Single-turn encoders are capable of sensing the absolute position within a revolution, while multi-turn encoders, additionally, code the number of revolutions.
For absolute encoder, the following output transmission types are available:
- SSI (Synchronous Serial Interface)
Both SSI and EnDat are ideal in time-critical applications while Profibus-DP is more suitable for plant applications with large number of encoders due to reduced wiring expense.
Encoders with Profibus-DP are programmable.
Single turn encoders resolve one rotation (360 degrees mechanical) into a specific number of steps; a unique code word is then assigned to each position; and finally values are repeated when 360 degrees are reached.
Multiturn encoders also record the number of revolutions, in addition to the absolute position within one revolution. To do this, further code discs which are coupled through gear stages with the encoder shaft are scanned.