Industrial Electronics — MCQs – EE

1. What is Industrial Electronics mainly concerned with?
(A) Application of electronics in control and automation of industrial systems
(B) Communication engineering
(C) Computer networking
(D) Power generation only

2. Which of the following is a typical component in industrial control systems?
(A) Programmable Logic Controller (PLC)
(B) Bluetooth module
(C) Microphone
(D) Loudspeaker

3. The main function of a PLC is to:
(A) Automate industrial machines and processes
(B) Store digital media
(C) Amplify audio signals
(D) Display data

4. Which device converts AC to DC in industrial applications?
(A) Rectifier
(B) Inverter
(C) Transformer
(D) Regulator

5. An inverter in industrial electronics is used to:
(A) Convert DC to AC
(B) Convert AC to DC
(C) Store energy
(D) Control sensors

6. Which of the following is used for speed control of DC motors?
(A) Chopper
(B) Transformer
(C) Oscillator
(D) Relay

7. An SCR (Silicon Controlled Rectifier) is commonly used in:
(A) Power control applications
(B) Data communication
(C) Audio amplification
(D) Signal detection

8. A triac is primarily used for:
(A) AC power control
(B) DC voltage regulation
(C) Signal filtering
(D) Voltage measurement

9. A diac is commonly used with:
(A) Triac triggering circuits
(B) Transformers
(C) Capacitors
(D) Sensors

10. Which device is used for converting DC to variable DC voltage?
(A) DC Chopper
(B) Rectifier
(C) Inverter
(D) Amplifier

11. Which of the following components provides electrical isolation between control and power circuits?
(A) Optocoupler
(B) Capacitor
(C) Diode
(D) Fuse

12. A VFD (Variable Frequency Drive) is used to:
(A) Control speed of AC motors
(B) Rectify AC to DC
(C) Measure voltage
(D) Stabilize current

13. Which semiconductor device can control both current and voltage?
(A) Power MOSFET
(B) Diode
(C) Resistor
(D) Inductor

14. Industrial automation often relies on:
(A) Sensors and actuators
(B) Manual switches
(C) Transistors only
(D) CRT displays

15. A servo drive is used to:
(A) Control position, speed, and torque of servo motors
(B) Convert AC to DC
(C) Filter analog signals
(D) Store data

16. The main function of a power supply unit (PSU) in industrial equipment is to:
(A) Provide regulated voltage to circuits
(B) Control motor speed
(C) Amplify current signals
(D) Transmit data

17. Which of the following is used for overcurrent protection?
(A) Circuit breaker
(B) Transformer
(C) Oscillator
(D) Transistor

18. In industrial control, SCADA stands for:
(A) Supervisory Control and Data Acquisition
(B) Serial Control and Data Access
(C) System Communication and Device Application
(D) Signal Communication and Drive Automation

19. A PID controller is used to:
(A) Maintain process variables like temperature, pressure, or speed
(B) Convert power from AC to DC
(C) Amplify signals
(D) Store control data

20. Industrial relays are used to:
(A) Switch high power loads
(B) Store energy
(C) Measure current
(D) Amplify voltage

21. Which type of sensor is used for detecting proximity of metal objects?
(A) Inductive sensor
(B) Capacitive sensor
(C) Optical sensor
(D) Thermal sensor

22. In an industrial environment, noise immunity can be improved by using:
(A) Opto-isolation and shielding
(B) Higher voltage signals
(C) Open wiring
(D) Parallel communication

23. A relay driver circuit is usually built using:
(A) Transistor or MOSFET
(B) Capacitor
(C) Diode
(D) Resistor

24. Which of the following devices is used for power factor correction?
(A) Capacitor bank
(B) Diode bridge
(C) Rectifier
(D) Transformer

25. The H-bridge circuit is commonly used for:
(A) Controlling motor direction
(B) Voltage regulation
(C) Temperature sensing
(D) Current measurement

26. Industrial automation systems primarily aim to:
(A) Increase productivity and reduce human intervention
(B) Replace all electrical systems
(C) Increase manual operation
(D) Reduce network communication

27. Which power electronic device is suitable for high-speed switching?
(A) IGBT
(B) Diode
(C) BJT
(D) LDR

28. A snubber circuit is used to:
(A) Protect switching devices from voltage spikes
(B) Amplify AC signals
(C) Store energy temporarily
(D) Increase current flow

29. The main advantage of industrial automation using PLCs is:
(A) High reliability and easy reprogramming
(B) High manual effort
(C) Low speed
(D) No expandability

30. Which communication protocol is commonly used in industrial control networks?
(A) Modbus
(B) HTTP
(C) Bluetooth
(D) POP3