BUILD-IN TOUCH TERMINAL
ETT 771
15.07.2020
Page 21
8
CAN Bus Setup
This section explains how to correctly configure the CAN bus. The following parameters
must first be set: Station number and data transfer rate.
8.1
CAN Bus Station Number
Each CAN bus station is assigned its own station number. With this station number, data
can be exchanged with other stations connected to the bus. In a CAN bus system however,
each station number can only be assigned once!
8.2
Number of CAN Bus Participants
The maximum number of participants on the CAN bus depends on the cable length, termi-
nation resistance, data transfer rate and the drivers used in the participants.
With a termination resistance of 120
, at least 100 participants are possible.
8.3
CAN Bus Data Transfer Rate
Various data transfer rates (baud rates) can be set on the CAN bus. The longer the bus line
is, the lower the data transfer rate that must be selected.
Value
Baud Rate
Maximum Length
0
615 kbit/s*
60 m
1
500 kBits/s
80 m
2
250 kBits/s
160 m
3
125 kBits/s
320 m
4
100 kBits/s
400 m
5
50 kbits/s
800 m
6
20 kbits/s
1200 m
7
1 Mbits/s
30 m
*only between devices with EDGE2 technology
These values apply to the following cable: 120
Twisted Pair.
Note: For the CAN bus protocol: 1 kbits/s = 1 kBaud
