Industrial Control Systems and Sensors
40 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What does an accelerometer measure?

  • Pressure
  • Position
  • Flow
  • Acceleration (correct)

    • Which of the following devices is an example of a thermoelectric sensor?

  • Microphone
  • Laser diode
  • Photodiode
  • Thermocouple (correct)

    • What is the primary function of a sensor?

  • To convert electrical energy into motion
  • To display mechanical energy at a remote gauge
  • To transform a physical quantity into a signal (correct)
  • To receive mechanical energy and move

    • What is the term for the amount that a sensor's output varies when the measured quantity varies?

    <p>Sensitivity</p> Signup and view all the answers

    Which type of sensor is a mercury-in-glass thermometer?

    <p>Thermomechanical</p> Signup and view all the answers

    What is the primary difference between a sensor and a transducer?

    <p>A sensor transforms a signal into an electrical signal, while a transducer transforms one type of energy into another</p> Signup and view all the answers

    What is the primary function of sensors in a closed loop industrial control system?

    <p>To measure changes in the controlled physical quantity</p> Signup and view all the answers

    What is the purpose of calibrating a sensor?

    <p>To ensure the sensor's accuracy against recognized standards</p> Signup and view all the answers

    What type of energy conversion is possible with a transducer?

    <p>Electrical, electro-mechanical, electromagnetic, photonic, photovoltaic, or any other form of energy</p> Signup and view all the answers

    What is the advantage of using smaller sensors?

    <p>They have a negligible impact on the object being measured</p> Signup and view all the answers

    What is the primary application of a Cathode Ray Tube (CRT)?

    <p>To convert electrical signals into visual form</p> Signup and view all the answers

    What is the function of a Hall effect sensor?

    <p>To convert a magnetic field level into electrical form</p> Signup and view all the answers

    What is the primary function of a transducer?

    <p>To convert one type of energy to another</p> Signup and view all the answers

    What is the primary application of a photo-detector or Photo-resistor (LDR)?

    <p>To convert changes in light levels into resistance changes</p> Signup and view all the answers

    What is the primary application of a magnetic cartridge?

    <p>To convert motion into electrical form</p> Signup and view all the answers

    What is the primary function of a fluorescent lamp?

    <p>To convert electrical power into visible light</p> Signup and view all the answers

    What is the primary function of transducers in the context of sensors?

    <p>To convert physical quantities into electrical signals</p> Signup and view all the answers

    What is the main difference between contact and non-contact sensors?

    <p>Contact sensors require physical contact, while non-contact sensors do not</p> Signup and view all the answers

    What type of sensors use infrared or visible light sources and photodetectors to detect the presence or absence of an object?

    <p>Optical proximity sensors</p> Signup and view all the answers

    What is the typical application of tachogenerators?

    <p>Speed measurement and control in industrial machinery</p> Signup and view all the answers

    What type of switches detect physical contact or position changes?

    <p>Contact type switches</p> Signup and view all the answers

    What type of transducers convert sound waves into electrical signals?

    <p>Sound transducers</p> Signup and view all the answers

    What is the primary function of Hall effect sensors?

    <p>To detect magnetic fields</p> Signup and view all the answers

    What is the main advantage of non-contact sensors over contact sensors?

    <p>Minimizing wear and damage</p> Signup and view all the answers

    What is the primary advantage of micro-sensors employing MEMS technology compared to macroscopic methods?

    <p>Far higher speed and sensitivity</p> Signup and view all the answers

    What is the primary function of sensor 5 in a data acquisition system?

    <p>To monitor the internal workings of the data acquisition system</p> Signup and view all the answers

    What is the primary difference between passive and active sensors?

    <p>Passive sensors produce electric signals without using energy from the electrical circuitry</p> Signup and view all the answers

    What is the primary function of a multiplexer (MUX) in a data acquisition system?

    <p>To link each sensor individually to a direct analog-to-digital converter or a computer</p> Signup and view all the answers

    What is the primary application of sensors and transducers in modern technology?

    <p>To enable the monitoring and control of physical parameters in industrial processes</p> Signup and view all the answers

    What is the primary function of sensing elements in sensors?

    <p>To detect physical phenomena and convert them into measurable electrical signals</p> Signup and view all the answers

    What is the primary difference between a thermistor and a thermocouple?

    <p>A thermistor is a passive sensor, while a thermocouple is an active sensor</p> Signup and view all the answers

    What is the primary function of a transducer in a data acquisition system?

    <p>To convert one form of energy into another</p> Signup and view all the answers

    What is the primary function of contact type switches?

    <p>Physically making or breaking contact between conducting elements</p> Signup and view all the answers

    Which type of transducer converts sound waves into electrical signals or vice versa?

    <p>Sound transducer</p> Signup and view all the answers

    What is the primary application of Hall effect sensors?

