FAQ00418 of Proximity Sensors FAQ

The circuit composition and the principle of operation are as follows.

1. Circuit composition (The same as the E2E)

High frequency oscillation type: The most general one of oscillation stop type

2. Principle of operation

The aluminum chips with small density are not detected, and the detection only of the sensing object is enabled by setting the oscillation frequency lower than usually though it is the same circuit composition as high frequency oscillation type such as the E2E Series.

There are characteristics that the eddy current caused in the sensing object concentrates on the surface of the sensing object (skin effect). The lower the frequency of the high frequency magnetic field (oscillating frequency) is, the deeper the depth that the eddy current flows (epidermal depth) is by the high frequency magnetic field from the proximity sensor.

By using this, the epidermal depth of the eddy current is deepened and the influence is reduced (the magnetic flux is penetrated) by lowering the oscillating frequency of the sensor, the aluminum chip is penetrated and the sensing object is detected.