Electromagnetic Compatibility (EMC)
Installation Manual PSSuniversal
21262-EN-07
14
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For varnished or anodised metal parts you should use special contact plates or remove
the protective coating.
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Install an earth bar for the cable shields.
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The earth bar can also be used as the ground conductor bar.
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Connect the earth bar or earth conductor to the mounting plate over a wide surface
area and with low impedance. If the bar is to be used as the earth conductor, comply
with the latest regulations for earthing the bar.
3.2.8
Lighting in the control cabinet
Use low interference panel lighting for inside the control cabinet.
3.3
Testing the EMC-compliance of an installation
You can use the list below to check that the installation of the PSSu is EMC-compliant.
Check
Action
Done
Are there areas with a high
probability of interference?
(e.g. computers running,
process control areas, distri-
bution cabinets, cable cas-
ing, frequency converters,
hand-held radios etc.)
EMC protection in these areas should be
planned with particular care.
Are areas where computers
are running or areas such as
process control rooms suffi-
ciently shielded from electro-
magnetic coupling?
If necessary shield the whole area.
Does the cable layout take
into account the principles of
EMC compliance?
Some important points: Lay cables close to
earth, keep clear of other electrical equipment,
keep cables in ducts separate from other parts
of the installation, keep cables as short as pos-
sible.
Is the supply voltage free of
interference?
Supplies with interference voltages should be
fitted with a mains filter.
EMC characteristics of indi-
vidual units / all units once
installed?
Test under operating conditions, e.g. while
hand-held radios are in use, or HF frequency
generators are close by. Test static discharge
with operating personnel, test mutual interfer-
ence between units under different operating
conditions.
Earthed parts connected
correctly?
Most important are the connections to the
PSSu housing, racking bars, earth conductors
and earth bars; inactive metal parts should be
connected over a wide surface area and
earthed at a central point; with insulated metal:
Remove insulation or use special contact fix-
ings; protect the connection from corrosion;
connect the cabinet doors to the body of the
cabinet using earthing straps