    <p>Proximity sensing, speed measurement, and current sensing</p> Signup and view all the answers

    What is the main difference between A.C. and D.C. tachogenerators?

    <p>The output signal frequency</p> Signup and view all the answers

    Which type of switch uses the presence or absence of a magnetic field to open or close electrical contacts?

    <p>Magnet type switch</p> Signup and view all the answers

    What is the primary function of transducers in electronic systems?

    <p>To convert one form of energy into another</p> Signup and view all the answers

    What is the application of vibration transducers?

    <p>Vibration analysis, condition monitoring, and structural health monitoring</p> Signup and view all the answers

    What is the primary function of tachogenerators?

    <p>To convert rotational speed into electrical signals</p> Signup and view all the answers

    Study Notes

    Introduction to Industrial Control Systems

    • A closed-loop industrial control system consists of three steps: applying the input (reference value), controlling the process, and feedback (negative feedback) that measures the output and applies it back to the input stage.
    • Sensors are special devices that sense changes in the controlled physical quantity.
    • Transducers are devices that convert one type of energy into another.

    Types of Transducers

    • Electromagnetic transducers:
      • Convert electromagnetic waves into electric current and vice versa (e.g., antenna, cathode ray tube (CRT))
      • Convert electrical signals into visual form (e.g., CRT)
      • Convert electrical power into visible light (e.g., fluorescent lamp, light bulb)
    • Electrochemical transducers:
      • pH probes
      • Electro-galvanic fuel cell
      • Hydrogen sensor
    • Electromechanical transducers:
      • Electro-active polymers
      • Galvanometer
      • Micro-electromechanical systems (MEMS)
      • Rotary motor, linear motor
      • Vibration powered generator
    • Electrostatic transducers:
      • Electrometer
    • Photoelectric transducers:
      • Laser diode, light-emitting diode (convert electrical power into forms of light)
      • Photoresistor, phototransistor, photomultiplier tube (convert changing light levels into electrical form)
    • Thermoelectric transducers:
      • RTD (Resistance Temperature Detector)
      • Photodiode
      • Thermocouple
      • Peltier cooler
      • Thermistor (includes PTC resistor and NTC resistor)
    • Electroacoustic transducers:
      • Loudspeaker, earphone (convert electrical signals into sound)
      • Microphone (convert sound into an electrical signal)

    Sensors

    • A sensor is a device that uses one type of energy to detect a parameter and report it in another (often an electrical or digital signal).
    • Sensors can be classified as:
      • Contact sensors: require physical contact with the measured object (e.g., switches, pressure sensors, temperature sensors)
      • Non-contact sensors: operate without physical contact with the measured object (e.g., optical sensors, capacitive sensors, inductive sensors)
    • Sensors have various applications, including:
      • Automation
      • Robotics
      • Object detection
      • Position sensing
      • Industrial machinery
      • Assembly lines
      • Conveyor systems
      • Automotive applications
      • Consumer electronics

    Sensor Characteristics

    • Sensitivity: measures the amount of change in the sensor's output when the measured quantity changes
    • Sensors can affect the object being measured (e.g., thermometer cooling the liquid, liquid heating the thermometer)

    Data Acquisition and Control Systems

    • A block schematic of a data acquisition and control device consists of:
      • Sensors
      • Multiplexer (MUX)
      • Analog-to-digital (A/D) converter
      • Computer
      • Actuator
      • Control signals
    • The system can include various components and peripheral devices, such as amplifiers, sample-and-hold circuits, filters, and data recorders.

    Transducers and Sensors

    • Sensors detect physical phenomena and convert them into measurable electrical signals.
    • Transducers convert physical quantities into electrical signals.
    • Transducers can be classified as:
      • Contact type: require physical contact with the measured object
      • Non-contact type: operate without physical contact with the measured object

    Optical Proximity Sensors

    • Basic principle: detect the presence or absence of an object by emitting light and detecting changes in the reflected or transmitted light
    • Construction: consist of a light emitter (LED or laser diode) and a photodetector (photodiode or phototransistor) housed in a compact package
    • Applications: widely used in automation, robotics, object detection, and position sensing applications

    Other Types of Sensors and Transducers

    • Switches:
      • Contact type switches (e.g., push buttons, limit switches)
      • Magnet type switches (e.g., reed switches)
      • Electromagnetic type switches (e.g., relays)
    • Sound transducers: convert sound waves into electrical signals or vice versa
    • Light transducers: convert light energy into electrical signals
    • Pressure transducers: measure pressure and convert it into an electrical signal
    • Vibration transducers: convert mechanical vibrations into electrical signals
    • Hall effect sensors: detect magnetic fields and convert them into electrical signals
    • A.C./D.C. tachogenerators: convert rotational speed into electrical signals

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Understand the components of a closed-loop industrial control system, including input, control, and feedback stages. Learn about sensors and transducers, and their roles in measuring physical quantities and converting energy types.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser