Siemens SIMATIC ET 200S Operating Instructions Manual page 253

Parameters
Encoder sampling rate No limitation, 0.1 kHz to 6.3 kHz (in 0.1-
See the technical specifications of the absolute encoder.
1
The monoflop time is the time between 2 SSI frames. The assigned monoflop time must be greater than the monoflop
2
time of the absolute encoder (refer to the technical specifications of the manufacturer).
The following limitation applies to the monoflop time of the absolute encoder:
3
(1/transmission rate) < monoflop time of absolute encoder < 64 µs
Technological Functions
Operating Instructions, 06/2010, A5E00124867-07
Value Range
kHz steps)
4.8 Setting parameters for the 1SSI
Note
Any encoder sampling rate to be taken into account is
set here. This parameter is only active in isochronous
mode. It enables the use of slower encoders (such as
ultrasound encoders) even in a fast processing cycle.
An integer reduction n is calculated using the set
frequency. In this case, the encoder is read in again
only every nth clock cycle.
Example: Processing cycle 500 µs
Encoder sampling rate: 1.2 kHz (approximately every
833 µs)
--> reduction n = 2, i.e., the encoder is read in again
only every 2nd processing cycle, i.e., every ms.
1SSI
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