23
UMG 103
Shielding
A twisted-conductor and shielded cable
must be provided for connections via the
RS485 interface. The shielding at both
ends of the cable must be connected
to a large area of the housing or cabinet
parts in order to achieve an adequate
shielding effect.
Cable type
Recommended cable types:
Unitronic Li2YCY(TP) 2x2x0.22 (Lapp
cables)
Unitronic BUS L2/FIP 1x2x0.64 (Lapp
cables)
Cable length
1200 m for a baud rate of 38.4 k
Correct
Incorrect
Terminal strip in the control cabinet.
Device with RS485 interface.
(Without terminating resistor)
Device with RS485 interface.
(With terminating resistor at the
device)
Terminating resistors
The cable at the start and end of a
segment is terminated by with resistors
(120 ohm, 1/4 W).
The UMG103 does not contain any
terminating resistors.
For the wiring of the Modbus
connection, CAT cables are not
suitable. Please use the recom-
mended cables.
m
