Process Control and Instrumentation — MCQs – EE

1. What is process control?
(A) The regulation of process variables to achieve desired output
(B) The design of electrical circuits
(C) The monitoring of mechanical components
(D) The measurement of power flow

2. The main components of a process control system are:
(A) Sensor, Controller, Actuator, Process
(B) Battery, Load, Switch, Fuse
(C) Motor, Gear, Pulley, Shaft
(D) Amplifier, Speaker, Microphone, Antenna

3. The purpose of an instrumentation system is to:
(A) Measure and control physical quantities
(B) Increase mechanical load
(C) Store electrical energy
(D) Amplify radio signals

4. A transducer converts:
(A) One form of energy into another
(B) Current into voltage
(C) Mechanical load into motion
(D) Pressure into speed

5. The most common controller used in process control is:
(A) PID controller
(B) Relay controller
(C) Differential controller
(D) Magnetic controller

6. In a control system, the setpoint is:
(A) The desired value of the process variable
(B) The actual measured value
(C) The input signal to the actuator
(D) The error signal

7. The process variable is:
(A) The quantity being controlled or measured
(B) The input reference
(C) The actuator’s position
(D) The voltage applied to a motor

8. The error signal in a control system is the difference between:
(A) Setpoint and measured value
(B) Input and output
(C) Process variable and actuator output
(D) Feedback and feedforward

9. Which of the following is an example of a process variable?
(A) Temperature
(B) Color
(C) Speed
(D) Size

10. The function of a sensor is to:
(A) Detect changes in a physical parameter
(B) Control system operation
(C) Provide power to actuators
(D) Store process data

11. A thermocouple is used to measure:
(A) Temperature
(B) Pressure
(C) Flow
(D) Level

12. A strain gauge is used to measure:
(A) Force or pressure
(B) Temperature
(C) Flow rate
(D) Vibration

13. A flow transmitter measures and transmits:
(A) The rate of fluid flow
(B) The level of liquid
(C) The speed of rotation
(D) The position of a valve

14. An actuator in a control system:
(A) Converts control signals into mechanical movement
(B) Measures process variables
(C) Stores data
(D) Generates reference signals

15. The feedback signal in a control system is used to:
(A) Compare the actual output with the desired output
(B) Start the process
(C) Control input voltage
(D) Generate setpoint

16. A closed-loop control system uses:
(A) Feedback
(B) Feedforward only
(C) Manual control
(D) Open signal flow

17. An open-loop control system operates:
(A) Without feedback
(B) With continuous feedback
(C) Based on output correction
(D) Automatically

18. An example of an open-loop system is:
(A) Electric toaster
(B) Air conditioner
(C) Cruise control
(D) Temperature control system

19. An example of a closed-loop system is:
(A) Cruise control system in a car
(B) Washing machine timer
(C) Light switch
(D) Fan regulator

20. The main advantage of a closed-loop system is:
(A) Better accuracy and automatic correction
(B) Lower cost
(C) No need for sensors
(D) Simplicity of design

21. The proportional control in a PID controller:
(A) Provides control output proportional to error
(B) Integrates the error
(C) Differentiates the signal
(D) Delays the output

22. The integral control action in a PID controller:
(A) Eliminates steady-state error
(B) Increases overshoot
(C) Reduces system gain
(D) Increases time delay

23. The derivative control action in a PID controller:
(A) Improves system stability and response
(B) Increases steady-state error
(C) Delays correction
(D) Reduces control signal

24. A manometer is used to measure:
(A) Pressure
(B) Temperature
(C) Level
(D) Flow

25. A level transmitter measures:
(A) Height of liquid or solid material in a vessel
(B) Pressure difference
(C) Flow velocity
(D) Air temperature

26. A pressure sensor outputs a signal proportional to:
(A) The force per unit area applied
(B) Electrical resistance
(C) Capacitance
(D) Voltage level

27. The control valve is an example of a:
(A) Final control element
(B) Measuring device
(C) Signal converter
(D) Transmitter

28. Calibration of instruments ensures:
(A) Accuracy and reliability of measurements
(B) Increased power usage
(C) Lower sensitivity
(D) Mechanical wear

29. In a process control system, dead time refers to:
(A) The delay between input change and process response
(B) The total system operation time
(C) The duration of signal transmission
(D) The shutdown period

30. The main objective of process control and instrumentation is:
(A) Maintain process stability, safety, and efficiency
(B) Reduce automation
(C) Increase human intervention
(D) Control mechanical wear only