72 Planning the electrical installation
to the drive enclosure and motor frame. Use separate conduits for input power,
motor, and control wiring. When conduit is employed, type MC continuous
corrugated aluminum armor cable or shielded cable is not required. A dedicated
ground cable is always required.
Note: Do not run the motor wiring for more than one drive in the same conduit.
Armored cable / shielded power cable
Six-conductor (three phases and three 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 the following suppliers:
•
Belden
•
LAPPKABEL (ÖLFLEX)
•
Pirelli.
Selecting the control cables
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Shielding
All control cables must be shielded.
Use a double-shielded twisted pair cable (figure a below) for analog signals. Employ
one individually shielded pair for each signal. Do not use common return for
different analog signals.
A double-shielded cable is the best alternative for low-voltage digital signals but
single-shielded (b) twisted pair cable is also acceptable.
■
Signals in separate cables
Run analog and digital signals in separate, shielded cables. Do not mix 24 V AC/DC
and 115/230 V AC signals in the same cable.
a
b