1 about absolute encoders, Introduction, About absolute encoders – HEIDENHAIN PROFINET User Manual
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Introduction
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Introduction
With an absolute encoder each angular position is assigned a
coded position value generated by a code disc equipped with
several parallel fine graduations tracks which are scanned individ-
ually. On single turn encoders, i.e. an encoder producing absolute
positions within one revolution, the absolute position information
repeats itself with every revolution. So called multi turn encoders
can also distinguish between revolutions. The numbers of unique
revolutions is determined by the resolution of the multi turn scan-
ning and repeats itself after the total resolution is reached. A ma-
jor benefit of absolute encoder type is that if the encoder loses
power, the encoder is able to keep track of its position also if the
shaft is turned during the power loss. This is due to the genuine
An absolute encoder can also be used to calculate a digital speed
value. By internally dividing the difference in position with a small
delta time an accurate speed value can be calculated and trans-
mitted to the subsequent electronics for closed loop control.