Rockwell Automation 160 SER A FRN 1.XX-4.XX - Manual (Page 17)

Chapter 2 - Installation/Wiring
2–3
Motor Cable Recommendations
A variety of cable types are acceptable for
variable speed controller installations. For many
installations, unshielded cable is adequate,
provided it can be separated from sensitive
circuits. As an approximate guide, allow a
spacing of 1 meter (3.3 feet) for every 10 meters
(33 feet) of unshielded length. If you cannot
separate motor cables from sensitive circuits, or if
you must run motor cables from multiple
controllers (more than three) in a common
conduit or cable trays, shielded motor cable is
recommended to reduce system noise.
Motor cables should be four–conductor with the
ground lead and shield (if using shielded cable)
connected to the controller ground terminal and
the motor frame ground terminal.
Long Motor Cable Effects
Installations with long motor cables may require
the addition of output reactors to reduce voltage
reflections at the motor, and reduce cable
charging current. Capacitive charging of long
motor cables may draw current in excess of the
controller rating. The output reactor should be
installed between the controller output terminals
and the motor, and mounted near the controller.
The controller should be installed as close to the
motor as possible.
Note: If your application requires motor cable
lengths exceeding the recommendations listed
below, contact your local Allen–Bradley Sales
Office.
Table 2.A Recommended Shielded Motor Cable Lengths
Recommended Max. Cable Length m (ft.)
Controller Type
kW (HP)
Voltage Economy Motor
(1000V)
Standard Motor
(1200V)
Inverter Rated Motor
(1600V)
0.37 (0.5) 230 61 (200) 61 (200) 61 (200)
0.56 (0.75) 230 107 (350) 107 (350) 107 (350)
0.75 (1.0) 230 122 (400) 122 (400) 122 (400)
1.5 (2.0) 230 152 (500) 152 (500) 152 (500)
2.2(3.0) 230 152 (500) 152 (500) 152 (500)
0.37 (0.5) 460 12 (40) А 20 (60) А 30 (100)
0.56 (0.75) 460 12 (40) А 20 (60) А 30 (100)
0.75 (1.0) 460 12 (40) А 20 (60) А 38 (125)
1.5 (2.0) 460 12 (40) А 20 (60) А 46 (150)
2.2(3.0) 460 12 (40) А 20 (60) А 90(275)
А These recommended cable lengths are based on reflected wave limitations, while all other recommended cable lengths listed above are based
on capacitive charging of long, shielded motor cables.