Motors; Precautions On Wiring - YASKAWA UAK series User Manual

7 Wiring

7.1.1 Precautions on Wiring

7.1

Motors

• Separate the motor main circuit cable wiring from the I/O signal cable and encoder cable at least 30 cm,
and do not bundle or run them in the same duct.
Placing these cables too close to each other may result in malfunction.
• The maximum wiring length is 3 m for I/O signal cables, 20 m for encoder cables or motor main circuit
cables, and 10 m for control power supply cables (+24 V, 0 V).
• Do not connect the motor directly to a commercial power supply.
The motor may be damaged. Connect the motor to the correct SERVOPACK.
7.1.1

Precautions on Wiring

(1) Cables
Standard Cables
Standard motor main circuit cables, encoder cables, and relay cables cannot be used in cases where high flexi-
bility is needed, as when the cables themselves move or are twisted or turned. Use flexible cables for flexible
applications.
Flexible Cables
Even if the recommended bending radius R is followed in the mechanical design, incorrect wiring may cause
the early disconnection. Observe the following precautions when wiring.
• Cable twisting
Straighten the flexible cables wiring.
Twisted cables cause the early disconnection. Check the indication on the cable surface to make sure that the
cable is not twisted.
• Fixing method
Do not fix the moving points of the flexible cable, or stress on the fixed points may cause early disconnec-
tion.
Fix the cable at the minimum number of points. Do not put stress on the motor-end and SERVOPACK-end
connectors.
• Cable length
If the cable length is too long, it may result the cable sagging. If the cable length is too short, excessive ten-
sion on the fixed points will cause the early disconnection. Use a flexible cable with the optimum length.
• Interference between cables
Avoid interference between cables.
Interference limits the motion of flexible cable, which causes early disconnection. Keep enough distance
between cables, or provide a partition when wiring.
(2) Cable Stress
Make sure there is no bending or tension on the cables themselves, the connections, or the cable lead inlets.
Be especially careful to wire encoder cables and brake cables for main circuit so that they are not subject to
stress because the core wires of encoder cables and brake cables for main circuit are very thin at only 0.2 to 0.3
2
mm .
7-2
CAUTION