SD710 Series Servo Drive User Manual Chapter 3 Wiring and Installation
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3.6 Anti-interference Countermeasures for Electrical Wiring
To suppress interference, take the following measures.
(1) The command input cable length should be 3m or less, and the encoder cable should be 20m or less.
(2) Use thick wire (2mm² or more) for grounding wiring whenever possible.
①
It is recommended to use grounding of type D or higher (grounding resistance of 100Ω or less).
②
One point must be grounded. .
(3) Use a noise filter to prevent RF interference. When using in a residential environment or an environment with high
voltage interference noise, install a noise filter on the input side of the power cord.
(4) To prevent malfunction caused by electromagnetic interference, the following treatment method can be used.
①
Install the host computer as well as the noise filter as close to the servo drive as possible.
②
Install surge suppressors on the coils of relays, solenoids, and solenoid contactors.
③
When wiring separate the strong current line from the weak current line and keep them more than 30cm
apart. Do not put them into the same conduit or bundle them together.
④
Do not share the power supply with a welding machine, electrical discharge processing equipment, etc. When
there is a high frequency generator nearby, install a noise filter on the input side of the power cord.
3.6.1 Example of Interference-Resistant Wiring and Grounding Treatment
The main circuit of the driver uses "high-speed switching elements", and depending on the peripheral wiring and
grounding treatment of the servo driver, switching noise may affect the normal operation of the system. Therefore, proper
grounding methods and wiring must be used, and noise filters must be added when necessary.
(1) Example of Interference-resistant Wiring
Servo
system
U
V
W
L1
L2
L3
CN2
M
PG
Noise
filter
(3 phase)
3.5mm²
above
3.5mm²
above
2mm²
above
Earth
grounding
Ground
plate
Figure 3.20 Example of interference-resistant wiring
