SIGMATEST

Accurate and reliable conductivity measurement made easy. The SIGMATEST is a portable eddy current instrument which measures the electrical conductivity of non-ferromagnetic metals based on the complex impedance of the measuring probe. It determines physical and technical material properties. Typical applications include controlling the quality of manufactured products, testing material combinations, and sorting metals, alloys, and scrap metal. The unit is also used for the maintenance of aircrafts, determining heat damage, and in-process controls during production and processing in the metallurgy sector. It features five different excitation frequencies and an extremely high measuring accuracy. The unit retains this high level of accuracy even at a high frequency of 960 kHz, making it possible to measure very thin workpieces with great precision. The measuring instrument is able to automatically standardize the measured value of the electrical conductivity to 20°C due to an integrated temperature compensation. The measurement quality meets Boeings (BAC 5651) and Airbus standards.

Operating Modes
The SIGMATEST is capable of operating in either Touch- or Continuous mode. Use Continuous mode to scan surfaces and display the measurement values in a time chart or Touch to measure single values. Use the recording function to save all measurements.

Correction Factor
Variations in the material geometry can produce a measurement error. One example is measurement on test pieces with curved (either concave or convex) surfaces. If the conductivity value of the test piece is known, the error caused by the curvature of the surface can be corrected by using a correction factor. The measured value is multiplied by the correction factor and the corrected value is displayed on the LCD.

The SIGMATEST "remembers"
The SIGMATEST now automatically receives the correct calibration curve from the probe. This feature is especially useful when using both 5 mm, 8 mm and 14 mm probes with the same instrument.

Temperature compensation
The SIGMATEST compensates for temperature related electrical conductivity variations. A default temperature coefficient is installed in each instrument. In addition, the user can define a specific temperature coefficient to optimize the results for specific applications. Temperature measurement is performed using either the temperature sensor which is integrated into the probe or by connecting an external temperature sensor. An external temperature sensor is recommended when the temperature of the test piece differs from the probe temperature.