Emc Driver

http://www.delta.com.tw/industrialautomation/

AC Motor Drives

EMC Standard Installation Guide
EMC Compliance Practice

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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 anenhanced 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 itstransmission path. Confirm the signal and the source of noise

Solutions
   Grounding Shielding Filtering

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Table of Contents
Preface ....................................................................................................................i Table of Contents....................................................................................................ii Chapter 1Introduction............................................................................................ 1 1.1 What is EMC ............................................................................................. 1 1.2 EMC for AC Motor Drive ........................................................................... 1 Chapter 2 How to prevent EMI............................................................................... 2 2.1 Types of EMI: common-mode and differential mode noise ....................... 2 2.2 How does EMI transmit? (Noise transmission) ......................................... 2 Chapter 3 Solution to EMI: Grounding ................................................................... 4 3.1 Protective Grounding & Functional Grounding..........................................4 3.2 Ground Loops ........................................................................................... 5 3.3 Earthing Systems ...................................................................................... 5 Chapter 4 Solution to EMI: Shielding ..................................................................... 9 4.1 What is Shielding?.................................................................................... 9 4.2 How to Reduce EMI by Shielding?.......................................................... 10 Chapter 5 Solution to EMI: Filter .......................................................................... 12 5.1 Filter ........................................................................................................ 12 5.2 HarmonicInterference............................................................................. 14

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Chapter 1 Introduction
1.1 What is EMC?
Electromagnetic Compatibility (EMC) is the ability of an electrical device to function properly in electromagnetic environments. It does not emit electromagnetic noise to surrounding equipment and is immune to interference from surrounding equipment. The goal is toachieve high immunity and low emission; these two properties define the quality of EMC. In general, electrical devices react to high and low frequency phenomena. High frequency phenomena are electrostatic discharge (ESD); pulse interference; radiated electromagnetic field; and conducted high frequency electrical surge. Low frequency phenomena refer to mains power harmonics and imbalance. The standardemission and immunity levels for compliance depend on the installation location of the drive. A Power Drive System (PDS) is installed in an industrial or domestic environment. A PDS in a domestic environment must have lower emission levels and is allowed to have lower immunity levels. A PDS in an industrial environment is allowed to have higher emission levels but must have more severe immunity...