What is Trending?
Trending is the graphical display of process values over time within industrial automation. It helps operators, engineers and maintenance teams see how a system or value is developing, recognise patterns and detect deviations.
Trending is usually carried out in SCADA or HMI systems, or with the help of a Historian.
📈 What is trending used for?
- Fault analysis: What was happening just before an alarm?
- Quality control: Have process conditions stayed within tolerances?
- Optimisation: See how adjustments affect production
- Predictive Maintenance: Analyse trend lines for vibration or temperature
- Comparison with Setpoints: How closely does the system follow the desired value?
🔍 Types of trending
| Type | Description |
|---|---|
| Live trending | Real-time graphs of current measurement values |
| Historical | Looking back at stored data via Historian |
| Overlays | Multiple time periods overlaid for comparison |
| Multivariable | Several Tags at once (e.g. pressure, temperature, flow) |
🏭 Example
In a furnace control:
-
The Tag
Oven1.Tempis logged every second - SCADA displays a trend graph over the last 24 hours
- The operator sees that the temperature spiked outside the Setpoint limit two hours ago
- Maintenance is scheduled based on that deviation
📌 In summary
Trending is the visual analysis of process data over time, essential for Monitoring, troubleshooting, optimisation and maintenance in industrial environments.