Concentration monitoring – glycol-water


The refrigerant in a refrigeration circuit is in most cases a mixture of ethylene glycol and water. The optimum concentration is determined depending on the minimum temperature entering the circuit in order to prevent the liquid from freezing. At the same time, the aim is to keep the water content as high as possible, as this has a positive effect on thermal conductivity. So how can the concentration of the glycol-water mixture in the process be monitored? With TrueDyne’s DLO-M1 sensor you collect the necessary data to determine the concentration of the medium in the running process.

1. density sensor with integrated glycol-water concentration calculation. 2. concentration is directly output as measured value. 3. refrigeration system and concentration processing for cooling industrial applications. 4. heat exchanger on the roof of factory buildings. Due to the circulation water can evaporate and the concentration of the refrigerant changes. Here the DLO-M1 is used for concentration monitoring.

Sensors for this application

Density sensor DLO-M1 for liquids

The DLO-M1 sensor measures the density of liquids in a microelectromechanical system (MEMS system). Within the MEMS system, the liquid is directed to an omega-shaped microchannel, the so-called omega chip. This tiny silicon tube – it is hardly thicker than a hair – is vibrated for the measurement. The density of the medium to be measured can be derived from the natural frequency of this oscillation.


Data sheet


Viscosity sensor VLO-M1 for liquids

Viscosity data can be used to determine the properties of liquids and monitor their quality. The sensor measures the viscosity in the running process – even in the smallest of spaces. Irrespective of the viscosity, the sensor also measures the density and temperature of the medium being measured.


Data sheet


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