Eaton DC1-S1011NB-A20CE1 1, Инструкция по установке и настройке параметров

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2 Engineering
2.5 Mains chokes
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DC1-S…20…, DC1-S…OE1 Variable Frequency Drives 05/21 MN040058EN www.eaton.com
2.5 Mains chokes
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
￫
For the operation of the DC1-S… variable frequency drive, the
application of main chokes is not necessary.
However, we recommend using a mains choke if the electrical
supply system’s quality is not known:
• Large voltage peaks (e.g., when switching large loads
directly)
• Correction systems (without series inductors)
• Power supplied via conductor bar or slip ring systems
(e.g., overhead conveyors)
While planning the project, consider that a mains 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.
Mains chokes are designed based on the mains-side input
current (I
LN
) of the variable frequency drive.
￫
When the variable frequency drive is running at its rated current
limit, the mains choke with a u
K
value of around 4 % will cause
the variable frequency drive’s maximum possible output voltage
U
2
to be reduced to about 96 % of the mains voltage U
LN
.
￫
For the rated mains contactors for DC1-S… variable frequency
drives, please refer to
￫ section 4.4, “Mains chokes”, page 92.