HMI (Human Machine Interface) Design — MCQs – EE

1. The term HMI stands for:
(A) Human Machine Integration
(B) Human Machine Interface
(C) Hardware Monitoring Interface
(D) Human Monitoring Instrument

2. The main purpose of an HMI in industrial automation is to:
(A) Allow operators to monitor and control processes visually
(B) Store backup data only
(C) Replace PLCs in control systems
(D) Transmit power to sensors

3. The HMI is typically connected to:
(A) PLCs or SCADA systems
(B) Motors directly
(C) Electric generators
(D) Batteries only

4. The primary function of an HMI screen is to:
(A) Display process data and alarms in real time
(B) Generate analog signals
(C) Transmit wireless communication
(D) Control power supply

5. Touchscreen panels are commonly used in HMI systems to:
(A) Simplify operator input and control
(B) Increase circuit resistance
(C) Control data flow in networks
(D) Replace sensors

6. A well-designed HMI layout should be:
(A) Simple, intuitive, and user-friendly
(B) Complex with multiple colors
(C) Hidden from the operator
(D) Text-only with no visuals

7. The graphical display in HMI typically shows:
(A) Process diagrams, parameters, and control buttons
(B) Source code of the PLC
(C) Hardware schematics only
(D) Device serial numbers

8. Color coding in HMI design helps to:
(A) Differentiate between normal and alarm states
(B) Make screens more decorative
(C) Reduce brightness only
(D) Identify communication errors

9. The alarm window in HMI is used to:
(A) Notify operators about abnormal conditions
(B) Store backup data
(C) Control actuators directly
(D) Reset PLC programs

10. The trending feature in HMI displays:
(A) Process variable changes over time
(B) PLC scan time
(C) Communication errors
(D) Memory usage

11. Real-time data monitoring in HMI is important for:
(A) Immediate decision-making and control actions
(B) Historical data backup only
(C) Software licensing
(D) Displaying startup screens

12. A tag in HMI programming represents:
(A) A variable linked to a PLC memory address
(B) A color scheme
(C) A system warning
(D) A communication cable

13. Screen navigation in HMI design allows:
(A) Operators to move between different process displays
(B) PLCs to store more data
(C) Motors to start automatically
(D) Alarms to reset

14. The HMI designer software is used to:
(A) Create and configure graphical user interfaces
(B) Compile PLC logic
(C) Design mechanical parts
(D) Calibrate sensors

15. In an HMI, the setpoint input field is used for:
(A) Adjusting process parameters
(B) Viewing alarm history
(C) Accessing control logic
(D) Restarting the system

16. The security feature in HMI design ensures:
(A) Only authorized users can access control screens
(B) All alarms are disabled
(C) The display runs offline
(D) Touch inputs are blocked

17. Password protection in HMIs is used to:
(A) Restrict unauthorized parameter changes
(B) Reduce power consumption
(C) Control color brightness
(D) Disable alarms

18. The data logging function in HMI helps in:
(A) Recording process values for analysis
(B) Controlling power output
(C) Generating mechanical motion
(D) Managing communication errors

19. The HMI communication driver is used to:
(A) Interface HMI with specific PLC models
(B) Monitor user activity
(C) Control system power
(D) Store HMI configurations

20. A dynamic object in HMI refers to:
(A) A graphical element that changes with process variables
(B) A fixed background image
(C) A static label
(D) A color palette

21. The trend chart in HMI helps operators:
(A) Analyze variations in process data
(B) Adjust communication protocols
(C) Configure PLC scan cycles
(D) Reduce alarm frequency

22. Pop-up screens in HMI are used to:
(A) Display alerts or quick control options
(B) Hide user inputs
(C) Show advertisements
(D) Manage file storage

23. The HMI runtime mode allows:
(A) Real-time display and control operation
(B) Design editing
(C) Code compilation
(D) Firmware installation

24. A multi-level HMI interface is useful in:
(A) Large systems with multiple process areas
(B) Simple single-loop controls only
(C) Power circuits only
(D) Manual machinery

25. The trend cursor feature in HMI helps:
(A) Identify exact data values on trend charts
(B) Switch between communication modes
(C) Adjust PLC cycle time
(D) Reset alarms

26. The alarm acknowledgment function in HMI allows:
(A) Operators to confirm awareness of an alarm condition
(B) Automatic alarm deactivation
(C) Disabling the alarm system
(D) Resetting PLC memory

27. A symbol library in HMI software provides:
(A) Predefined graphical icons and animations
(B) Alarm lists
(C) PLC communication addresses
(D) Control logic routines

28. The HMI color palette should be chosen to:
(A) Improve visibility and reduce operator fatigue
(B) Add decorative effects
(C) Use all available colors
(D) Change alarm behavior

29. The trend archive in an HMI stores:
(A) Historical trend data for analysis
(B) Alarm messages only
(C) Communication logs
(D) User passwords

30. The benefit of good HMI design is:
(A) Improved operator efficiency and reduced human error
(B) Increased system complexity
(C) Slower control response
(D) Reduced automation level