For Nonius technology, the magnetic code carrier consists of two magnetic encoder tracks. The outer track consists of an even number of alternately magnetized poles and is used for high-precision position determination. It is therefore referred to as the master track. The second inner track has one fewer pair of poles than the outer track and is therefore referred to as the Nonius track. This track is used to calculate an absolute position within one revolution of the pole disk. This is done by calculating the angular difference between the two tracks. Encoders with this technology must be calibrated before use. An alternative option to Nonius technology that does not require calibration is AksIM technology.
RLS has developed a few software for use with RLS encoders.