Eaton PowerXL DA1 - Mains Chokes

2 Engineering
2.4 Mains chokes
DA1 Variable Frequency Drives 11/16 MN04020005Z-EN www.eaton.com 47
2.4 Mains chokes
Mains chokes reduce the total harmonic distortion, the mains feedback and
improve the power factor. The apparent current on the mains side is then
reduced by around 30 %.
Towards the variable frequency drive, the main chokes dampen the
interference from the supply network. This increases the electric strength of
the variable frequency drive and lengthens the lifespan (diodes of the mains
power rectifier, internal DC link capacitors).
T
￫
It is not necessary to use mains chokes in order to run the DA1
variable frequency drive. However, we recommend using a mains
choke if the electrical supply system’s quality is not known.
While planning the project, consider
that a main choke is only
assigned to a single variable frequency drive for decoupling.
When using an adapting transformer (assigned to a single variable
frequency drive), a main choke is not necessary.
Main chokes are designed based on the mains-side input current
(I
LN
) of the variable frequency drive.
￫
FS5, FS6, and FS7 DA1 variable frequency drives feature mains
chokes in their DC link. Using chokes in order to reduce current
harmonics is not necessary in this case.
￫
Only for FS8 DA1 variable frequency drives:
DA1-34370FB-B20C, DA-34450FB-B20C
If it is not guaranteed that the system percentage impedance is
greater than or equal to 1%, a mains choke must be connected.
Your u
K
value should fall between 1 and 4%.
Examples:
DA1-34370FB-B20C 
DX-LN3-370
DA1-34450FB-B20C  DX-LN3-450
￫
When the frequency inverter is operating at its rated current
limit, the mains choke with a u
K
value of around 4 % causes a
reduction of the frequency inverter’s maximum possible output
voltage (U
2
) to about 96 % of the mains voltage (U
LN
).
￫
For the rated mains contactors for DA1 variable frequency
drives, please refer to the technical data chapter in
 Section 6.7, „Mains chokes“, page 172.
For more information and technical data on DX-LN…
mains chokes, please refer to instruction leaflet
IL00906003Z.
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