Danfoss VLT AAF006, Руководство по эксплуатации

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4 Electrical Installation
4.1 Safety Instructions
See chapter 2 Safety for general safety instructions.
CAUTION
SHOCK HAZARD
The active filter can cause a DC current in the PE
conductor.
•
When a residual current-operated protective
device (RCD) is used for protection against
electrical shock, only an RCD of Type B is
permitted on the supply side.
Failure to follow the recommendation means the RCD
may not provide the intended protection.
4.2 Electrical Installation
4.2.1 Power Connections
Cabling and fusing
NOTICE
All cabling must comply with national and local
regulations on cable cross-sections and ambient
temperature. UL applications require 75
°
C copper
conductors. 75
°
and 90
°
C copper conductors are
thermally acceptable for use in non-UL applications.
The power cable connections are situated as shown in
Illustration 4.1 . The mains connection is fitted to the mains
switch if this is included. Dimension the cable cross-section
in accordance with the filter current rating, including skin
and proximity effects, derating, and local legislation.
Connect mains to terminals 91, 92 and 93. Connect ground
to the terminal on the immediate right of terminal 93.
Terminal number Function
91, 92, 93
94 Mains R/L1, S/L2, T/L3
Ground
Table 4.1 Mains and Ground Connections
The conductor predominantly carries currents of high
frequencies so the distribution of current is not evenly
dispersed throughout the cross-section of the conductor.
This is due to 2 independent effects known as skin effect
and proximity effect. Both require derating and,
consequently, the mains cable of the active filter is rated at
a higher current than the filter rating itself.
3 Phase
power
input
130BA026.10
91 (L1)
92 (L2)
93 (L3)
95 PE
Illustration 4.1 Mains Connection Diagram
NOTICE
It is insufficient to rate the power cable for the filter
current rating alone due to skin and proximity effects.
The required derating is calculated as 2 separate factors:
•
The skin factor depends on frequency of current,
cable material, and cable dimensions.
•
The proximity factor depends on the number of
conductors, diameters and distance between the
individual cables.
The proximity effect is depending on the number of
conductors, diameters and distance between the individual
cables.
The optimised mains cable is:
•
Copper wires.
•
Single conductors.
•
Bus bars.
Electrical Installation Operating Instructions
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