3-4
Communications Processor CP 541
EWA 4NEB 812 6188-02
Connect the bus cable to the bus connector, as explained in the instructions
with the bus connector.
The PG/PLC interface and the SINEC L2 interface are safety-separated (iso-
lated) via optocouplers.
The reference potential and protective conductor terminal are internally con-
nected.
Logic
PG/PLC
SINEC L2
24 V
M
Figure 3-1 Isolation of Terminals
As a rule, you should use a grounded arrangement. This offers very high re-
jection of interference. Any interference currents are discharged from the rail
to the protective conductor.
You configure the CP 541 with a grounded reference potential by connecting
the protective conductor terminal of the CP 541 to the protective conductor.
Use a copper conductor with a cross-section of 2.5 mm.
To use the CP 541 in an ungrounded arrangement, you must fit the rail on
which the CP 541 is mounted, in an insulated arrangement. In the installed
state, the reference potential of the CP 541 is electrically connected to the
rail.
To discharge interference, you must connect the rail via an RC network to the
protective conductor.
Values for the network:
Parallel connection of R=100 k
Ω
und C=1
µ
F.
Connect the cable shields of the SINEC L2, and of the connecting cable be-
tween CP 541 and the programmable controller, to a shield bar at each end.
Further instructions for EMC-oriented configuration can be found in the
manual for the connected programmable controller.
Connecting the
Bus Cable
Electrical Separa-
tion (Isolation)
Grounded
Configuration
Ungrounded
Configuration
Shielding
EMC Guidelines
Installing and Connecting the CP 541
