Que Bank-B PDF

Unit 3 1. What is the main purpose of a control system? A) To amplify signals B) To process data C) To maintain a desired output D) To generate random values 2. What does the term "error" refer to in control systems? A) The difference be...

Unit 3 1. What is the main purpose of a control system? A) To amplify signals B) To process data C) To maintain a desired output D) To generate random values 2. What does the term "error" refer to in control systems? A) The difference between the desired and actual output B) The maximum value of the output C) The time taken to reach the output D) The input to the system 3. What is a variable range in the context of control systems? A) The range of possible inputs B) The range of possible errors C) The range of possible outputs D) The range of control actions 4. What does "cycling" in a control system imply? A) Continuous increase in output B) Periodic oscillation of output C) Gradual decrease in output D) Random changes in output 5. What is "direct action" in a control system? A) Increase in controller output with increase in error B) Decrease in controller output with increase in error C) No change in controller output D) Fluctuation of controller output 6. Which of the following is a characteristic of a two-position control mode? A) Continuous control B) Multiple output levels C) On/Off control D) Proportional control 7. What is a multi-position control mode? A) It has only two positions: on and off B) It has multiple discrete positions C) It continuously adjusts the output D) It uses proportional control 8. In floating control mode, the controller output: A) Changes in fixed steps B) Moves to discrete positions C) Varies continuously within a range D) Remains constant 9. Proportional control mode adjusts the controller output: A) Proportional to the error B) Proportional to the rate of change of error C) Based on the integral of the error D) In fixed steps 10. Integral control mode is primarily used to: A) Eliminate steady-state error B) Reduce oscillations C) Increase the system's speed D) Reduce noise 11. What is the primary purpose of derivative control mode? A) To eliminate steady-state error B) To predict future error C) To respond to the rate of change of error  D) To reduce the noise in the system 12. A Proportional-Integral (PI) controller is used to: A) Eliminate steady-state error and dampen oscillations B) Only eliminate steady-state error C) Only dampen oscillations D) None of the above 13. What is the function of a Proportional-Derivative (PD) controller? A) To eliminate steady-state error B) To improve transient response C) To provide integral action D) To act as an On/Off controller 14. A PID controller combines which of the following actions? A) Proportional and Integral B) Proportional and Derivative C) Proportional, Integral, and Derivative D) Integral and Derivative 15. What is "reset windup" in a PID controller? A) A condition where the derivative action dominates B) A condition where the integral action accumulates excessively  C) A state where proportional control fails D) A failure in the controller reset mechanism 16. "Rate before reset" in a PID controller refers to: A) Derivative action applied before integral action B) Integral action applied before proportional action C) Resetting the controller at a constant rate D) None of the above 17. What does "bump less transfer" ensure in a control system? A) Sudden changes in output when switching controllers B) Smooth transition without sudden output changes C) Continuous oscillations during transfer D) Discontinuous control actions 18. Which control mode is typically used to eliminate steady-state error? A) Proportional B) Integral C) Derivative D) Floating 19. When is derivative control most useful?  A) When fast response is needed B) When steady-state error needs to be minimized C) When the system is highly noisy D) When the system is very slow 20. Which of the following is NOT a type of discontinuous control mode? A) Two-position control B) Multi-position control C) Floating control D) Proportional control Unit 4 1. What is the main goal of tuning a PID controller? A) To simplify the control system B) To optimize the controller parameters for desired performance C) To reduce the complexity of the controller D) To eliminate the need for feedback 2. Which of the following is NOT a common performance criterion for tuning PID controllers? A) Quarter amplitude decay ratio B) Integral time performance indices C) Zero-crossing rate D) Minimum settling time 3. What does the "Quarter amplitude decay ratio" criterion imply? A) The amplitude of oscillations should double with each cycle B) The amplitude of oscillations should reduce by a quarter with each cycle C) The amplitude of oscillations should remain constant D) The amplitude of oscillations should reduce to a quarter of the initial value 4. Which performance index considers the cumulative error over time? A) Integral of the absolute error (IAE) B) Integral of the squared error (ISE) C) Integral of the time-weighted absolute error (ITAE) D) All of the above 5. Which performance index gives more weight to errors that occur later in the process? A) Integral of the absolute error (IAE) B) Integral of the squared error (ISE) C) Integral of the time-weighted absolute error (ITAE) D) Proportional control index (PCI) 6. What is the Integral of the Squared Error (ISE) used for? A) Minimizing the time to reach the setpoint B) Penalizing larger errors more than smaller ones C) Balancing proportional and derivative actions D) Reducing the steady-state error 7. What is the Process Reaction Curve method also known as? A) Closed-loop tuning