Magnetic encoders！

Magnetic encoders operate analogously, substituting
magnetic coding for optical coding.
Some applications involving long travel distances may
require a multi-turn design, in which a secondary disc
(or discs) geared to the primary code disc tracks the
number of rotations of the primary. Each time the
primary disk completes a revolution, the secondary disk
indexes. This design thus assigns a unique coordinate for
each shaft position corresponding to each revolution of
the index disc, up to 4096 revolutions encoders.

absolute encoder, incremental encoder, hybrid encoder, non-magnetic encoder, multi-turn encoder, multi-turn combination encoder, draw wire encoder, digital readout, linear scale

Previous：Low Cost RSA Plastic Shell Hand Wheel Manual Pulse Encoder
Next：Roundss absolute encoders angle measuring encoder low cost