Lenze · E84AYCEO communication module (EtherNet/IP™) · Communication Manual · DMS 3.0 EN · 10/2013 · TD17
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4
Technical data
4.5
Internal switch latency
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4.5
Internal switch latency
The integrated 2-port switch causes runtime delays. For "store-and-forward" and 100 Mbps, these
runtime delays can be calculated as follows.
Runtime delay for an output data packet of the scanners incl. 32-bit "run/idle header" with 16-bit
sequence counter:
Runtime delay for an output data packet of an adapter without 32/bit "run/idle header":
Example
Delay of an output data packet of the scanners with 8 output data words (16 bytes):
• ((66 permanent bytes + 16 bytes) x 8 x 10 nsec) + 4
μ
sec
• (82 bytes x 8 x 10 nsec) + 4
μ
sec
• 6.56
μ
sec + 4
μ
sec =
10.56
μ
sec
Runtime delay = ((66 permanent bytes + I/O data in bytes) x 8 x 10 nsec) + 4
μ
sec
Runtime delay = ((62 permanent bytes + I/O data in bytes) x 8 x 10 nsec) + 4
μ
sec
Note!
The use of external switches can also lead to runtime delays. Depending on the system
constellation, it may be useful to create a star topology or a line/mix topology.
