Inductive proximity switch for use as contactlessly working electronic switching device in automation application, has control loop controlling reception signal to zero, and balancing coil electric circuit including current measurement unit

摘要

The switch (1) has a transmitting coil (2) and two anti-serially connected receiving coils (3) for producing a reception signal. A balancing coil (4) is transformingly coupled with one of the receiving coils. The balancing coil is connected with a controllable resistor (9), which is a component of a control loop. The control loop controls the reception signal to zero. An electric circuit of the balancing coil includes a current measurement unit (10). Current flowing into the balancing coil is measured and evaluated. An independent claim is also included for a method for operating an inductive proximity switch.