2.9.3 EMC Test Results (Emission)
The following test results have been obtained using a
system with a frequency converter (with options if
relevant), a screeened control cable, a control box with
potentiometer, as well as a motor and motor screened
cable.
RFI filter type
Conducted emission
Maximum shielded cable length
Radiated emission
Industrial environment
Housing,
trades and
light industries
Industrial
environment
Housing, trades and
light industries
Standard
EN 55011
Class A2
EN 55011
Class A1
EN 55011
Class B
EN 55011
Class A1
EN 55011
Class B
H1
1.1-45 kW 200-240 V
T2
150 m
150 m
50 m
Yes
No
1.1-90 kW 380-480 V
T4
150 m
150 m
50 m
Yes
No
H2
1.1-3.7 kW 200-240 V
T2
5 m
No
No
No
No
5.5-45 kW 200-240 V
T2
25 m
No
No
No
No
1.1-7.5 kW 380-480 V
T4
5 m
No
No
No
No
11-90 kW 380-480 V
T4
25 m
No
No
No
No
110-250 kW 380-480 V
T4
150 m
No
No
No
No
H3
1.1-45 kW 200-240 V
T2
75 m
50 m
10 m
Yes
No
1.1-90 kW 380-480 V
T4
75 m
50 m
10 m
Yes
No
H4
110-1000 kW 380-480
V
T4
150 m
150 m
No
Yes
No
Hx
1.1-90 kW 525-600 V
T6
-
-
-
-
-
Table 2.11 EMC Test Results (Emission)
HX, H1, H2 or H3 is defined in the type code pos. 16 - 17 for EMC
filters
HX - No EMC filters built in the frequency converter (600 V units only)
H1 - Integrated EMC filter. Fulfil Class A1/B
H2 - No additional EMC filter. Fulfil Class A2
H3 - Integrated EMC filter. Fulfil class A1/B (Frame size A1 only)
H4 - Integrated EMC filter. Fulfil class A1
2.9.4 General Aspects of Harmonics
Emission
A frequency converter takes up a non-sinusoidal current
from mains, which increases the input current I
RMS
. A non-
sinusoidal current is transformed by means of a Fourier
analysis and split up into sine-wave currents with different
frequencies, i.e. different harmonic currents I
n
with 50 Hz
as the basic frequency:
Harmonic currents
I
1
I
5
I
7
Hz
50
250
350
Table 2.12
The harmonics do not affect the power consumption
directly but increase the heat losses in the installation
(transformer, cables). Consequently, in plants with a high
percentage of rectifier load, maintain harmonic currents at
a low level to avoid overload of the transformer and high
temperature in the cables.
Illustration 2.21
Introduction
VLT
®
Refrigeration Drive Design Guide
28
MG16G102 - VLT
®
is a registered Danfoss trademark
2
2