Festo CPX-FB11 - Field Bus Baud Rate and Field Bus Length

1. Installation
1−17
Festo P.BE−CPX−FB11−EN en 0503b
1.3.2 Field bus baud rate and field bus length
The maximum permitted field bus length depends on the
baud rate used. Tab.1/9 shows the nominal values. Detailed
specifications can be found in the manuals for the your con
trol system or scanner.
The maximum permitted length of the branch line depends on
the total length of the branch lines and the baud
rate.
Please note
· Refer to the manuals for your control system or bus in
terface for information on the T−adapter and the maxi
mum branch line length which is permitted for your
controller.
· Take into account also the sum of the branch line lengths
when calculating the maximum permitted length of the
field bus cable.
Baud rate
Maximum main
b l th
Branch line length
bus length
Maximum Cumulative
125 kBaud 500 m
6m
156 m
250 kBaud 250 m
6 m
78 m
500 kBaud 100 m 39 m
Tab.1/9: Maximum field bus and branch line lengths
depending on the baud rate (as per ODVA
specification V2.0)
Information on setting the baud rate can be found in
chapter1.2.2.