How to Design HMI Screen for SCADA Systems Effectively

To design an HMI screen for SCADA, start by defining the process flow and key data points to display. Use clear visuals like buttons, indicators, and graphs with intuitive layout and consistent colors to ensure easy monitoring and control.

Syntax

An HMI screen design typically involves these parts:

• Layout: Organize screen areas for process overview, controls, and alarms.
• Graphics: Use symbols, colors, and animations to represent equipment and status.
• Data Tags: Link screen elements to real-time SCADA data points.
• Navigation: Provide buttons or menus to switch between screens.

xml

<Screen>
  <Layout>
    <Area id="ProcessOverview" />
    <Area id="Controls" />
    <Area id="Alarms" />
  </Layout>
  <Graphics>
    <Pump id="Pump1" statusTag="Pump1_Status" />
    <Valve id="Valve1" statusTag="Valve1_Status" />
  </Graphics>
  <Navigation>
    <Button label="Main" targetScreen="MainScreen" />
  </Navigation>
</Screen>

Example

This example shows a simple HMI screen XML snippet for a SCADA system displaying a pump status and a control button.

xml

<Screen>
  <Layout>
    <Area id="StatusArea" />
    <Area id="ControlArea" />
  </Layout>
  <Graphics>
    <Pump id="Pump1" statusTag="Pump1_Status" colorOn="green" colorOff="red" />
  </Graphics>
  <Controls>
    <Button label="Start Pump" commandTag="Pump1_Start" />
    <Button label="Stop Pump" commandTag="Pump1_Stop" />
  </Controls>
</Screen>

Output

Screen with a pump indicator that turns green when running and red when stopped, plus start and stop buttons.

Common Pitfalls

Common mistakes when designing HMI screens include:

• Overloading the screen with too much information, causing confusion.
• Using inconsistent colors or symbols that users do not understand.
• Not linking graphics correctly to live data tags, resulting in stale or wrong data display.
• Poor navigation that makes switching between screens difficult.

Always test the screen with real users to ensure clarity and usability.

xml

<!-- Wrong: Using red for normal status -->
<Pump id="Pump1" statusTag="Pump1_Status" colorOn="red" colorOff="gray" />

<!-- Right: Green for running, red for fault -->
<Pump id="Pump1" statusTag="Pump1_Status" colorOn="green" colorOff="red" />

Quick Reference

Tips for effective HMI screen design:

• Keep layout simple and logical.
• Use standard colors: green for normal, red for alarms.
• Group related controls and indicators.
• Label all elements clearly.
• Test navigation flow for ease of use.

Key Takeaways

Design HMI screens with clear layout and intuitive navigation for easy monitoring.

Use consistent colors and symbols linked to live SCADA data tags.

Avoid clutter by showing only essential information on each screen.

Test your design with users to ensure it is understandable and usable.