B) Open-loop tuning C) Feedback tuning D) Direct tuning 8. In the Process Reaction Curve method, what is typically observed to derive tuning parameters? A) The system's frequency response B) The system's transient response to a step input C) The system's steady-state response D) The system's noise characteristics 9. Which of the following is NOT a step in the Process Reaction Curve method? A) Apply a step input to the system B) Record the output response C) Calculate the process gain, time constant, and dead time D) Directly adjust PID parameters based on system noise 10. What is the main objective of the Ziegler-Nichols tuning method? A) To find the exact mathematical model of the system B) To determine PID parameters that yield a desirable closed-loop response C) To minimize the cost of the controller D) To eliminate the need for manual tuning 11. In the Ziegler-Nichols closed-loop method, what is the ultimate gain (Ku)? A) The gain at which the system starts to oscillate B) The maximum possible gain of the system C) The gain at which the system output is zero D) The gain at which the system reaches steady-state 12. What is the ultimate period (Pu) in the Ziegler-Nichols method? A) The time it takes for the system to reach the setpoint B) The period of oscillation at the ultimate gain C) The time constant of the system D) The settling time of the system 13. According to Ziegler-Nichols, how are the PID parameters set once Ku and Pu are determined? A) Using pre-determined formulas based on Ku and Pu B) By trial and error C) By minimizing the integral of the absolute error D) By using the process reaction curve method 14. Which of the following is a characteristic of the Ziegler-Nichols tuning method? A) It provides exact optimal tuning B) It often results in a conservative (slow) response C) It is a heuristic method providing good starting values D) It is used exclusively for integral control 15. For which type of control is the Ziegler-Nichols method particularly useful? A) Proportional control only B) Proportional-Derivative control only C) Proportional-Integral-Derivative control D) Integral-Derivative control only 16. What is a limitation of the Ziegler-Nichols tuning method? A) It can be applied only to linear systems B) It does not provide any initial guess for tuning parameters C) It can result in excessive oscillations in some systems D) It is too complex for practical use 17. Why might an engineer prefer the Process Reaction Curve method over Ziegler-Nichols? A) It provides more conservative tuning parameters B) It is easier to implement for nonlinear systems C) It directly measures system frequency response D) It does not require inducing oscillations in the system 18. What kind of system behavior does the Quarter Amplitude Decay Ratio aim to achieve? A) Rapidly decaying oscillations B) Slow response to setpoint changes C) Consistent amplitude of oscillations D) No oscillations at all 19. When using the Process Reaction Curve method, what is the significance of the process gain (Kp)? A) It determines how much the process variable changes in response to a change in the controller output B) It represents the speed of the process response C) It measures the delay in the process response D) It is unrelated to the step input response 20. What is the typical first step in the Process Reaction Curve method? A) Measuring the process noise B) Applying a disturbance to the system C) Applying a step input to the system D) Setting initial PID parameters Unit 5 1. What is the primary function of a current-to-pressure (I/P) converter? A) To convert electrical signals to pneumatic signals B) To convert pneumatic signals to electrical signals C) To measure fluid flow D) To control valve position 2. What does a pressure-to-current (P/I) converter do? A) Converts pressure signals to electrical signals B) Converts electrical signals to pressure signals C) Measures fluid viscosity D) Controls actuator speed 3. Why are final control elements necessary in a control system? A) To provide feedback signals B) To convert signals between different forms C) To directly regulate the flow of energy or material D) To measure system output 4. Which part of a control valve is responsible for regulating fluid flow? A) Actuator B) Valve body C) Positioner D) Handwheel  5. What type of actuator uses air pressure to operate a control valve? A) Electric actuator B) Pneumatic actuator C) Hydraulic actuator D) Manual actuator 6. Which actuator type provides the highest force for valve operation? A) Pneumatic actuator B) Electric actuator C) Hydraulic actuator D) Handwheel actuator 7. What is a common use for a handwheel actuator? A) To automatically control valve position B) To manually override automatic control C) To measure fluid flow D) To convert pressure to current 8. How are control valves typically classified? A) By the type of fluid they control B) By their method of operation C) By their size D) By their installation method 9. What does "rangeability" refer to in control valves? A) The ratio of maximum to minimum controllable flow rate B) The speed at which the valve can open or close C) The maximum pressure the valve can handle D) The temperature range the valve can operate in 10. What is "turndown" in the context of control valves? A) The ability of the valve to operate at low flow rates B) The ratio of maximum capacity to minimum controllable flow C) The time taken for the valve to fully open D) The pressure drop across the valve 11. Which term refers to the ability of a control valve to handle fluids of varying viscosities? A) Rangeability B) Turndown C) Viscosity index D) Valve capacity 12. What is valve capacity