Emc Guidelines; Electro-Magnetic Compatibility (Emc) - Siemens MICROMASTER Eco Reference Manual

ECO REFERENCE MANUAL
12.

EMC GUIDELINES

All electronic and electrical equipment generate
unwanted signals. These signals can be emitted
from the product either via cables that are
connected to the product (Input, output, control
signals etc.) or via electromagnetic radiation 'radio
transmission'. These signals can be received by
other products (via the same routes) and can
interfere with the correct operation of the product.
Micromaster
Control
Supply
Micromaster
Control
Supply
Any particular product gives out a certain level of
emissions, and has a certain level of immunity to
incoming signals from other products. If the
immunity of all products is higher than their
emissions, there is no problem. If the immunity is
lower, severe problems can occur, causing quality
problems, damage, or in extreme cases injury.
Electro-magnetic Compatibility (EMC) concerns
how equipment works together; Electro-magnetic
Interference (EMI) refers to the unwanted signals
themselves.
Output
Emissions
Output
Immunity to
Emissions
EMI has become a more serious problem recently
as more electronic systems (which may prove to
have low immunity) are used in industrial
applications, and as power electronic products such
as drives, generate high frequency signals which
can produce high levels of interference.
ELECTRO-MAGNETIC
COMPATIBILITY (EMC)
All manufacturers/assemblers of electrical
apparatus which performs a complete intrinsic
function which is placed on the European market
as a single unit intended for the end user must
comply with the EMC directive EEC/89/336 after
January 1996. There are three ways by which the
manufacturer/assembler can demonstrate
compliance:
• Self-Certification
This is a manufacturer's declaration that the
European standards applicable to the
electrical environment for which the apparatus
is intended have been met. Only standards
which have been officially published in the
Official Journal of the European Community
can be cited in the manufacturer's declaration.
• Technical Construction File
A technical construction file can be prepared
for the apparatus describing its EMC
characteristics. This file must be approved by
a 'Competent Body' appointed by the
appropriate European government
organisation. This approach allows the use of
standards which are still in preparation.
• EC Type-Examination Certificate
This approach is only applicable to radio
communication transmitting apparatus.
The MICROMASTER Eco and MIDIMASTER Eco
units do not have an intrinsic function until
connected with other components (e.g. a motor).
Therefore, the basic units are not allowed to be
CE marked for compliance with the EMC
directive. However, full details are provided of
the EMC performance characteristics of the
products when they are installed in accordance
with the wiring recommendations in the Wiring
Guidelines at the end of this section.
EMC
12-1