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WorksheetsAUTO 1 LEC MIDTERM QUIZ 1
Total questions: 20
Worksheet time: 15mins
Which control mode operates without using feedback to adjust its output?
Closed-loop control
Open-loop control
PID control
Fuzzy logic control
What is the main feature of a closed-loop control system?
It uses feedback to adjust output and reduce error.
It operates continuously without monitoring conditions.
It works with manual correction from the operator.
It has no sensors or feedback mechanisms.
Which control mode is most effective for unpredictable and complex processes?
Open-loop control
On-off control
Fuzzy logic control
Proportional control
Which term describes a control method that adjusts outputs based on predicted future conditions?
Model predictive control
On-off control
Adaptive control
Integral control
In adaptive control, the system primarily:
Uses only proportional gain to control variables.
Requires constant manual recalibration.
Ignores disturbances and holds constant output.
Modifies its parameters automatically based on process changes.
A PID controller maintains pressure by adjusting the control action based on:
The error, its integral, and its derivative.
The valve opening and fluid density.
The input voltage and circuit resistance.
The pressure gauge calibration constant.
What does the proportional term in a PID controller respond to?
The rate of change of the error over time.
The constant gain of the system.
The accumulated total of all previous errors.
The current error between setpoint and measured value.
The integral term in a PID controller is responsible for:
Predicting future process behavior.
Eliminating steady-state error.
Responding instantly to disturbances.
Adjusting system damping.
The derivative term helps improve:
Integral windup performance.
Constant proportional gain.
System stability and response time.
Steady-state error correction.
Pressure control loops using PID are common because they:
Operate only on manual adjustment.
Work independently from feedback signals that comes from sensors.
Function with on-off logic only.
Compensate for changes in system load or supply.
Level PID control regulates:
The pressure at the tank outlet.
The mass flow through the pipeline.
The speed of the pump motor.
The height of liquid in a tank or vessel.
In level control, the hydrostatic pressure is directly related to:
The pump efficiency and temperature.
The pipe diameter and wall thickness.
The viscosity and flow velocity.
The liquid height and fluid density.
Open-tank level control differs from closed-tank control because:
It is affected by atmospheric pressure.
It uses pneumatic actuation only.
It requires no measurement device.
It ignores hydrostatic head effects.
Which element senses the liquid level in most automated systems?
Flow control valve
Solenoid actuator
Temperature sensor
Pressure transmitter
The main goal of level PID control is to:
Operate the pump continuously at full speed when tanks need refilling.
Maintain a desired setpoint regardless of inflow changes.
Increase the flow velocity.
Reduce tank pressure variations.
Flow control using PID maintains:
The rotational speed of the drive motor only.
A constant rate of fluid through a process line.
The total energy consumption of the system.
The static pressure of the downstream tank.
A flow PID controller adjusts the control valve to:
Maintain constant head pressure.
Keep the pump suction constant.
Match the flow rate with the setpoint.
Increase discharge temperature as necessary.
Flow measurement for PID control commonly uses:
Infrared detectors.
Ultrasonic range sensors.
Optical level readers.
Differential pressure transmitters.
The derivative component in flow control helps to:
Eliminate integral offset and derive them to follow set point.
Increase steady-state error.
Predict rapid flow changes and minimize overshoot.
Reduce proportional gain.
A key challenge in flow PID control is:
Calibrating temperature sensors.
Controlling without using a transmitter.
Managing time delays due to fluid inertia.
Ignoring flow measurement noise from pipes hammer-effects.
