Delta ASD-A3-0121, Руководство пользователя

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ASDA-A3 Installation
Revision December, 2017
2-9
2
Installation precautions
The ferrite ring is commonly used when peripheral devices (such as controller) are affected by
noise from conduction and radiation when the servo motor is in the Servo On state. The parasitic
capacitance between the cables in the wiring panel and the ground is typically small. As the
frequency of the signal increases (Servo On state), the resistance of the parasitic capacitance
becomes small enough to let common-mode current flow through. Normally, common-mode
current only leads to common-mode interference due to an unstable circuit caused by a poor
connection between the power circuit and ground. If the common-mode current flows through the
external cables, common-mode interference may also happen due to
electrical interference
caused by unstable electric potential.
The ferrite ring causes eddy current losses to high-frequency signal and transforms it into heat
when suppressing common-mode interference. The ferrite ring acts as a low-pass filter to
effectively suppress high-frequency noise and ensure the stability of the circuit while the
impedance to low-frequency signals is relatively small.
Winding several turns of wire onto the ferrite ring can increase inductance and the ability to filter
out high-frequency noise.
The suggested winding methods are shown below:
1. For A3-220V model (4.5 kW – 7.5 kW)
2. For A3-220V model (11 kW – 15 kW)
Note:
1. Please refer to Section 3.1.4 for the selection of the motor power cable.
2. Only the motor power cable or power cable can run through ferrite ring. If needed, please prepare extra
ferrite rings for grounding.
3. An EMI filter may be required for absorbing radiation when using a longer motor power cable.