SONATEC is a highly precise sound velocity sensor for determination of sound velocities and concentrations (e. g. of acids, caustics, emulsions or solvents). The sensor can be used for instance for phase detection and for monitoring of crystallization processes.


The sound velocity sensor SONATEC continuously measures the velocity of sound through liquids. The instrument is designed for applications requiring maximum sensitivity and highest accuracy. It is easy to operate and maintenance-free. For sound velocity measurement a sound pulse is created by a piezo-element in a sonic transmitter. It moves perpendicular to the product flow towards a sonic receiver where it is detected. Since the distance between transmitter and receiver is known, the sound velocity can easily be calculated by measuring the travel time of the sonic signal. As a specific property of each liquid, the correlation between concentration and sound velocity can be described by a mathematical polynomial. With decades of experience and our own laboratory facilities, Centec know the polynomials for a large number of products. Any temperature drifts of the measured signal are automatically compensated for by an internal Pt1000 sensor. SONATEC can display sound velocity and concentration in various units. For sound velocity measurement in tanks, Centec offer a variety of specially designed SONATEC sensors.

European patent application: 1 439 438 B1

  • Most accurate technology to determine sound velocity and concentration
  • Patented compact design with local display available
  • Large variety of materials and flange connections
  • Hygienic execution and full CIP capability
  • Easy to operate and maintenance-free

Technical Data

Measuring Range 400 - 3.000 m/s
Accuracy ± 0,05 m/s
Repeatability ± 0,01 m/s
Response Time ≤ 1 s
Pressure of Operation max. 16 bar
Temperature of Operation - 25 - + 125 °C
Temperature Sensor Pt1000
Material 1.4404/1.4435/AISI 316L; Hastelloy; Tantalum; others on request
Connections DIN-, ANSI-, JIS- and other flange connections in different sizes and immersion lengths (sensor head) available
Input Transmitter Version 6 x digital (24 VDC)
Output Transmitter Version 3 x digital (24 VDC) & 2 x analog (4 - 20 mA)
Profibus DP Transmitter Versionoption
Profibus DP Sensor (w/o local display) standard
Enclosure Rating IP65
Explosion Protection (ATEX) Ex II 2G EEx d IIC T6 option
Power Supply 24 VDC


Tel.: +49 6181 18 78 0
Fax: +49 6181 18 78 50


SONATEC - Datasheet / Datenblatt
(0,77 MB, PDF, EN/DE)