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Conductivity sensors and transmitters for all industries

Conductivity sensors and transmitters

Products for high precision conductivity measurement in all industries

In many applications conductivity is crucial for process control, product monitoring, water monitoring, or leakage detection. We provide reliable and accurate instruments for all measurement ranges and conditions, such as ultrapure water, CIP cycles, hazardous areas or hygienic processes. Check out our broad offering of conductive and toroidal conductivity sensors, transmitters and helpful calibration tools by clicking on the button below.

How to select conductivity sensors

Conductivity sensors and transmitters are used in many industries such as food & beverage, chemicals, life sciences, pharma, water and power. The sensor selection depends on the application and the conductivity range. To measure low conductivities in pure and ultrapure water, choose conductive sensors. Use toroidal sensors in media with high conductivity (e.g. milk, beer, bases, acids, brine) and apply 4-electrode sensors where a wide measuring range is required (e.g. phase separation).

The conductivity of a liquid can be measured using the conductive or toroidal measuring principles. This video shows what it is about and how these measuring principles work.

The four-electrode conductivity measurement is suitable for broad measuring ranges or when the ion concentration in a liquid is very high. This video shows how the measuring principle works.

Conductivity measurement with conductive sensors

Conductive probes feature two electrodes that are positioned opposite from each other. An alternating voltage is applied to the electrodes which generates a current in the medium. The intensity of the current depends on the number of the medium's free anions and cations that move between the two electrodes. The more free anions and cations the liquid contains, the higher the electrical conductivity and the current flow. The conductivity unit is "Siemens per meter".

Conductive conductivity measuring principle ©Endress+Hauser

Conductivity measurement with conductive 4-electrode sensors

A high ion concentration in the medium leads to a mutual repulsion of the ions and thus a reduction of the current - the so called polarization effect. This can influence the measuring accuracy of conductive probes. 4-electrode sensors have two electrodes that are currentless and therefore not affected by the polarization effect. They measure the potential difference in the medium. A connected transmitter uses the measured potential difference and current to calculate the conductivity value.

Four-electrode conductive conductivity measuring principle ©Endress+Hauser

Conductivity measurement with toroidal / inductive sensors

Toroidal probes contain a transmission and a reception coil and measure conductivity in several steps:

  1. An oscillator generates an alternating magnetic field in the transmission coil, which induces a voltage in the medium.

  2. The medium's cations and anions start to move generating an alternating current.

  3. This induces an alternating magnetic field and thus a current to flow in the reception coil.

The current intensity and the conductivity increase with the number of free ions in the medium.

Inductive conductivity measuring principle ©Endress+Hauser


  • We offer helpful conductivity calibration solutions and conductivity calibration standards for accurate measurements.

  • The exact cell constant of the conductivity sensors is factory-measured and certified.

  • Our portfolio of conductivity sensors and transmitters covers all conductivity measuring ranges and all commonly used process connections.

  • Compact devices consisting of conductivity sensor and transmitter are perfectly suitable for the food & beverage industry.


    Conductivity measurement in industrial processes

    Selection and engineering guide for different industries and applications.