Eaton easy800, Руководство пользователя

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6 The network Net
6.4 Network transmission security
Control Relay easy800 11/11 MN04902001Z-EN www.eaton.com
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The default settings for the input and output devices are:
6.4 Network transmission security
easyNet is a CAN-based network with the same error detection capability as
CAN. A BOSCH study relating to undiscovered and corrupt messages
determined the following:
The probability of non-discovery of a corrupted message (residual error
probability) is:
< 10
–10
message error rate.
The message error rate depends on:
• Bus loading
• Telegram length
• Malfunction frequency
• Number of stations
Example using a network with:
• 500 Kbaud
• average bus load 25 %
• average operating time 2000 h/year
• average error rate of 10
–3
, i.e.: 1 message is faulty every 1000
• transmission of 1.12
-
10
10
messages per year of which 1.12
-
10
7
messages are faulty
• Residual error probability: r < 10
–10
-
10
–3
= 10
–13
This means: one of 10
13
messages is so corrupt that the fault cannot be
recognised as such. For a network, this corresponds to a working time of
approx. 1000 years.
SEND IO å
REMOTE RUN å
REMOTE IO å