Ferrite Ring - Delta ASDA-A3 Series User Manual

ASDA-A3

2.6 Ferrite ring

The ferrite ring suppresses high-frequency noise, which can reduce high-frequency interference
in the power cable, signal cable, and connectors. The ferrite ring is usually made of Mn-Zn
ferrite. The impedance of the ferrite ring varies with frequency. Normally, its impedance is
relatively small to low-frequency signals; however, when the frequency of the signal increases,
the impedance increases dramatically, which optimizes signal transmission. Suggested ferrite
ring models:
Ferrite ring model
ASD-ACFC7K00
Note: in the servo drive model column,  represents the model code.
Installation precautions
The ferrite ring is commonly used when peripheral devices (such as the 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, but as the frequency of the signal increases (Servo On state), the resistance of the
parasitic capacitance becomes small enough for the common-mode current to 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 signals and transforms them 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.
ASD-A3-4523-, ASD-A3-5523-, ASD-A3-7523-, ASD-A3-1B23-,
ASD-A3-1F23-
ASD-A3-2043-, ASD-A3-3043-, ASD-A3-4543-, ASD-A3-5543-,
ASD-A3-7543-, ASD-A3-1B43-, ASD-A3-1F43-
Applicable servo drive model
Installation
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