different types of multi-turn encoder！

Battery-powered multi-turn encoder

This type of encoder uses a battery for retaining the counts across power cycles. It uses energy conserving electrical design to detect movements.

Geared multi-turn encoder

These encoders uses a train of gears to mechanically store the number of revolutions. The position of the single gears is detected with one of the above-mentioned technologies.

Self-powered multi-turn encoder

Theses encoders use the principle of energy harvesting to generate energy from the moving shaft. This principle, introduced in 2007, uses a Wiegand Sensor to produce electricity sufficient to power the encoder and write the turns count to non-volatile memory.

Absolute multi-turn encoder[edit]

A multi-turn encoder can detect and store more than one revolution. The term absolute multi-turn encoder is generally used if the encoder will detect movements of its shaft even if the encoder is not provided with external power.

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