7
To ground a shielded cable, use a metal cable clamp or similar device that will maintain contact with the
entire circumference of the shielded cable. Attach a cable clamp as close to the end of the cable as
possible, and connect it to an appropriate grounding point as shown in the figure.
Shielded cable
Cable clamp
◆
Others
●
Connect the motor/speed controller and other peripheral control equipment directly to the grounding
point so as to prevent a potential difference from developing between grounds.
●
When relays or electromagnetic switches are used together with the system, use mains filters and CR
circuits to suppress surges generated by them.
●
Keep cables as short as possible without coiling and bundling extra lengths.
●
Place the power cables such as the motor and power-supply cables as far apart [100 to 200 mm
(4 to 8 in.)] as possible from the control cables. If they must cross, do so at a right angle. Place the
AC input cable and output cable of a mains filter separately from each other.
◆
Example of motor and speed controller installation and wiring
Motor
Capacitor
Speed controller
Cable clamp
Control cable
[2 m (6.6 ft.)]
Power cable
Motor cable [10 m (32.8 ft.)]
Mains filter Surge arrester
Cable clamp
Grounded panel
