1. EKT314/4 Electronic Instrumentation
Week 3
Chapter 2: Transducer

2. Classification Applications Definition Physics Computer Science
Revise…..
Classification
Applications
Definition
Physics
Computer
Science
Transducer
Finite
State
EKT314/4 - Electronic Instrumentation

3. Classification Applications Definition Physics Computer Science
Transducer
Finite
State
EKT314/4 - Electronic Instrumentation

4. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

5. Force Humidity Flow Level Motion Applications Position Pressure
Examples of sensor
Selected sensor picture
Sensor characteristics
Sensor operation circuitry
Sensor-DAQ connection
Motion
Applications
Position
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

6. NI USB-6008/6009 DAQ ANALOG DIGITAL GND – 01 AI0 – 02 AI4 – 03
AO0 – 14
AO1 – 15
GND – 16
32 – GND
31 – +5V
30 – +2.5V
29 – PFI0
28 – P1.3
27 – P1.2
26 – P1.1
25 – P1.0
24 – P0.7
23 – P0.6
22 – P0.5
21 – P0.4
20 – P0.3
19 – P0.2
18 – P0.1
17 – P0.0
-8 analog inputs-
-2 analog outputs-
-12 digital I/O-
-32-bit counter-
EKT314/4 - Electronic Instrumentation

7. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

8. Switches RTD Temperature Thermocouple Infrared Thermistor
EKT314/4 - Electronic Instrumentation

9. Temperature Sensor RTD –Resistance Temperature Detector
Common Resistance Materials for RTDs:
Platinum (most popular and accurate)
Nickel
Copper
Balco (rare)
Tungsten (rare)
EKT314/4 - Electronic Instrumentation

10. Temperature Sensor Characteristic of Sensor
Resistance Temperature Detectors or RTDs for short, are wire
wound and thin film devices
measure temperature because of the physical principle of the
positive temperature coefficient of electrical resistance of
metals.
The hotter they become, the larger or higher the value of their
electrical resistance.
EKT314/4 - Electronic Instrumentation

11. Temperature Sensor Characteristic of Sensor
RTD’s are generally more expensive to manufacture or purchase than thermocouples.
♦ Since the RTD circuit is just a resistance circuit, no special extension leadwires or connectors are required making this portion of the circuit less expensive than that of a thermocouple.
♦ Although some types of RTD elements are rated to fairly high temperatures (650°C (1202°F)), they become quite fragile at temperatures above 320°C (600°F). A RTD sensor will not hold up well at these elevated temperatures if there is any vibration
present.
♦ The tolerance or accuracy of an RTD generally decreases as temperature increases.
EKT314/4 - Electronic Instrumentation

12. Temperature Sensor Circuit of Sensor RTD
EKT314/4 - Electronic Instrumentation

13. Temperature Sensor Connection to NI DAQ TO ANALOG INPUT OF DAQ
EKT314/4 - Electronic Instrumentation

14. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

15. PIEZOELECTRIC SENSORS
Shock Sensor
Vibration
Triaxial Sensors
Accelerometer
Handprobes
EKT314/4 - Electronic Instrumentation

16. Vibration Sensor Piezoelectric Sensors
EKT314/4 - Electronic Instrumentation

17. Vibration Sensor Characteristic of Sensor
The rugged, solid-state construction of industrial piezoelectric sensors enables them to operate under most harsh environmental conditions. They are unaffected by dirt, oil, and most chemical atmospheres. They perform well over a wide temperature range and resist damage due to severe shocks and vibrations. Most piezoelectric sensors used in vibration monitoring today contain internal amplifiers. The piezoelectric element in the sensor produces a signal proportional to acceleration. This small acceleration signal can be amplified for acceleration measurements or converted (electronically integrated) within the sensor into a velocity or displacement signal. The piezoelectric velocity sensor is more rugged than a coil and magnet sensor, has a wider frequency range, and can perform accurate phase measurements.
EKT314/4 - Electronic Instrumentation

18. Vibration Sensor Circuit of Sensor
EKT314/4 - Electronic Instrumentation

19. Vibration Sensor Connection to NI DAQ DAQ ANALOG INPUT
EKT314/4 - Electronic Instrumentation

20. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

21. MEMS mass-flow sensors
Mass Air Flow Sensor
Flow
Turbine Flow sensor
Ultrasonic Flow meter
Gas Flow Sensor
EKT314/4 - Electronic Instrumentation

22. Flow Sensor Mass Air Flow(MAF)
The Mass Air Flow(MAF) Sensor converts the amount of air drawn into the engine into a voltage signal.
EKT314/4 - Electronic Instrumentation

23. Flow Sensor Characteristic of Sensor
EKT314/4 - Electronic Instrumentation

24. Flow Sensor
Circuit of Sensor
EKT314/4 - Electronic Instrumentation

25. Flow Sensor Connection to NI DAQ DAQ ANALOG INPUT
EKT314/4 - Electronic Instrumentation

26. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

27. Load Cell Force Sensor Piezoforce sensor Force Elastic element
Magento elastic
Hydrolic Load cell
EKT314/4 - Electronic Instrumentation

