The Baumer conductivity transmitters are designed for media separation and analysis in applications in the food and beverage industry and water treatment. They provide outstanding benefits in terms of accuracy and display options.
The measuring cell is a smooth, hermetically sealed body made of PEEK with a bore for the medium to flow through. The bore is surrounded by two coils: a primary coil with AC voltage and a secondary coil which receives a small , medium-induced voltage signal. The signal strength depends on the medium conductivity. The signal is electronically amplified to a linear, analog 4 ... 20 mA output signal. The Pt100 sensor installed in the tip detects the media temperature to enable temperature compensation of the typically temperature-dependent measured conductivity. The Pt100 signal is also provided as analog 4...20-mA output signal. Both coils and sensor are accommodated in the PEEK sensor housing with a surface roughness of (Ra) < 0.8 μm. This way, the conductivity sensor is perfect in hygienic processes or for aggressive media contact, such as acid or lye.
The conductivity of a liquid generally depends on the temperature. For many aqueous solutions, it increases at +2%/K. To be able to compare measurements, measuring devices refer the directly determined conductivity back to a reference temperature. This is usually defined as 25 °C. In addition to this definition, the AFI also allows the input of a temperature coefficient in %/K. This must be set to 0%/K if temperature compensation is to be dispensed with. Non-linear temperature coefficients can be specified with an additional quadratic element.