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Tài liệu cung cấp hình anh về Cảm Biến Điện Dung Và Nam Châm -mô tả chi tiế về Cảm Biến Điện Dung Và Nam Châm -mô tả cách hoạt động của Cảm Biến Điện Dung Và Nam Châm
Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 1 IntroductiontocapacitiveandmagneticSensors Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 2 Capacitive SensorSensor electrodeShieldingPrinting boardHousingPotentiometer Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 3 Physical BasicssSensor electrodeShieldTargetC = f(ε0, εr, A, s-1) Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 4 Types of Influences 1Conductive, earthed target Conductive, insulated targetIn both applications an inductive sensor should be used! Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 5 Types of influences 2Non conductive target☞This is the typical application for capacitive sensors☞The switching distance depends on the relative permitivity εr (reduction factor)εrεr Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 6 Reduction FactorReduction factorOilIcePVCCeramicsGlassAlcoholWater Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 7 Oscillator CircuitOscillatorAmplifier Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 8 Applications☞Detection of pallets made of wood, printing boards and other non conductive materials☞Level controlalso thru non conductive wallsair εr = 1εr > 1εr > 1 Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 9 Principle Magnetic SensorFerrite coreHousingCoilCableApplication: Detection of magnets thru NFE-metals Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs Kolleg GmbH, Page 10 Detection AreaIf the magnet is turned of90° this happens 2 switchingpointsDetection area has twominor lobes==> 3 switching points, if themagnet is too close to the sensor [...]... Direction of the field without magnet Direction of the field with magnet Application: Detection of magnets thru FE-metals ©Pepperl+Fuchs Kolleg GmbH, Page 11 PEPPERL+FUCHS Capacitive/Magnetic Sensors Application Sensor for the detection of position of pistons in hydraulic cylinders (thru FE-metalls) ©Pepperl+Fuchs Kolleg GmbH, Page 12 PEPPERL+FUCHS Capacitive/Magnetic Sensors Integration the magnets . GmbH, Page 3 Physical BasicssSensor electrodeShieldTargetC = f(ε0, εr, A, s-1) Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs. SensorFerrite coreHousingCoilCableApplication: Detection of magnets thru NFE-metals Capacitive/Magnetic Capacitive/Magnetic SensorsSensorsPEPPERL+FUCHS©Pepperl+Fuchs