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Termination resistors
Each bus segment must be terminated by a ter-
mination resistor. The termination resistors may
be contained in the plugs of some manufactur-
ers, and can be switched on optionally.
Cable length
The allowed cable length depends on the used cable and the baud rate. The length of the cable is
determined by the distance between the bus driver of the first instrument and the bus driver of the
last instrument.
We can only recommend shielded cables, which correspond to the standard EN50170-2 wire type
A. This cable type can be provided by all leading cable manufacturers.
m
Attention!
If the feeding voltage for the resistors is
taken from the UMG96S, the Profibus can
be short-circuited in case the UMG96S
does not get a sufficient operating voltage.
The communcaition on Profibus might
break down.
In order to avoid this effect, the +5V and
GND for the termination resistors must be
feeded independently.
Diagr. Bus connection for Profibus DP
Pin 1
Pin 2
Pin 3
Pin 4
Pin 5
Pin 6
Pin 7
Pin 8
Pin 9
DSUB-9 plug
A
B
DGND
Shielding is not connected
in UMG96S
VP
UMG96S
Option Profibus
Baud rate
[kBit/s]
9,6
19,2
45,45
93,75
187,5
500
1500
Cable length
[m]
1200
1200
1200
1200
1000
400
200
The allowed cable length, using cable type A is:
120 Ohm
1/4W
390 Ohm
1/4W
390 Ohm
1/4W
+5V
GND
A (green)
B (red)
Содержание UMG 96S
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