To reduce the interference level from the entire system (unit+installation), make motor and brake cables as short as
possible. Avoid placing cables with a sensitive signal level alongside motor and brake cables. Radio interference higher than
50 MHz (airborne) is especially generated by the control electronics.
3.2.1 Emission Requirements
The EMC product standard for frequency converters
defines 4 categories (C1, C2, C3 and C4) with specified
requirements for emission and immunity.
states
the definition of the 4 categories and the equivalent classi-
fication from EN 55011.
Category Definition
Equivalent
emission
class in EN
55011
C1
Frequency converters installed in
the first environment (home and
office) with a supply voltage less
than 1000 V.
Class B
C2
Frequency converters installed in
the first environment (home and
office) with a supply voltage less
than 1000 V, which are neither
plug-in nor movable and are
intended to be installed and
commissioned by a professional.
Class A Group 1
C3
Frequency converters installed in
the second environment
(industrial) with a supply voltage
lower than 1000 V.
Class A Group 2
C4
Frequency converters installed in
the second environment with a
supply voltage equal to or above
1000 V or rated current equal to or
above 400 A or intended for use in
complex systems.
No limit line.
An EMC plan
should be
made.
Table 3.1 Correlation between IEC 61800-3 and EN 55011
When the generic (conducted) emission standards are
used, the frequency converters are required to comply
with the limits in
Environment
Generic emission
standard
Equivalent
emission class
in EN 55011
First
environment
(home and
office)
EN/IEC 61000-6-3 Emission
standard for residential,
commercial and light
industrial environments.
Class B
Second
environment
(industrial
environment)
EN/IEC 61000-6-4 Emission
standard for industrial
environments.
Class A Group 1
Table 3.2 Correlation between Generic Emission Standards and
EN 55011
Product Overview
VLT
®
Micro Drive FC 51 Design Guide
22
MG02K302 - Rev. 2013-12-03
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