n
In special use cases you should appoint special EMC actions.
– Consider to wire all inductivities with erase links.
– Please consider luminescent lamps can influence signal lines.
n
Create a homogeneous reference potential and ground all elec-
trical operating supplies when possible.
– Please take care for the targeted employment of the grounding
actions. The grounding of the PLC serves for protection and
functionality activity.
– Connect installation parts and cabinets with your PLC in star
topology with the isolation/protected earth conductor system.
So you avoid ground loops.
– If there are potential differences between installation parts and
cabinets, lay sufficiently dimensioned potential compensation
lines.
Electrical, magnetically and electromagnetic interference fields are
weakened by means of an isolation, one talks of absorption. Via the
isolation rail, that is connected conductive with the rack, interference
currents are shunt via cable isolation to the ground. Here you have to
make sure, that the connection to the protected earth conductor is
impedance-low, because otherwise the interference currents may
appear as interference cause.
When isolating cables you have to regard the following:
n
If possible, use only cables with isolation tangle.
n
The hiding power of the isolation should be higher than 80%.
n
Normally you should always lay the isolation of cables on both
sides. Only by means of the both-sided connection of the isolation
you achieve high quality interference suppression in the higher
frequency area. Only as exception you may also lay the isolation
one-sided. Then you only achieve the absorption of the lower fre-
quencies. A one-sided isolation connection may be convenient, if:
– the conduction of a potential compensating line is not possible.
– analog signals (some mV respectively µA) are transferred.
– foil isolations (static isolations) are used.
n
With data lines always use metallic or metallised plugs for serial
couplings. Fix the isolation of the data line at the plug rack. Do not
lay the isolation on the PIN 1 of the plug bar!
n
At stationary operation it is convenient to strip the insulated cable
interruption free and lay it on the isolation/protected earth con-
ductor line.
n
To fix the isolation tangles use cable clamps out of metal. The
clamps must clasp the isolation extensively and have well contact.
n
Lay the isolation on an isolation rail directly after the entry of the
cable in the cabinet. Lead the isolation further on to your PLC and
don't lay it on there again!
CAUTION!
Please regard at installation!
At potential differences between the grounding points,
there may be a compensation current via the isolation con-
nected at both sides.
Remedy: Potential compensation line
Isolation of conductors
VIPA System SLIO FM 050
Basics and Assembly
Installation guidelines
HB300 | FM | 050-1BA00 | GB | 15-11
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