
Installation
Electrical installation
Wiring with a host (master)
l
22
EDS82ZAFPC201 EN 4.0
Specification of the transmission cable
)
Note!
Only use cables complying with the listed specifications of the PROFIBUS user
organisation.
Field
Values
Specific resistance
135 ... 165
W
/km, (f = 3 ... 20 MHz)
Capacitance per unit length
£
30 nF/km
Loop resistance
< 110
W
/km
Core diameter
> 0.64 mm
Core cross−section
> 0.34 mm
2
Cores
Twisted double, insulated and shielded
Bus cable length
The length of the bus cable depends on the baud rate used:
Baud rate [kbps]
Length [m]
9.6 ... 93.75
1200
187.5
1000
500
400
1500
200
3000 ... 12000
100
)
Note!
The baud rate depending on the data volume, cycle time, and number of nodes
should only be selected as high as required for the application.
I
Tip!
For high baud rates we recommend to consider the use of optical fibres.
Advantages of optical fibres:
ƒ
On the transmission path external electromagnetic interference remains
ineffective.
ƒ
Bus lengths of several kilometres are also possible with higher baud rates.
The bus length
– is irrespective of the baud rate.
– depends on the optical fibre used.