MS/m means Mega-Siemens per m, which corresponds to 1,000,000 Siemens/m. This unit is the inverse (reciprocal) of the unit of measurement for the specific electrical resistance Ohm x mm²/m. 1 Siemens therefore corresponds to 1/Ohm.
IACS stands for "International Annealed Copper Standard". This unit of measure is often used in Britain and the United States. The following applies: The specific electrical conductivity of 100 %IACS corresponds to 58 MS/m. Using this relation, it’s possible to convert any value of electrical conductivity from the one unit of measurement to the other.
The specific electrical conductivity is directly dependent on the temperature: The higher the temperature, the lower the conductivity. So that the measured values are comparable, the conductivity is always given with reference to 20 °C. That’s why the Fischer conductivity standards also give values for 20 °C.
In order for the SIGMASCOPE to convert a measured value of the actual conductivity to 20 °C, the following conditions must be met:
- Either the instrument must be calibrated at the same temperature as the measurement
- Or the temperature of the sample must be recorded with a temperature probe (internal/external) during measurement and calibration
If these conditions are not met, systematic measurement errors may occur.