usually measured in? A) Liters per second (L/s) B) Gallons per minute (GPM) C) Pounds per square inch (PSI) D) Kilograms per hour (kg/h) 13. In control valve terminology, what does AO stand for? A) Air to Open B) Automatic Operation C) Actuator Opening D) Adjustable Output 14. What does AC stand for in control valve terminology? A) Air to Close B) Automatic Control C) Actuator Control D) Adjustable Capacity 15. What is a "fail-safe action" in control valves? A) The default action a valve takes upon loss of control signal B) The maximum pressure the valve can withstand C) The ability to operate at low temperatures D) The speed at which the valve closes 16. What are inherent control valve characteristics? A) The valve's behavior when installed in a system B) The valve's behavior when operating without external influences C) The valve's maximum capacity D) The valve's temperature range 17. What are installed control valve characteristics? A) The valve's theoretical performance B) The valve's behavior in the actual process system C) The valve's response time D) The valve's maximum pressure rating 18. What does the control valve sizing coefficient Cv represent? A) The valve's ability to control flow rate B) The flow rate through the valve at a specified pressure drop C) The valve's maximum operating pressure D) The temperature range the valve can handle 19. Cv is typically defined as the flow rate in gallons per minute (GPM) that a valve can pass for a pressure drop of: A) 1 PSI B) 10 PSI C) 100 PSI D) 0.1 PSI 20. Which of the following factors affect the Cv of a control valve? A) Valve size and type B) Fluid viscosity and density C) Valve opening position D) All of the above Unit 6 1. What is the main construction feature of a globe valve? A) Spherical body with a disc B) Rotating ball with a hole C) A gate that slides up and down D) A butterfly disc 2. What is one advantage of using a globe valve? A) High flow capacity B) Excellent throttling capability C) Minimal pressure drop D) Simple construction 3. Which of the following is a disadvantage of a globe valve? A) Poor throttling ability B) High pressure drop C) Not suitable for high temperatures D) Difficult to maintain 4. In what applications are single-seated globe valves typically used? A) High flow applications B) Applications requiring tight shutoff C) Low-pressure systems D) Applications with minimal pressure drop  5. What is the main difference between a single-seated and double-seated globe valve? A) The number of actuators B) The number of plugs and seats C) The type of fluid they control D) The direction of flow 6. In what scenario would a double-seated globe valve be preferred? A) Where tight shutoff is critical B) Where balanced forces on the valve stem are needed C) For applications requiring minimal maintenance D) For highly viscous fluids 7. What is a unique feature of a 3-way globe valve? A) It can only be used in mixing applications B) It has three ports for fluid flow C) It operates only in on/off mode D) It is not used for throttling 8. Which of the following is an advantage of gate valves? A) Excellent throttling capability B) Low pressure drop when fully open C) Compact size D) Fast operation  9. What is a typical application for angle valves? A) For straight-line fluid flow B) For 90-degree flow direction changes C) For high-speed actuation D) For high-temperature applications 10. What is the main advantage of a butterfly valve? A) Excellent throttling capability B) Compact and lightweight design C) High pressure drop D) Complex construction 11. In what applications are ball valves typically used? A) Applications requiring precise throttling B) On/off applications with minimal pressure drop C) High-temperature applications D) Applications with significant pressure drops 12. Which characteristic is typical of a ball valve? A) Spherical disc with a hole B) Flat gate that slides up and down C) Rotating disc in the shape of a butterfly D) Spherical body with a disc  13. What is the primary need for a positioner in a control valve system? A) To increase the valve size B) To ensure the valve reaches the desired position accurately C) To reduce noise D) To convert current to pressure 14. How does a positioner affect the performance of a control valve? A) Reduces valve response time B) Improves the precision of valve positioning C) Decreases the overall system efficiency D) Increases the likelihood of cavitation 15. What is cavitation in control valves? A) Formation and collapse of vapor bubbles in the fluid B) Continuous flow of liquid C) High-frequency noise generation D) A smooth fluid flow 16. Which of the following is a common remedy for cavitation? A) Increasing fluid temperature B) Reducing the valve size C) Using a valve with anti-cavitation trims D) Increasing the flow rate  17. What is flashing in a control valve? A) Conversion of liquid to gas and remaining as gas downstream B) Conversion of gas to liquid C) Formation of ice crystals in the fluid D) Generation of electrical signals 18. How can flashing be mitigated in control valves? A) Reducing the downstream pressure B) Increasing the upstream pressure C) Using a valve with special trims or selecting materials that can handle flashing conditions D) Reducing the fluid temperature 19. What effect does noise have on control valve systems? A) Improves system efficiency B) Reduces the life span of valve components C) Has no impact on the system D) Increases flow rate 20. Which method is effective in reducing noise in control valves? A) Increasing the flow velocity B) Using noise attenuating trims or silencers C) Reducing the valve size D) Increasing the pressure drop across the valve