What is the measuring principle of magneto-inductive distance sensors?

Magneto-inductive distance sensors (Patented Pending).

The mainSENSORis based on an innovative measuring principle developed by Micro-Epsilon in order to combine the advantages of both inductive and magnetic sensors.

A magnet is fixed to the measurement object. The movement of the magnet induces a change in the magnetic flow in the sensor element, which is detected by the sensor coil. A linear relationship between output signal and magnet distance (self-linearization technology) is produced due to counteracting physical effects.

Different magnet with magnet strength are applied thus providing option of difference measuring ranges, up to 55 mm, these sensors are also used in special applications such as rotational speed measurement of, e.g., shafts and gear wheels.

Characteristics

Ideal alternative to inductive sensors and proximity sensors
Linear output signal, high basic sensitivity and temperature stability
Selectable measuring ranges up to 55mm with different magnets
Long-life sensor due to non-contact measurement
Ideal for customer-specific designs and serial applications

Advantages

Linear relation between signal and magnet distance (self-linearization) despite large, frontal measuring range

Compared to Hall Effectsensors

Linear output signal

Increased frontal measuring range

Compared to inductive sensors

Significantly larger measuring range

Stable sensitivity at end of measuring range

Compact sensor design (e.g. M12 with MR of 55 mm)

Flexible sensor concept

Due to their flexible concept, the sensors are ideal for a wide range of applications, particularly where big quantity and low priceare required. The standard sensors are designed in a stainless steel M12, M18 and M30 or a flat plastic housings suitable for industrial applications. Customer-specific modifications to the plate and sensor housing can be easily carried out for serial applications.

Defining the measuring range using magnets

With the magneto-inductive measuring principle, the magnets used act as target. To achieve difference measuring range, it is only necessary to change the magnet. Further calibration or sensor settings are superfluous. Therefore, measuring ranges of 20 to 55mm can be achieved using only one sensor.

Measurement through objects

Unlike conventional measuring methods, the magneto-inductive sensors enable measurements through non-ferromagnetic materials, particularly metals such as aluminum or stainless steel. A clear benefit is provided here as the sensor and the magnet can be installed separately in applications with closed systems or housings. It is therefore possible to mount the sensor safely in harsh environments.