Multi-turn encoder

In addition to the single-turn design, there are also multi-turn encoders that determine the absolute position over multiple revolutions.

Different technical solutions are available to detect the revolutions. There are micro-gear unit stages that are magnetically or optically scanned using code disks.

The multi-turn unit is also available as an electronic counter that saves to memory.

In the case of an optical rotary encoder, the code disks are decoupled from each other via a gear unit stage with a reduction ratio of i = 16. In other words, with 3 additional code disks (common value), 16 × 16 × 16 = 4096 revolutions can be resolved absolutely.