Lenze E84DGFCA - Manual (Page 32)

Data transfer
Synchronisation
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Lenze · Decentralised frequency inverter 8400 motec (AS-Interface option) · EDS84DMOTASI EN 4.0 - 09/2013
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7.3 Synchronisation
The synchronisation serves to read in or output all input and output data exactly at the same time
and independent of the slave address. The jitter of the outputs can be reduced from ± 2.5 ms to
± 154 μs.
In a standard data exchange, the outputs of each slave that receives a data call from the master are
updated immediately and the input information are read in. For the 1st slave, this occurs approx.
154 μs before the 2nd slave and for this slave again approx. 154 μs before the 3rd etc.
If all the slaves are in a synchronised state, the information at their inputs and outputs is only
synchronised once at the beginning of the cycle. Since each slave can recognise when a new AS-i
cycle starts, no special additional synchronisation command is required. Thus, the information
exchange within the cycle remains the same. In order that the synchronisation works, not every
slave has to be in a synchronised state.