Siemens SIMATIC SCALANCE X-300M PoE, Краткое руководство по эксплуатации

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Mean time between failure (MTBF)
The value in the following table applies to the basic device without media modules.
MTBF > 30 years
1)
1)
This value applies at 40 °C.
In the calculation of the MTBF of a modular switch, the standard parts count applies; in other
words, the reciprocals of all component failure rates are added.
The reciprocal of this total id the MTBF of the entire assembly.
07%)
WRWDO
07%)
EDVLFGHYLFH
07%)
PRGXOHQ
07%)
PRGXOH
Note
The IE Switches X-300 support "full wire speed switching" complying with IEEE 802.3 on all
ports. The number of packets therefore depends on the packet length.
Full wire speed switching
Number of frames per second At a frame length of
At 100 Mbps At 1000 Mbps
148810 1488095 64 bytes
84459 844595 128 bytes
45290 452899 256 bytes
23496 234962 512 bytes
11973 119732 1024 bytes
9615 96154 1280 bytes
8127 81274 1518 bytes
Note
The following applies to IE Switches X-300:
The number of IE Switches X-300 connected in a line influences the frame delay time. When
a frame passes through the switch, this is delayed by the Store&Forward function of the
IE Switch X-300 by the following values:
● at 64 bytes frame length: Delay of approx. 10 microseconds (at 100 Mbps)
● at 1500 bytes frame length: Delay of approx. 130 microseconds (at 100 Mbps)
This means, the more IE Switches X-300 a frame runs through, the higher the frame delay.
Technical data
7.4 Other properties
SCALANCE X-300M PoE
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Compact Operating Instructions, 11/2019, A5E02630810-13