Danfoss VLT AQUA Drive Series - Page 29

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 screened control cable, a control box with potentiometer, as well as a motor and motor screened cable.
RFI filter type
Pha
se
type
Conducted emission.
Maximum shielded cable length.
Radiated emission
Industrial environment
Housing,
trades and
light indus-
tries
Industrial en-
vironment
Housing, trades
and light indus-
tries
Setup: S / T
EN 55011
Class A2
EN 55011
Class A1
EN 55011
Class B
EN 55011
Class A1
EN 55011 Class B
H1 meter meter meter
1.1-22 kW 220-240 V S2 150 150 50 Yes No
0.25-45 kW 200-240 V
T2 150 150 50 Yes No
7.5-37 kW 380-480 V
S4 150 150 50 Yes No
0.37-90 kW 380-480 V
T4 150 150 50 Yes No
H2
1.1-22 kW 220-240 V
S2 25 No No No No
0.25-3.7 kW 200-240 V T2 5NoNo No No
5.5-45 kW 200-240 V
T2 25 No No No No
0.37-7.5 kW 380-480 V
T4 5NoNo No No
7.5-37 kW 380-480 V
S4 25 No No No No
11-90 kW 380-480 V
T4 25 No No No No
110-1000 kW 380-480 V
T4 50 No No No No
0.75-90 kW 525-600 V
T6 150 No No No No
11-90 kW 525-690 V
T7 Yes No No No No
45-1200 kW 525-690 V
T7 150 No No No No
H3
0.25-45 kW 200-240 V
T2 75 50 10 Yes No
0.37-90 kW 380-480 V T4 75 50 10 Yes No
H4
110-1000 kW 380-480 V
T4 150 150 No Yes No
11-90 kW 525-690 V T7 No Yes No Yes No
45-400 kW 525-690 V
T7 150 30 No No No
Hx
0.75-90 kW 525-600 V
T6 - - - - -
Table 2.1: EMC Test Results (Emission)
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 trans-
formed 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 Hz 250 Hz 350 Hz
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 cur-
rents at a low level to avoid overload of the transformer and high
temperature in the cables.
VLT
®
AQUA Drive Design Guide 2 Introduction to VLT AQUA Drive
MG.20.N5.02 - VLT
®
is a registered Danfoss trademark 29
2