Siemens SIMATIC NET SCALANCE X-200, Руководство по эксплуатации

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Frame delay times
The number of IE Switches X-200 connected in a line influences the frame delay.
Note
Frame delay time with X‑200 without IRT
When a frame passes through X-200 IE switches, it is delayed by the Store&Forward function of
the X-200 IE switches.
• With a 64 byte frame length by approx. 10 microseconds (at 100 Mbps).
• With a 1500 byte frame length by approx. 130 microseconds (at 100 Mbps).
This means that the more X-200 IE switches the frame passes through, the longer the frame
delay.
Note
Frame delay time with X‑200 with IRT
The more X-200IRT IE switches a frame runs through, the higher the frame delay. By using the
"cut through" switching mechanism, the X-200IRT IE switches are ideal to meet the real-time
requirements of PROFINET.
Cut through is, however, not possible:
• Between a port set to 10 Mbps and a port set to 100 Mbps.
• When two packets are to be sent at the same time on one port.
In this case, an X-200 IE switch changes to Store&Forward and the delay increases.
Hardware version
You will find the hardware version of your device on the type plate. On the type plate, the
hardware version is printed as a placeholder “X”.
Example: X 2 3 4 5 6
In this case, "X" would be the placeholder for hardware version 1.
Technical specifications
SCALANCE X-200
Operating Instructions, 11/2021, C79000-G8976-C284-15
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