500 likes | 644 Views
EKT314/4 Electronic Instrumentation. Week 3 Chapter 2: Transducer. Revise…. Classification. Applications. Physics. Computer Science. Finite State. Definition. Transducer. Classification. Physics. Computer Science. Finite State. Applications. Definition. Transducer. Vibration.
E N D
EKT314/4Electronic Instrumentation Week 3 Chapter 2: Transducer
Revise….. Classification Applications Physics Computer Science Finite State Definition Transducer EKT314/4 - Electronic Instrumentation
Classification Physics Computer Science Finite State Applications Definition Transducer EKT314/4 - Electronic Instrumentation
Vibration Flow Force Humidity Position Pressure Motion Level Applications Temperature Speed Proximity EKT314/4 - Electronic Instrumentation
Flow Force Humidity Position Pressure Motion Level Examples of sensor Selected sensor picture Sensor characteristics Sensor operation circuitry Sensor-DAQ connection Applications Proximity EKT314/4 - Electronic Instrumentation
NI USB-6008/6009 DAQ ANALOG DIGITAL GND – 01 AI0 – 02 AI4 – 03 GND – 04 AI1 – 05 AI5 – 06 GND – 07 AI2 – 08 AI6 – 09 GND – 10 AI3 – 11 AI7 – 12 GND – 13 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
Vibration Flow Force Humidity Position Pressure Motion Level Applications Speed Proximity Temperature EKT314/4 - Electronic Instrumentation
Switches Thermocouple Infrared RTD Thermistor Temperature EKT314/4 - Electronic Instrumentation
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
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
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
Temperature Sensor • Circuit of Sensor RTD EKT314/4 - Electronic Instrumentation
Temperature Sensor • Connection to NI DAQ TO ANALOG INPUT OF DAQ EKT314/4 - Electronic Instrumentation
Flow Force Humidity Position Pressure Motion Level Vibration Applications Temperature Speed Proximity EKT314/4 - Electronic Instrumentation
PIEZOELECTRIC SENSORS Triaxial Sensors Shock Sensor Handprobes Accelerometer Vibration EKT314/4 - Electronic Instrumentation
Vibration Sensor • Piezoelectric Sensors EKT314/4 - Electronic Instrumentation
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
Vibration Sensor • Circuit of Sensor EKT314/4 - Electronic Instrumentation
Vibration Sensor • Connection to NI DAQ DAQ ANALOG INPUT EKT314/4 - Electronic Instrumentation
Flow Vibration Force Humidity Position Pressure Motion Level Applications Temperature Speed Proximity EKT314/4 - Electronic Instrumentation
MEMS mass-flow sensors Ultrasonic Flow meter Turbine Flow sensor Mass Air Flow Sensor Gas Flow Sensor Flow EKT314/4 - Electronic Instrumentation
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
Flow Sensor • Characteristic of Sensor EKT314/4 - Electronic Instrumentation
Flow Sensor • Circuit of Sensor EKT314/4 - Electronic Instrumentation
Flow Sensor • Connection to NI DAQ DAQ ANALOG INPUT EKT314/4 - Electronic Instrumentation
Force Vibration Flow Humidity Position Pressure Motion Level Applications Temperature Speed Proximity EKT314/4 - Electronic Instrumentation
Piezoforce sensor Load Cell Force Sensor Hydrolic Load cell Elastic element Magento elastic Force EKT314/4 - Electronic Instrumentation
Force Sensor • Hydrolic Load Cell Sensor EKT314/4 - Electronic Instrumentation
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
Humidity Vibration Flow Force Position Pressure Motion Level Applications Temperature Speed Proximity EKT314/4 - Electronic Instrumentation
Resistive Humidity Sensor Capacitive Humidity sensor Thermal conductivity humidity sensor Humidity EKT314/4 - Electronic Instrumentation
Humidity Sensor • Resistive humidity Sensor EKT314/4 - Electronic Instrumentation
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
Level Vibration Flow Force Humidity Position Pressure Motion Applications Temperature Speed Proximity EKT314/4 - Electronic Instrumentation
Optical Ultrasonic Level Sensor Microwave Resistive Chain Magneto resisitive Level EKT314/4 - Electronic Instrumentation
Level Sensor • Optical level Sensor EKT314/4 - Electronic Instrumentation
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
Vibration Flow Force Humidity Position Pressure Level Applications Motion Temperature Speed Proximity EKT314/4 - Electronic Instrumentation
Laser Infrared CCD Acoustic (sound) Vibration Motion EKT314/4 - Electronic Instrumentation
Vibration Flow Force Humidity Pressure Motion Level Applications Temperature Speed Proximity Position EKT314/4 - Electronic Instrumentation
Vibration Flow Force Humidity Position Motion Level Applications Temperature Speed Proximity Pressure EKT314/4 - Electronic Instrumentation
Bourdon tube Piezoresistive Pressure Sensor Solid State Pressure Sensor x Bellows Pressure EKT314/4 - Electronic Instrumentation
Pressure Sensor • Piezoresistive Sensor EKT314/4 - Electronic Instrumentation
Pressure Sensor • Characteristic of Sensor In piezoresistivesensors, 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
Pressure Sensor • Circuit of Sensor EKT314/4 - Electronic Instrumentation
Pressure Sensor • Connection to NI DAQ DAQ ANALOG INPUT EKT314/4 - Electronic Instrumentation
Vibration Flow Force Humidity Position Pressure Motion Level Applications Temperature Speed Proximity EKT314/4 - Electronic Instrumentation
Vibration Flow Force Humidity Position Pressure Motion Level Applications Temperature Proximity Speed EKT314/4 - Electronic Instrumentation
Vibration Flow Force Humidity Position Pressure Motion Level Applications Speed Proximity Temperature EKT314/4 - Electronic Instrumentation
EKT314/4Electronic Instrumentation Week 3 End