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Appendix
EMC of wiring
Connection of screening
All leads from the VMS and to the VMS are to be screened
(exception: 230 V lead).
The screening must be laid to PE by the shortest possible route.
Correct:
screening terminal
connection termima
Wrong!
connection terminal
screening terminal
PE bus bar
On the back of the unit two bars are fitted left and right parallel to the terminal
strips. All screening is to be laid up to those bars. Although this bar already
has a connection to PE via the housing, the fault leakage conduction is
improved if a separate, low-impedance PE wire is laid to each of these in
addition.
Switch cabinet wiring
The low-voltage lines from the FMS and to the FMS should not lie parallel to
the feed and down conductors of the power electronics in a conduit.
Frequency converter lines and switches/contactors that switch high inductive
or capacitive loads are especially critical. Parallel laying with the drive lines of
solenoid valves, ignition transformers or large servomotors and the like is
therefore to be avoided.
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Although this unit to some extent far exceeds all applicable EMC standards,
suitable wiring is essential in ensuring that the entire system functions
trouble-free in all circumstances.
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Screening of leads
Screened leads from the field (e.g. potentiometer leads) are best laid directly
from the field
to the FMS (without intermediate terminals).
Should intermediate terminals be necessary, the screening is also to be led
immediately alongside via the terminal.
Long distances in the conduit without screening should be avoided.
