8 Installation
NivuLink Compact - Document revision 02 / 06.08.2020
page 43
8.5.1.3 Screening
General
The use of screened cables reduces electromagnetic influence and hence improves the sig-
nal quality. Measurement errors, data transmission errors and errors due to overvoltage can
be avoided.
Connect cable screen to ground potential!
Consistent screening is absolutely necessary to guarantee technical specifications regard-
ing the measurement accuracy. Connect cable screen and ground potential even at the
cable entry of the switching cabinet or the housing. This measure will discharge induced
interferences and keeps them away from the installed units.
Improve screening using a large contact area!
Screening is improved by using a low-resistance connection between screen and ground
potential. To achieve this use a large contact area to connect the screen e.g. by using the
WAGO Screen Connection System. This system is recommended particularly for systems
with a wide spread with compensating currents flowing or where higher impulse-type cur-
rents (e.g. due to atmospheric discharge) may occur.
Keep data and signal lines away from interfering sources!
Always lay data and signal lines separated from any high current cables and other sources
inducing high electromagnetic emission (e.g. frequency converters or drives).
Bus Lines
The screening of the bus line is described in the according installation guidelines and stand-
ards of the bus system.
Signal Lines
The bus terminals for analog signals as well as some interface bus terminals are equipped
with terminal clamps for screening.
Use screened signal lines!
For analog signals and for bus terminals which are equipped with terminal clamps for
screening use exclusively screened signal lines. This is the only way to make sure that the
accuracy and interference immunity specified for the according bus terminal are achieved
even in case of interferences affecting the signal cable.
WAGO Screen Connection System
The WAGO Screen Connection System consists of screen spring connections, buses and
various mounting bases which can be used for many different mounting tasks.