28. Force Sensor Hydrolic Load Cell Sensor
EKT314/4 - Electronic Instrumentation

29. Force Sensor Characteristic of Sensor
The hydraulic load cellis a device filled with a liquid (usually oil) which has a pre-load pressure. Application of the force to the loading member increases the fluid pressure which is measured by a pressure transducer or displayed on a pressure gauge dial via a Bourdon tube
EKT314/4 - Electronic Instrumentation

30. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

31. Resistive Humidity Sensor Capacitive Humidity sensor
In capacitive humidity sensors, the effect of humidity on the dielectric constant of a polymer or metal oxide material is measured
In resistive humidity sensors, the change in electrical resistance of a material due to humidity is measured.[1] Typical materials are salts and conductive polymers. Resistive sensors are less sensitive than capacitive sensors - the change in material properties is less, so they require more complex circuitry. The material properties also tend to depend both on humidity and temperature, which means in practice that the sensor must be combined with a temperature sensor. The accuracy and robustness against condensation vary depending on the chosen resistive material. Robust, condensation-resistant sensors exist with an accuracy of up to ±3% RH.
In thermal conductivity humidity sensors, the change in thermal conductivity of air due to humidity is measured. These sensors measure absolute humidity rather than relative humidity.[1]
Thermal conductivity humidity sensor
EKT314/4 - Electronic Instrumentation

32. Humidity Sensor Resistive humidity Sensor
EKT314/4 - Electronic Instrumentation

33. Humidity Sensor Characteristic of Sensor
the change in electrical resistance of a material due to humidity is measured.[1] Typical materials are salts and conductive polymers. Resistive sensors are less sensitive than capacitive sensors - the change in material properties is less, so they require more complex circuitry. The material properties also tend to depend both on humidity and temperature, which means in practice that the sensor must be combined with a temperature sensor. The accuracy and robustness against condensation vary depending on the chosen resistive material. Robust, condensation-resistant sensors exist with an accuracy of up to ±3% RH.
EKT314/4 - Electronic Instrumentation

34. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

35. Ultrasonic Level Sensor
Optical
Ultrasonic Level Sensor
Level
Microwave
Resistive Chain
Ultrasonic level sensors are used for non-contact level sensing of highly viscous liquids, as well as bulk solids.
Optical sensors are used for point level sensing of sediments, liquids with suspended solids, and liquid-liquid interfaces. These sensors sense the decrease or change in transmission of infrared light emitted from an infrared diode (LED). With the proper choice of construction materials and mounting location, these sensors can be used with aqueous, organic, and corrosive liquids.
Microwave sensors are ideal for use in moist, vaporous, and dusty environments as well as in applications in which temperatures vary
Resistive chain level sensors are similar to magnetic float level sensors in that a permanent magnet sealed inside a float moves up and down a stem in which closely spaced switches and resistors are sealed. When the switches are closed, the resistance is summed and converted to current or voltage signals that are proportional to the level of the liquid.
Magneto resisitive
EKT314/4 - Electronic Instrumentation

36. Level Sensor Optical level Sensor
EKT314/4 - Electronic Instrumentation

37. Level Sensor Characteristic of Sensor
Optical sensors are used for point level sensing of sediments, liquids with suspended solids, and liquid-liquid interfaces.
These sensors sense the decrease or change in transmission of infrared light emitted from an infrared diode (LED).
With the proper choice of construction materials and mounting location, these sensors can be used with aqueous, organic, and corrosive liquids.
EKT314/4 - Electronic Instrumentation

38. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

39. Laser Infrared Motion CCD Acoustic (sound) Vibration
Motion can be detected by: sound (acoustic sensors), opacity (optical and infrared sensors and video image processors), geomagnetism (magnetic sensors, magnetometers), reflection of transmitted energy (infrared laser radar, ultrasonic sensors, and microwave radar sensors), electromagnetic induction (inductive-loop detectors), and vibration (triboelectric, seismic, and inertia-switch sensors). Acoustic sensors are based on: electret effect, inductive coupling, capacitive coupling, triboelectric effect, piezoelectric effect, and fiber optic transmission. Radar intrusion sensors have the lowest rate of false alarms.
Vibration
EKT314/4 - Electronic Instrumentation

40. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

41. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

42. Solid State Pressure Sensor Piezoresistive Pressure Sensor
Bourdon tube
Bellows
Pressure
Solid State Pressure Sensor x
Piezoresistive Pressure Sensor
EKT314/4 - Electronic Instrumentation

43. Pressure Sensor Piezoresistive Sensor
EKT314/4 - Electronic Instrumentation

44. Pressure Sensor Characteristic of Sensor
In piezoresistive sensors, pressure changes the resistance by mechanically deforming the sensor, enabling the resistors in a bridge circuit, for example, to detect pressure as a proportional differential voltage across the bridge.
Conventional resistive pressure measurement devices include film resistors, strain gauges, metal alloys, and polycrystalline semiconductors
EKT314/4 - Electronic Instrumentation

45. Pressure Sensor Circuit of Sensor
EKT314/4 - Electronic Instrumentation

46. Pressure Sensor Connection to NI DAQ DAQ ANALOG INPUT
EKT314/4 - Electronic Instrumentation

47. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

48. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

49. Force Humidity Flow Level Vibration Motion Applications Position Speed
Temperature
Position
Speed
Pressure
Proximity
EKT314/4 - Electronic Instrumentation

50. EKT314/4 Electronic Instrumentation
Week 3
End