Mechatronics Engineering Lecture 4 PDF

Mechatronics Engineering (OFRME200) LEC. 4 Level 2- Fall Semester By: Walaa Shoeib Faculty of Electronic Engineering, Menoufia University.  Check Attendance ! 2  CHAPTER 2 Sensors & Transducers Electronic Measurements- By/ Wa...

Mechatronics Engineering (OFRME200) LEC. 4 Level 2- Fall Semester By: Walaa Shoeib Faculty of Electronic Engineering, Menoufia University.  Check Attendance ! 2  CHAPTER 2 Sensors & Transducers Electronic Measurements- By/ Walaa Shoeib 3 Passive Transducers Resistance 1- Potentiometer 2- strain gauge 3- Thermistor 4- thermocouple Electronic Measurements- By/ Walaa Shoeib 4 Resistance temperature detector (RTD- PT100) Fine wire wrapped around a ceramic or glass core. Wire is made of platinum, nickel, copper. Varying in temperature causses variation in resistance 1- positive temperature coefficient( PTC) 2- negative temperature coefficient( NTC) Platinum is the best very linear and repeatable sensor Electronic Measurements- By/ Walaa Shoeib 5 Electronic Measurements- By/ Walaa Shoeib 6 Electronic Measurements- By/ Walaa Shoeib 7 Electronic Measurements- By/ Walaa Shoeib 8 Advantages of RTD 1- accurate 2- indicators are directly operated 3- can be installed and replaced 4- measurement of differential temperature is possible 5- work over wide range -200: +650° C 6- used for remote indication 7- small size 8- stable Disadvantages of RTD 1- cost 2- possibility self heating 3- large size compared to thermocouple Electronic Measurements- By/ Walaa Shoeib 9 Thermistor (NTC) Composed of mixture of metallic oxide, manganese, nickel, cobalt, copper and iron Sense From -100:+200 C R changed from 100 Ohm : 100 K Ohm Electronic Measurements- By/ Walaa Shoeib 10 Thermocouple German physicist Thomas Johann Seebeck discovered when two wires made from dissimilar metals are joined at two ends to form a loop, and if the two junctions are maintained at different temperatures, a voltage develops in the circuit. Electronic Measurements- By/ Walaa Shoeib 11 Electronic Measurements- By/ Walaa Shoeib 12 Types of thermocouple Nickel-alloy thermocouples Electronic Measurements- By/ Walaa Shoeib 13 Types of thermocouple Platinum/rhodium-alloy thermocouple Electronic Measurements- By/ Walaa Shoeib 14 Will be continued Electronic Measurements- By/ Walaa Shoeib 15