | Deadlines are important, but occasional lateness is acceptable. |
| e.g.: HMI updates, video streaming. | |
| Non real-time | There is no guarantee of timeliness. |
| e.g.: email, administration, ERP. |
🏭 Examples in industrial automation
| Application | Type of real-time | Explanation |
|---|---|---|
| PLC motor control | Hard real-time | Must switch at exactly the right moment |
| HMI visualisation | Soft real-time | A small delay is acceptable |
| Historian data logging | Soft real-time | A small delay or buffer time is acceptable |
| ERP system | Non real-time | Planning data does not need immediate processing |
🔄 Real-time vs. fast
Real-time does not always mean “faster” than other systems. It means: always on time, regardless of whether that is 1 millisecond or 1 second — as long as it is predictable.
📌 In summary
Real-time systems respond within a predetermined time, with predictability and reliability. In industrial automation, this is crucial for guaranteeing safety, quality and performance.