Pepperl+Fuchs LB Series Manual page 45

LB Remote I/O System
Installation
Bus system
MODBUS
PROFIBUS DP
PROFIBUS PA
FOUNDATION fieldbus H1
Service bus
Repeaters or fiber optic cables such as FOL7250* can be used to extend the cable length.
In accordance with DIN EN 61158 and DIN EN 61784, the following principles apply:
Linear bus structure without branches, consisting of a cable with terminators

Length of the spur to the node < 0.3 m

Total length of all spurs < 6 m

Data transfer via shielded twisted pair cable

Terminator resistance 100  ... 130 

Core cross-section > 0.22 mm², approx. 60 pF/m

Max. cable length 1200 m, depending on the transfer rate

Max. 32 active or passive nodes including repeaters

Max. 3 repeaters between 2 nodes

Example!
The following trip values result at rates below 93.75 kBit/s and with the cables connected in
series:
0 repeaters

• Max. cable length: 1200 m
• 1 master + 31 remote I/O stations, each with 48 I/O modules = 1488 I/O modules
1 repeater

• Max. cable length: 2400 m
• 1 master + 61 remote I/O stations, each with 48 I/O modules = 2928 I/O modules
Transfer rate
1.2 kbit/s ... 9.6 kbit/s
19.2 kbit/s
38.4 kbit/s
115.2 kbit/s
9.6 kbit/s
19.2 kbit/s
93.75 kbit/s
187.5 kbit/s
500 kbit/s
1.5 Mbit/s
31.25 kbit/s
31.25 kbit/s
9600 bit/s
Max. cable length
1200 m
1200 m
1200 m
1000 m
1200 m
1200 m
1200 m
1000 m
400 m
200 m
1900 m
1900 m
1200 m
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