ABB ACS880-87LC-4000A/4021A-7, Руководство по оборудованию

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Planning the electrical installation 59
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Single core vs multicore cables in grid cabling
Use symmetrical grid cabling. Asymmetry leads to unequal current distribution between
the conductors which may cause disturbances and fault trips. To avoid asymmetry, use
symmetrical multicore (three-phase) cables where possible. Single core cabling is also
allowed if the cables are grouped symmetrically.
The table below shows three possible cabling options.
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Additional US and Canada requirements
Use copper, copper-clad aluminum or aluminum conductors. Use conductors rated for
75 °C (167 °F) only.
Run the cabling in metallic conduits, or use type MC continuous corrugated aluminum
armor cable with symmetrical grounds or shielded power cable for the generator cables if
metallic conduit is not used.
Conduit
Bridge the joints of the conduits with a ground conductor bonded to the conduit on each
side of the joint. Bond the conduits also to the converter enclosure. Use separate conduits
for grid, generator, DC resistors, and control wiring. A dedicated ground cable is always
required.
Note: Do not run generator wiring from more than one converter in the same conduit.
Armored cable / shielded power cable
6-conductor (3 phases and 3 ground) type MC continuous corrugated aluminum armor
cable with symmetrical grounds is available from the following suppliers (trade names in
parentheses):
•
Anixter Wire & Cable (Philsheath)
•
BICC General Corp (Philsheath)
•
Rockbestos Co. (Gardex)
•
Oaknite (CLX).
Shielded power cables are available from Belden, Lapp Kabel (ÖLFLEX) and Pirelli,
among others.
No. Layout Description
1 Multicore cabling (recommended). See subsection
Alternative power cable types for the possible
constructions of the PE (protective earth/ground).
2 Single core cables in trefoil (preferable single core cabling
option).
3 Single core cables laid flat.
L2 L3
L1
L3 L1
L2
L1 L2
L3
PE L1
L3 L2
PE L1
L3 L2