YASKAWA SGD7S

4.1 Wiring and Connecting SERVOPACKs
4.1.2 Countermeasures against Noise
4-5
4
Wiring and Connecting SERVOPACKs
To ensure safe, stable application of the servo system, observe the following precautions when
wiring.
• Use the cables specified by Yaskawa. Design and arrange the system so that each cable is
as short as possible.
Refer to the following manual for information on the specified cables.
Σ-7-Series Peripheral Device Selection Manual (Manual No.: SIEP S800001 32)
• The signal cable conductors are as thin as 0.2 mm
2
or 0.3 mm
2
. Do not subject them to
excessive bending stress or tension.
4.1.2 Countermeasures against Noise
The SERVOPACK uses microprocessors. Therefore, it may be affected by switching noise from
peripheral devices.
To prevent the noise from the SERVOPACK or the peripheral devices from causing malfunc-
tions of any devices, take the following countermeasures against noise as required.
• Install the input reference device and Noise Filter as close to the SERVOPACK as possible.
• Always install a Surge Absorber for relays, solenoids, and Magnetic Contactor coils.
• Do not place the following cables in the same duct or bundle them together. Also, separate
the cables from each other by at least 30 cm.
•Main Circuit Cables and I/O Signal Cables
•Main Circuit Cables and Encoder Cables
• Do not share the power supply with an electric welder or electrical discharge machine. If the
SERVOPACK is placed near a high-frequency generator, install Noise Filters on the input side
on the Main Circuit Power Supply Cable and Control Power Supply Cable even if the same
power supply is not shared with the high-frequency generator. Refer to the following section
for information on connecting Noise Filters.
Noise Filters on page 4-6
• Implement suitable grounding measures. Refer to the following section for information on
grounding measures.
4.1.3 Grounding on page 4-8
• Use a molded-case circuit breaker (1QF) or fuse to protect the main circuit. The SERVOPACK
connects directly to a commercial power supply; it is not isolated through a transformer or
other device. Always use a molded-case circuit breaker (1QF) or fuse to protect the servo sys-
tem from accidents involving different power system voltages or other accidents.
• Install an earth leakage breaker. The SERVOPACK does not have a built-in ground fault protec-
tive circuit. To configure a safer system, install a ground fault detector against overloads and
short-circuiting, or install a ground fault detector combined with a molded-case circuit breaker.
• Do not turn the power supply ON and OFF more than necessary.
• Do not use the SERVOPACK for applications that require the power supply to turn ON and
OFF frequently. Such applications will cause elements in the SERVOPACK to deteriorate.
• After you have started actual operation, allow at least one hour between turning the power
supply ON and OFF (as a guideline).
Important
The SERVOPACK is designed as an industrial device. It therefore provides no measures to pre-
vent radio interference. The SERVOPACK uses high-speed switching elements in the main circuit.
Therefore peripheral devices may be affected by switching noise.
If the equipment is to be used near private houses or if radio interference is a problem, take
countermeasures against noise.
Important