Danfoss VLT CDS 803, Руководство пользователя

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PE
FC
PE
FC
e
3
0
b
b
9
2
4
.1
2
PE PE
69
69
68
68
1
2
<10 mm
Illustration 41: Twisted-pair Cables without Terminal 61
1 Minimum 16 mm
2
(6 AWG)
2 Equalizing cable
6.5.8 RFI Filter Switch
For power sizes 6.0–10 kW (8.0–15 hp), disable the RFI filter by removing the screw.
For power sizes 18.5–22 kW (20–25 hp), removing the screw does not have any electrical effect and does not alter any RFI settings.
For power size 30 kW (40 hp), no options are available for disabling the RFI filter.
e
3
0
b
b
6
1
2
.1
0
1
1 EMC screw
N O T I C E
If reinserted, use only M3x12 screw.
6.6 Harmonics Emission
A drive takes up a non-sinusoidal current from mains, which increases the input current I
RMS
. A non-sinusoidal current is trans-
formed with a Fourier analysis and split into sine-wave currents with different frequencies, that is, different harmonic currents I
n
with 50 Hz basic frequency:
Table 21: Harmonic Currents
I
1
I
5
I
7
Hz 50 250 350
The harmonics do not affect the power consumption directly, but increase the heat losses in the installation (transformer, cables).
So, 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.
e
7
5
h
a
0
3
4
.1
0
Illustration 42: DC-link Coils
AJ330233902305en-000201 / 130R0596 | 61 Danfoss A/S © 2021.05
Electrical Installation
Considerations
VLT® Compressor Drive CDS 803
Design Guide