Serviceline Industrial Sensors
Serviceline Explosion Protection

Magnetic Immersion Probe

Measurement principle

Magnet-operated immersion probes are used in clean liquids, such as solvents or oils. The float, guided by a probe tube, floats on the liquid surface. By means of its magnetic field, the ring magnet built into the float activates the reed contacts installed in the guide pipe. These are switched when the float is located in the appropriate position.

The reed contacts are designed as normally closed, normally open or change-over contact switches. The measurement is independent of the electrical properties of the liquid, pressure, temperature and density.

Operation mode

Limit value magnet-operated immersion probes are designed for use in clean fluids, such as water, solvents, oils and fuels. Versions are available depending on the fluids:

  • Plastic for aggressive acids and lyes
  • Stainless steel for water, oils etc
  • Stainless steel in Ex version for flammable fluids such as fuels, solvents, alcohols

To give the reed contact a dual-stable switching characteristic, the magnet-operated immersion probe with 3 contacts has 2 floats and corresponding adjustment rings.