Danfoss VLT HVAC Drive FC 100 Series, Руководство по конструкции

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NOTE!
If a retrofit application requires unequal amount of wires
per phase, please consult the factory for requirements and
documentation or use the top/bottom entry side cabinet
busbar option.
5.2.4 Electrical Installation of Motor Cables
Shielding of cables
Avoid installation with twisted shield ends (pigtails). They
spoil the shielding effect at higher frequencies.
If it is necessary to break the shield to install a motor
isolator or motor contactor, the shield must be continued
at the lowest possible HF impedance.
Cable length and cross-section
The Adjustable frequency drive has been tested with a
given length of cable and a given cross-section of that
cable. If the cross-section is increased, the cable
capacitance - and thus the leakage current - may increase,
thereby requiring that the cable length is reduced
accordingly.
Switching frequency
When adjustable frequency drives are used together with
sine-wave filters to reduce the acoustic noise from a
motor, the switching frequency must be set according to
the sine-wave filter instructions in
14-01 Switching
Frequency .
Aluminum conductors
Aluminum conductors are not recommended. Terminals
can accept aluminum conductors but the conductor
surface has to be clean and the oxidation must be
removed and sealed by neutral acid free Vaseline grease
before the conductor is connected.
Furthermore, the terminal screw must be retightened after
two days due to the softness of the aluminum. It is crucial
to keep the connection a gas-tight joint, otherwise the
aluminum surface will oxidize again.
5.2.5 Enclosure Knock-outs
130BB118.10
Ø26.3
Figure 5.8 Cable entry holes for enclosure A5. The suggested use
of the holes are purely recommendations and other solutions
are possible.
Ø33,1 Ø33,1
Ø33,1
Ø26.3 Ø17
A
B C
130BA609.11
Ø21
Figure 5.9 Cable entry holes for enclosure B1. The suggested use
of the holes are purely recommendations and other solutions
are possible.
M25
M32 M25 M32 M32
130BB325.10
A C B
D D Ø18
Figure 5.10 Cable entry holes for enclosure B1. The suggested
use of the holes are purely recommendations and other
solutions are possible.
Ø42.9 Ø33.1 Ø42.9
Ø26.3 Ø17
130BA610.11
A B C
Figure 5.11 Cable entry holes for enclosure B2. The suggested
use of the holes are purely recommendations and other
solutions are possible.
How to Install
VLT
®
HVAC Drive Design Guide
5-12 MG11BB22 - VLT
®
is a registered Danfoss trademark
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