2.9.3 EMC Test Results (Emission)
The following test results were obtained using a system with an adjustable frequency drive (with options, if relevant), a shielded control cable, a
control box with potentiometer, as well as a motor and motor-shielded cable.
RFI filter type
Phase
type
Conducted emission.
Maximum shielded cable length.
Radiated emission
Industrial environment
Housing,
trades and light
industries
Industrial envi-
ronment
Housing, trades and
light industries
Set-up:
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
1.5–30 hp [1.1–22 kW] 220–240 V
S2
150
150
50
Yes
No
0.34–60 hp [0.25–45 kW] 200–240 V
T2
150
150
50
Yes
No
10–50 hp [7.5–37 kW] 380–480 V
S4
150
150
50
Yes
No
0.5–125 hp [0.37–90 kW] 380–480 V
T4
150
150
50
Yes
No
H2
1.5–30 hp [1.1–22 kW] 220–240 V
S2
25
No
No
No
No
0.34–5 hp [0.25–3.7 kW] 200–240 V
T2
5
No
No
No
No
7.5–60 hp [5.5–45 kW] 200–240 V
T2
25
No
No
No
No
0.5–10 hp [0.37–7.5 kW] 380–480 V
T4
5
No
No
No
No
10–50 hp [7.5–37 kW] 380–480 V
S4
25
No
No
No
No
15–125 hp [11–90 kW] 380–480 V
T4
25
No
No
No
No
150–1350 hp [110–1000 kW] 380–480 V
T4
50
No
No
No
No
1–125 hp [0.75–90 kW] 525–600 V
T6
150
No
No
No
No
15–125 hp [11–90 kW] 525–690 V
T7
Yes
No
No
No
No
60–1600 hp [45–1200 kW] 525–690 V
T7
150
No
No
No
No
H3
0.34–60 hp [0.25–45 kW] 200–240 V
T2
75
50
10
Yes
No
0.5–125 hp [0.37–90 kW] 380–480 V
T4
75
50
10
Yes
No
H4
150–1350 hp [110–1000 kW] 380–480 V
T4
150
150
No
Yes
No
15–125 hp [11–90 kW] 525–690 V
T7
No
Yes
No
Yes
No
60–550 hp [45–400 kW] 525–690 V
T7
150
30
No
No
No
Hx
1–125 hp [0.75–90 kW] 525–600 V
T6
-
-
-
-
-
Table 2.1: EMC Test Results (Emission)
2.9.4 General Aspects of Harmonics Emission
An adjustable frequency drive takes up a non-sinusoidal current from the
line power, which increases the input current I
RMS
. A non-sinusoidal cur-
rent 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 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 prevent an overload of the transformer and high
temperature in the cables.
2 Introduction to the VLT AQUA Drive
VLT
®
AQUA Drive Design Guide
2-22
MG.20.N5.22 - VLT
®
is a registered Danfoss trademark
2
