Yaskawa SGDS Sigma III Servo Amplifier - Manual (Page 121)

5 Wiring
5.6.1 Wiring Precautions
5-18
5.6 Others
5.6.1 Wiring Precautions
To ensure safe and stable operation, always observe the following wiring precautions.
1. For wiring for reference inputs and encoders, use the specified cables. Refer to 4 Specifications and
Dimensional Drawings of Cables and Peripheral Devices for details.
Use cables that are as short as possible.
2. For a ground wire, use as thick a cable as possible (2.0 mm
2
(0.079 in
2
) or thicker).
• At least class-3 ground (100 Ω max.) is recommended.
• Ground to one point only.
• If the servomotor is insulated from the machine, ground the servomotor directly.
3. Do not bend or apply tension to cables.
The conductor of a signal cable is very thin (0.2 to 0.3 mm (0.0079 to 0.012 in)), so handle the cables
carefully.
4. Use a noise filter to prevent noise interference.
(For details, refer to 5.6.2 Wiring for Noise Control.)
• If the equipment is to be used near private houses or may receive noise interference, install a noise filter on
the input side of the power supply line.
• Because the SERVOPACK is designed as an industrial device, it provides no mechanism to prevent noise
interference.
5. To prevent malfunction due to noise, take the following actions:
• Position the input reference device and noise filter as close to the SERVOPACK as possible.
• Always install a surge protector in the relay, solenoid and electromagnetic contactor coils.
• The distance between a power line (such as a power supply line or servomotor cable) and a signal line must
be at least 30 cm (11.81 in). Do not put the power and signal lines in the same duct or bundle them
together.
• Do not share the power supply with an electric welder or electrical discharge machine. When the
SERVOPACK is placed near a high-frequency generator, install a noise filter on the input side of the power
supply line.
6. Use a molded-case circuit braker (QF) or fuse to protect the power supply line from high voltage.
• The SERVOPACK connects directly to a commercial power supply without a transformer, so always use
an QF or fuse to protect the servo system from accidental high voltage.
7. The SERVOPACKs do not have built-in ground protection circuits. To configure a safer system, install
an earth leakage braker for protection again overloads and short-circuiting, or install an earth leakage
braker combined with a wiring circuit braker for ground protection.
IMPORTANT