What is the difference between the incremental encoder and absolute encoder?！

What is the difference between the incremental encoder and absolute encoder? How to select a encoder for servo system?

Commonly used for the incremental encoder, if the position of the zero position, there are strict requirements for absolute encoder. Servo system to specific analysis, see applications.

Speed measured by conventional incremental encoder, unlimited accumulation measurement; measuring position with absolute encoder, the position of the uniqueness of (single or multi-turn), to see the final application, look at the purpose and requirements to be achieved.

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