ABB ACS550-02 User Manual page 13

The motor cable and its PE pigtail (twisted screen) should be kept as short as
possible in order to reduce electromagnetic emission as well as capacitive current.
Motor Cable Shield
To effectively suppress radiated and conducted radio-frequency emissions, the
shield conductivity must be at least 1/10 of the phase conductor conductivity. The
requirements are easily met with a copper or aluminium shield. The minimum
requirement of the motor cable shield of the drive is shown below. It consists of a
concentric layer of copper wires with an open helix of copper tape. The better and
tighter the shield, the lower the emission level and the bearing currents.
Insulation jacket
Additional US Requirements
Type MC continuous corrugated aluminum armor cable with symmetrical grounds or
shielded power cable must be used for the motor cables if metallic conduit is not
used. For the North American market, 600 VAC cable is accepted for up to 500 VAC.
For drives rated over 100 amperes, the power cables must be rated for 70
°
F).
Conduit
Where conduits must be coupled together, bridge the joint with a ground conductor
bonded to the conduit on each side of the joint. Bond the conduits also to the drive
enclosure. Use separate conduits for input power, motor, brake resistors, and control
wiring. Do not run motor wiring from more than one drive in the same conduit.
Armored cable / shielded power cable
The motor cables can be run in the same cable tray as other 460 V power wiring.
Control and signal cables must not be run in the same tray as power cables. Six
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, LAPPKABEL (ÖLFLEX) and
Pirelli.
Copper wire screen
Helix of copper tape
11
Inner insulation
Cable core
°
C (158
Installation