User's Manual Part 1

Table Of Contents
RF300 system planning
4.6 EMC Directives
SIMATIC RF300
System Manual, 09/2007, J31069 D0166-U001-A5-7618
73
4.6.2 What does EMC mean?
The increasing use of electrical and electronic devices is accompanied by:
Higher component density
More switched power electronics
Increasing switching rates
Lower power consumption of components due to steeper switching edges
The higher the degree of automation, the greater the risk of interaction between devices.
Electromagnetic compatibility (EMC) is the ability of an electrical or electronic device to
operate satisfactorily in an electromagnetic environment without affecting or interfering with
the environment over and above certain limits.
EMC can be broken down into three different areas:
Intrinsic immunity to interference:
immunity to internal electrical disturbance
Immunity to external interference:
immunity to external electromagnetic disturbance
Degree of interference emission:
emission of interference and its effect on the electrical environment
All three areas are considered when testing an electrical device.
The RFID modules are tested for conformity with the limit values required by the CE and
RTTE guidelines. Since the RFID modules are merely components of an overall system, and
sources of interference can arise as a result of combining different components, certain
guidelines have to be followed when setting up a plant.
EMC measures usually consist of a complete package of measures, all of which need to be
implemented in order to ensure that the plant is immune to interference.
Note
The plant manufacturer is responsible for the observance of the EMC guidelines; the plant
operator is responsible for radio interference suppression in the overall plant.
All measures taken when setting up the plant prevent expensive retrospective modifications
and interference suppression measures.
The plant operator must comply with the locally applicable laws and regulations. They are
not covered in this document.