vacon • 16
Filter types
Local contacts: https://www.danfoss.com/en/contact-us/contacts-list/
Typical values as a function of cable length are as follows:
Figure 7. Typical motor voltage p.u. as a function of motor cable length (m)
Due to the inductance in series with the load there is a voltage drop across the dU/dt filter,
decreasing the voltage available for the motor. At full rated current this drop is about 5 V.
Filters are chosen so that their rated current > drive rated current. They will thermally withstand
the same overload specifications as the drive. For VACON
®
NX there is only one range of filters,
suitable for the voltage range from 380 to 690 V. The filters can also be used at lower voltages, if
required.
NOTE!
The dU/dt filters are designed for a switching frequency of 1.5 kHz for 690 V AC and 3.6 kHz
for 500 V AC voltage level. DO NOT EXCEED THIS VALUE, as there is a risk of overheating. Using
lower switching frequencies is not a problem.
NOTE!
The dU/dt filters are designed for the maximum output frequency of 70 Hz. If this value is
exceeded there is a risk of overheating. If higher output frequency is requested then the drive output
current is needed to decrease. Motor frequency de-rating for different filter types is shown in
Chapter 3.4.
7124_uk
0.5
1
1.5
2.0
2.5
0
0
100
200
300
400
500
Motor cable length [m]
M
o
to
r
v
o
lta
ge
p
.u
Содержание RFI-0012-5-IP54
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