SENSOR TRANSDUCER Busran Pre Apakah Sensor Itu Apakah

SENSOR / TRANSDUCER Busran

Pre • Apakah Sensor Itu? ? • Apakah Transduser itu? ? ? • Berikan gambaran Implementasi Sensor/Transduser

Definisi • Sensor adalah piranti yang mentransform (mengubah) suatu nilai (isyarat/energi) fisik ke nilai fisik yang lain (Electric) • Menghubungkan antara fisik nyata dan industri electric dan piranti elektronika • Di dunia industri berguna untuk monitoring, controlling, dan proteksi • Sering disebut juga dengan Transducer

Transducer • Sensor adalah piranti yang mentransform (mengubah) suatu nilai (isyarat/energi) fisik ke nilai fisik yang lain. • Piranti yang memberikan output (yang bisa dipakai) sebagai tanggapan terhadap (measurand) kondisi, kuantitas fisik masukan. • Ada beberapa kategori measurand

Sensor • Tidak terbatas pada pengukuran besaran fisik saja, tetapi juga pada kimia, dan biologi

Detectable Phenomenon Stimulus Acoustic Biological & Chemical Electric Magnetic Quantity Wave (amplitude, phase, polarization), Spectrum, Wave Velocity Fluid Concentrations (Gas or Liquid) Charge, Voltage, Current, Electric Field (amplitude, phase, polarization), Conductivity, Permittivity Magnetic Field (amplitude, phase, polarization), Flux, Permeability Optical Refractive Index, Reflectivity, Absorption Thermal Temperature, Flux, Specific Heat, Thermal Conductivity Mechanical Position, Velocity, Acceleration, Force, Strain, Stress, Pressure, Torque

Sensor • Ada 6 tipe isyarat • Mechanical, contoh: panjang, luas, mass flow, gaya, torque, tekanan, kecepatan, percepatan, panjang gel acoustic, dll • Thermal, contoh: temperature, panas, entropy, heat flow • Electrical, contoh: tegangan, arus, muatan, resistance, frekuensi, dll • Magnetic, contoh: intensitas medan, flux density, dll • Radiant, contoh: intensitas, panjang gelombang, polarisasi, dll • Chemical, contoh: komposisi, konsentrasi, p. H, kecepatan reaksi, dll

Physical Principles • Amperes’s Law – A current carrying conductor in a magnetic field experiences a force (e. g. galvanometer) • Curie-Weiss Law – There is a transition temperature at which ferromagnetic materials exhibit paramagnetic behavior • Faraday’s Law of Induction – A coil resist a change in magnetic field by generating an opposing voltage/current (e. g. transformer) • Photoconductive Effect – When light strikes certain semiconductor materials, the resistance of the material decreases (e. g. photoresistor)

Choosing a Sensor

Sensor • Sensor mengkonversi dari suatu isyarat input ke suatu isyarat ouput. • Sensor bisa saja menggunakan satu atau lebih pengkonversian untuk menghasilkan suatu isyarat keluaran

Diskusi • Apa perbedaan antara Sensor dan Transduser? • Isyarat apa saja yang mampu dirubah oleh Sensor atau Transduser?

Sensor Block Diagram Primary Transduction measurand Isyarat input • Blok diagram sensor Secondary Transduction Isyarat output

Passive Sensor • Mengkonversi sifat-sifat/isyarat fisik atau kimia ke dalam isyarat yang lain tanpa bantuan sumber energi • Contoh : termocouple • Termocouple menghasilkan tegangan output sebanding dengan suhu pada sambungan termcouple tersebut

Active Sensor • Mengkonversi sifat-sifat/isyarat fisik atau kimia ke dalam isyarat yang lain dengan bantuan sumber energi • Merupakan pilihan utama untuk isyarat yang lemah/kecil

Active Sensor Primary Transduction measurand Secondary Transduction Isyarat output Isyarat input Auxiliary Energy Source • Blok Diagram Active Sensor

Analog Output • Active sensor di industri elektronika mempunyai standar isyarat listrik baik analog (berupa tegangan atau arus) maupun digital

Digital Output • Computer Based atau Microprocessor

Temperature Sensor • Temperature sensors appear in building, chemical process plants, engines, appliances, computers, and many other devices that require temperature monitoring • Many physical phenomena depend on temperature, so we can often measure temperature indirectly by measuring pressure, volume, electrical resistance, and strain

Temperature Sensor • Bimetallic Strip • Application – Thermostat (makes or breaks electrical connection with deflection)

Temperature Sensor • Resistance temperature device.

Accelerometer • Accelerometers are used to measure along one axis and is insensitive to orthogonal directions • Applications – Vibrations, blasts, impacts, shock waves – Air bags, washing machines, heart monitors, car alarms • Mathematical Description is beyond the scope of this presentation. See me during lunch if interested

Light Sensor • Light sensors are used in cameras, infrared detectors, and ambient lighting applications • Sensor is composed of photoconductor such as a photoresistor, photodiode, or phototransistor

Magnetic Field Sensor • Magnetic Field sensors are used for power steering, security, and current measurements on transmission lines • Hall voltage is proportional to magnetic field

Ultrasonic Sensor • Ultrasonic sensors are used for position measurements • Sound waves emitted are in the range of 2 -13 MHz • Sound Navigation And Ranging (SONAR) • Radio Dection And Ranging (RADAR) – ELECTROMAGNETIC WAVES !!

Photogate • Photogates are used in counting applications (e. g. finding period of period motion) • Infrared transmitter and receiver at opposite ends of the sensor • Time at which light is broken is recorded

CO 2 Gas Sensor • CO 2 sensor measures gaseous CO 2 levels in an environment • Measures CO 2 levels in the range of 0 -5000 ppm • Monitors how much infrared radiation is absorbed by CO 2 molecules

Kesimpulan dan Diskusi

Tugas Kelompok • Implementasi Sensor dalam Dunia Industri – Sensor Cahaya, Sensor Berat, Sensor Suhu, Sensor Suara, Sensor Jarak, Sensor Regangan • Makalah : – Teori Pengantar Sensor – Rangkaian Elektronika Sensor – Prinsip Kerja – Algoritma Program dalam Implementasi (Opsional)

Tugas Kelompok • Browsing, Reading, Resuming and Writing • Presentating of Paper

HART • • • Highway Addressable Remote Transducer Salah satu protocol komunikasi untuk sensor Untuk remote data acquisition dan kontrol Standart 4 to 20 m. A, Teknik FSK Digital format : 1200 & 2200 (logic 1 & 0)