Danaher Motion Standalone MMC, Руководство по оборудованию

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162 Standalone MMC Hardware Manual
CE and EMC Guidelines
version 15.1
Danaher Motion
Figure 11-1: Safety Margin
In addition to conducted and radiated immunity, products must also be capable of
withstanding:
• Electrostatic discharges (ESD)
• Conducted fast transient voltages
The discharge spark generated from ESD can easily damage electronic components.
The conducted fast transient voltages are induced in cables laid in close proximity to
other cables in which large inductive loads are switched (such as relays, contactors,
and AC motor starters). This is a good example of what can happen to sensitive
control and signal cabling connected to drives when poorly installed in enclosures on
industrial sites.
11.4 Classes of EMC Operating Environments
Before the correct level of EMC can be designed into equipment, the EMC operating
environment must be defined. For example in industrial locations where high power
equipment is in use, high levels of background electrical noise would be expected
when compared to a household or office environment. Since it is more expensive to
reduce the emissions from higher power equipment than to increase the immunity, the
emission limits allowed in industrial environments are higher than for household or
office environments. Vice versa for immunity because of the higher emission limits in
industrial environments, the immunity requirements are more strict than for the
household or office environment. Hence in order to achieve EMC between different
equipment, it is essential to know what EMC operating environment it is to be installed
in, and to compare the installation environment to the environment for which it was
designed.
Today using generic EMC standards, two environments are defined:
1. Industrial
2. Residential, commercial, and light industrial
The environments are locations defined on the basis of whether the AC supply is
shared with other locations or is buffered from them with a distribution transformer. If
your location is buffered via a distribution transformer, then you are in an industrial
environment. If you share your AC supply with a neighboring location, then you are in
Compatibility Levels
Safety Margin
Immunity Level
Emission Level