GE Industrial Solutions EAK guidelines - Manual (Page 7)

3. EMISSIONS: RADIO-FREQUENCY CONDUCTED AND
R A D I A T E D
As far as the radio-frequency emissions are concerned, in the there has been a distinction made
between First and Second Environment, stating that the equipment has to be connected to a low-voltage
mains supply whether public or industrial, which could also supply domestics buildings.
For the first Environment, assuming that the mains is less than 500V of the type in accordance with
In case of IT mains, the capacity needed by EM1 filtering are not compatible with the system
protection. In these cases the safety precautions have priority on the EMC ones: it is advisable to call the
technical support service. In case of Restricted Distribution the limits are equal to the class A ones of
Standard EN5501 while in case of Unrestricted Distribution equal to class B for devices with rated current
less than 25A and class A for higher current.
Regarding the second Environment (A), which is the most frequently notable case, the limits are not defined
yet. As already anticipated in the conclusion at the first section, it is to refer to the limits, defined by the
curves A-B of standard EN5501 1.
In general, to have GE equipment in its limits, whether class A or B, it would be necessary both additional
devices (filters) and the respect of strict installation rules: in the next two paragraphs it will be given either
a guide to the selection of filters according to the type of the device, the cable-length between device and
motor and the size of the device and a list of rules in order to obtain an installation in accordance with EMC
additioned with sample diagrams.
Equally, for the radiated emissions, the does not fix limits (limits under consideration) for the
second Environment, while for the first it gives limitations equal to the EN5501 1, according to the functions,
the distribution and current size.
Both for the conducted and for the radiated emissions the relative measurements have been made, in order to
compare GE’s device to the prescribed limits, using the suitable filters and following the prescribed rules.
In the particular case of radiated emission, an additional attenuation has been considered, which can
be assumed when the device is mounted inside a cabinet and installed according the EMC rule, a condition
that is impossible to find during the EMC tests and measurements.