Siemens SIMATIC S7-300 FM 350-1 - Page 167

Encoder signals and their evaluation
8.4 Signal evaluation
FM 350-1 Counter module
Manual, 05/2011, A5E03648639-01
167
Double evaluation
Double evaluation refers to the evaluation of the positive and negative edges of signal A.
The logic level at signal B determines the count direction, i.e. the up or down count pulse.
The diagram shows the double evaluation of signals:
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Figure 8-5 Double evaluation
Quadruple evaluation
Quadruple evaluation refers to the evaluation of the positive and negative edges of signals A
and B. The logic level at the signals A and B determines the count direction, i.e. the up or
down count pulse.
The diagram shows quadruple evaluation of signals:
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Figure 8-6 Quadruple evaluation
Default
Single evaluation is set by default.