Cảm biến điện dung và nam châm

Introduction to capacitive and magnetic Sensors Capacitive Sensor Sensor electrode Shielding Printing board Housing Potentiometer Physical Basics C = f(e0, er, A, s-1) Types of Influences 1 Conductive, earthed target Conductive, insulated target In both applications an inductive sensor should be used! Types of influences 2 Non conductive target This is the typical application for capacitive sensors The switching distance depends on the relative permitivity r (reduction factor) r r Reduction Factor Oscillator Circuit Oscillator Amplifier Applications Detection of pallets made of wood, printing boards and other non conductive materials Level controlalso thru non conductive walls Principle Magnetic Sensor Ferrite core Housing Coil Cable Application: Detection of magnets thru NFE-metals Detection Area Detection area has two minor lobes==> 3 switching points, if the magnet is too close to the sensor Principle Application: Detection of magnets thru FE-metals Application Sensor for the detection of position of pistons in hydraulic cylinders (thru FE-metalls) Integration the magnets