IRIS Net RCM-26, Руководство пользователя

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21
RCM-26 Remote Control Module
Owner’s Manual
* With longer cables and many participants on the CAN-bus, termination
resistors with higher impedance than the specified 120
Ω
are recommended to
reduce the ohmic load of the interface drivers and therefore the voltage drop
between the two cable-ends.
The following table is meant for first assessment of necessary cable diameters
for different bus lengths and bus-participant numbers.
Additionally, the length of branch lines - for participants that are not directly
connected to the CAN-bus - is also of importance. For data transfer rates of up
to 125 kbit/s, the maximum length of a single stub cable should not exceed 2
meters. For higher bit rates a maximum length of only 0.3 meter is still
permissible. The entire length of all branch lines should not exceed 30 meters.
Bus Length
(in m)
Data Transmission Cable
Termination
(in
Ω
)
Max. Data
Transfer Rate
Resistance
per Unit
Length
(in m
Ω
/m)
Cable Diameter
0...40 < 70
0,25...0,34 mm²
AWG23, AWG22
124
1000 kbit/s
at 40 m
40...300 < 60
0,34...0,6 mm²
AWG22, AWG20
127
500 kbit/s
at 100 m
300...600 < 40
0,5...0,6 mm²
AWG 20
150...300*
100 kbit/s
at 500 m
600...1000 < 26
0,75...0,8 mm²
AWG 18
150...300*
62,5 kbit/s
at 1000 m
Bus Length
(in m)
Number of Units on the CAN-Bus
32 64 100
100 0,25 mm²/AWG24 0,34 mm²/AWG22 0,34 mm²/AWG22
250 0,34 mm²/AWG22 0,5 mm²/AWG20 0,5 mm²/AWG20
500 0,75 mm²/AWG18 0,75 mm²/AWG18 1,0 mm²/AWG17