Delta VFD-ED Series, User Manual

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Appendix A. EMC Standard Installation Guide | VFD-ED
A-4
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 to achieve 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 standard emission 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 levels.
1.2 EMC for AC Motor Drive
When an AC motor drive is put into operation, harmonic signal will occur at the AC drive’s power input and
output side. It creates a certain level of electromagnetic interference to the surrounding electrical devices and the
mains power network. An AC motor dive is usually applied in industrial environments with a strong electromagnetic
interference. Under such conditions, an AC drive could disturb or be disturbed.
Delta’s AC motor drives are designed for EMC and comply with EMC standard EN61800-3 2004. Installing
the AC motor drive accurately will decrease EMI influences and ensure long-term stability of the electricity system.
It is strongly suggested to follow Delta’s user manual for wiring and grounding. If any difficulties or problems arise,
please follow the instructions and measures as indicated in this EMC Standard Installation Guide.