Danfoss VLT AQUA Drive Design Manual page 33

®
VLT AQUA Drive Design Guide
2.10.3. 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
Setup
H1
0.25-45 kW 200-240 V
0.25-90 kW 380-480 V
H2
0.25-3.7 kW 200-240 V
5.5-45 kW 200-240 V
0.25-7.5 kW 380-480 V
11-90 kW 380-480 V
110-450 kW 380-480 V
75-500 kW 525-600 V
H3
0.25-45 kW 200-240 V
0.37-90 kW 380-480 V
H4
110-450 kW 380-480 V
75-315 kW 525-600 V
Hx
0.25-90 kW 525-600 V
Table 2.1: EMC Test Results (Emission)
2.10.4. General Aspects of Harmonics Emission
A frequency converter takes up a non-sinusoidal current from mains,
which increases the input current I
RMS
formed by means of a Fourier analysis and split up into sine-wave
currents with different frequencies, i.e. different harmonic currents I
with 50 Hz as the basic frequency:
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.
NB!
Some of the harmonic currents might disturb communication equipment connected to the same transformer or cause resonance in
connection with power-factor correction batteries.
Conducted emission.
Maximum shielded cable length.
Industrial environment
EN 55011 EN 55011
Class A2 Class A1
meter meter
150 150
150 150
5 No
25 No
5 No
25 No
50 No
150 No
75 50
75 50
150 150
150 30
- -
. A non-sinusoidal current is trans-
N
®
MG.20.N4.02 - VLT is a registered Danfoss trademark
2. Introduction to VLT AQUA Drive
Radiated emission
Housing, Industrial
trades and environment
light indus-
tries
EN 55011 EN 55011
Class B Class A1
meter
50 Yes
50 Yes
No No
No No
No No
No No
No No
No No
10 Yes
10 Yes
No Yes
No No
- -
Harmonic currents I
1
Hz 50
Hz
2
Housing, trades
and light indus-
tries
EN 55011 Class B
No
No
No
No
No
No
No
No
No
No
No
No
-
I I
5 7
250 Hz 350
Hz
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