Pilz PSSnet GW1 MOD­-CAN Operating Manual page 15

Safety
3.1.1.6 Testing the EMC­compliance of an installation
You can use the list below to check that the installation of the Gateway is EMC­compliant.
Check
Are there areas with a high
probability of interference?
(e.g. computers running,
process control areas, dis­
tribution cabinets, cable
casing, frequency convert­
ers, hand­held radios etc.).
Are areas where com­
puters are running or
areas such as process
control rooms sufficiently
shielded from electromag­
netic coupling?
Does the cable layout take
into account the principles
of EMC compliance?
Is the supply voltage free
of interference?
EMC characteristics of in­
dividual units / all units
tested once installed?
Earthed parts connected
correctly?
Cable groups laid separ­
ately?
Are the shields connected
correctly?
Equipotential bonding car­
ried out?
Are inductive loads
switched?
24 VDC power supply?
Operating Manual PSSnet GW1 MOD­CAN
1002693­EN­03
Measures
EMC protection in these areas should be planned
with particular care.
If necessary shield the whole area.
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 possible,
avoid multiple crossovers.
Supplies with interference voltages should be fit­
ted with a mains filter.
Test EMC characteristics under operating condi­
tions, e.g. while hand­held radios are in use, or
HF frequency generators are close by. Test static
discharge with operating personnel, test mutual
interference between units under different operat­
ing conditions.
The connections between the units, racking bars,
earth conductors and shield bars are important.
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 fixings; protect the connection
from corrosion; connect the cabinet doors to the
body of the cabinet using earthing straps.
Separate cables into groups. Supply and signal
leads should be laid separately.
Use shielded cables for analogue and data leads;
use metallic plugs; connect cable shields to shield
bar at point of entry to cabinet; connect cable
shields over a wide surface area and with low im­
pedance.
If the installation extends over a wide area: lay
equipotential bonding cable.
Sufficient fuse protection should be used with in­
ductive loads
Power supplies must conform to EN
60742:9/1995, EN 60950­1:2006/A11:2009 or EN
50178: 10/97.
Done
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