Danfoss VLT AQUA Drive FC 202 Design Manual page 138

How to Install
•
Avoid terminating the screen with twisted ends
(pigtails). It increases the high frequency
impedance of the screen, which reduces its
effectiveness at high frequencies. Use low
impedance cable clamps or EMC cable glands
instead.
•
Avoid using unscreened motor or control cables
inside cabinets housing the frequency converter,
whenever possible.
Leave the screen as close to the connectors as possible.
5 5
Illustration 5.96 shows an example of an EMC-correct
electrical installation of an IP20 frequency converter. The
Illustration 5.96 EMC-Correct Electrical Installation of a Frequency Converter in Cabinet
136
Design Guide
Panel
PLC etc.
PLC
Min. 16 mm 2
Equalizing cable
Control cables
Min. 200mm
between con-
trol cables,
motor cable and
Mains-supply
mains cable
L1
L2
L3
PE
Reinforced protective earth
Danfoss A/S © Rev. 06/2014 All rights reserved.
frequency converter is fitted in an installation cabinet with
an output contactor and connected to a PLC, which is
installed in a separate cabinet. Other ways of doing the
installation could have just as good an EMC performance,
provided the guidelines to engineering practice are
followed.
If the installation is not carried out according to the
guideline and if unscreened cables and control wires are
used, some emission requirements are not complied with,
although the immunity requirements are fulfilled. See
chapter 2.10.3 EMC Test Results (Emission).
Output con-
tactor etc.
Earthing rail
Cable insula-
tion stripped
All cable entries in
one side of panel
Motor cable
Motor, 3 phases and
Protective earth
MG20Z202