Lenze EMF2133IB - Manual (Page 25)

Installation
Electrical installation
Wiring with a host (master)
5
l
25 EDSMF2133IB EN 5.0
Number of bus devices
M
1 2 3
S S S S S
R R
2133PFB004
Segment Master (M) Slave (S) Repeater (R)
1 1
2 31
30 −
−
2 − 30 1
3 − 30 1
I
Tip!
Repeaters do not have a device address. When calculating the maximum
number of bus devices, they reduce the number of devices by 1 on each side of
the segment.
Repeaters can be used to build up line and tree topologies. The maximum total
bus system expansion depends on ...
ƒ the baud rate used;
ƒ the number of repeaters used.
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