Siemens SCALANCE X-200 Operating Instructions Manual page 95

1) Bus adapters with FC interfaces have the same temperature values as bus adapters with
RJ-45 interfaces.
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.
SCALANCE X-200
Operating Instructions, 02/2018, C79000-G8976-C284-12
Technical specifications
95