Cable Lengths And Number Of Nodes - Danfoss VLT 5000 Operating Instructions Manual

Cable lengths and number of nodes

The maximum cable length of a segment depends on
the transmission speed. The total cable length includes
stub lines, if applicable. A stub line is the connection
from the main bus cable to each node if a "T"
connection exists instead of a direct connection of the
main bus cable to the nodes; cf. the stub line length.
The following table shows the maximum permitted
cable lengths and the maximum number of nodes or
frequency converters with 1, 2, 3 or 4 bus segments.
Please note that a repeater switched between two
segments represents a node in both segments.
The number of frequency converters is based on
Maximum total bus cable length
Transmission speed 1 segment:
32 nodes (31
frequency converters)
[m]
9.6-187.5 kBaud 1000
500 kBaud 400
1.5 MBaud 200
3-12 MBaud 100
MG.90.G1.02 - VLT is a registered Danfoss trademark
VLT® 5000/ 5000 FLUX/ 6000 HVAC/
8000 AQUA PROFIBUS
a system with only one master. In the case of
multiple masters, the number of frequency converters
must be reduced accordingly.
The total stub line length of a segment is
limited as follows:
Stub line length
Transmission speed
9.6-93.75 kBaud
187.5 kBaud
500 kBaud
1.5 MBaud
3-12 MBaud
2 segments: 3 segments:
64 nodes (1 repeater, 96 nodes (2 repeater,
61 frequency 91 frequency
converters) [m] converters) [m]
2000 3000
800 1200
400 600
200 300
Max. stub line length
per segment [m]
96
75
30
10
none
4 segments:
128 nodes (3 repeater,
121 frequency
converters) [m]
4000
1600
800
400
9