Delta CT2000 Series User Manual page 616

Chapter 19 EMC Standard Installation
Preface
Table of Contents
19-1 Introduction
19-1.1 What is EMC
19-1.2 EMC for AC Motor Drive
19-2 How to prevent EMI
19-2.1 Types of EMI: common-mode and differential mode noise
19-2.2 How does EMI transmit? (Noise transmission)
19-3 Solution to EMI: Grounding
19-3.1 Protective Grounding & Functional Grounding
19-3.2 Ground Loops
19-3.3 Earthing Systems
19-4 Solution to EMI: Shielding
19-4.1 What is Shielding?
19-4.2 How to Reduce EMI by Shielding?
19-5 Solution to EMI: Filter
19-5.1 Filter
19-5.2 Harmonic Interference
Preface
When an AC motor drive is installed in a noisy environment, radiated and/or conducted noise via signal and
power cables can interfere with the correct functioning, cause errors or even damage to the drive. To prevent this,
some AC motor drives have an enhanced noise resistance but the results are limited and it is not economical.
Therefore, an effective method would be finding the cause of the noise and use the right solution to achieve "no
emission, no transmission and no reception of noise". All three solutions should be applied.
Finding the Noise

Ascertain whether the error is caused by noise.

Find the source of the noise and its transmission path.

Confirm the signal and the source of noise
Solutions

Grounding

Shielding

Filtering
Chapter 19 EMC Standard Installation GuideCT2000 Series
19-1
Guide