Absolute singleturn and multiturn encoders have established themselves as the standard method for measuring linear displacement or angular position.
With absolute encoders a reference trip is no longer needed after system start-up or a power-down.
Multiturn encoders in particular are now being employed, where previously incremental encoders had predominated, for example with geared motors or in lifts.
Today all manner of multiturn encoders are available in a variety of designs. As a rule the manufacturers offer either mechanical gears for ‘counting turns’, or swear by electronic counters with electronic data storage. They are critical of any other technology.
The fact is however: it is not a case of which is better or worse; each technology has its advantages and drawbacks. Only the actual application can decide.
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