Baumuller b maXX BM3400 Series - 6.8.2 Earthing

T 6 Installation
• The ground connection converter/ground plane must be as short as possible (<30cm) and must be
fine-wired. Use great cross-sections (>10mm).
• Connect the PE-connection on the load side of the filter with low-impedance to the mounting board.
Ideal is a zinc-plated sheet metal a ngle or a HF-grounding band .
• Jamming transmitter as relais, transformers, chokes and noise sensitive modules as microcontrollers,
bus systems and so on should have a t least 20cm clearance to the converter and its cabling.
• Avoid reserve loops at extra-long cables.
• Ground reserve cables always on both ends (additional screening effect, avoid capacitive coupled da n-
gerous c ontact voltages).
• Don’t switch mains filters parallel. If several devices are operated in a switching cabinet, the use of
devices without internal mains filters is recommended. In this case a common external mains filter
must be used.
• Don’t connect mains filters of the same type of construction in series - the attenuation characteristics
will not be approved.
• Suppress each drive individually from interferences. In case at all drives interferrences must be com-
monly suppressed, do not interrupt the screens between the converter and the mains filter. This means,
that the screened cab les may not be interrupted by fuses nor by contactors or others, except of possibly
necessary mains chokes.
6.8.2 Earthing
• In order to minimize the influence of interferences with higher frequencies, which arise d ue to the op-
eration of the converter, for purposes of EMC the classical star-connected grounding is insufficient. A
reference surface is necessary, which is connected to the grounding potential of the devices (i.e. metal-
lic bright mounting board and cabinet parts) over a large area.
• Mount the converter, the associated mains filter and the plane screening contact of the motor cable on
the same reference surface.
• In order to avoid ground loops you must lead all grounding contactors and screens close to ground.
• Ground the controller reference potential of the converter. Execute the connection with the greatest
possible cross section and with a short cable (<30cm).
• Remove insulation layers such as paint, adhesives or the like from the ground connections. If necessary
use serrated lock washers (DIN 6798) in order to penetrate the surface and therewith achieve a durable
conductive contact. In order to avoid corrosion of ground connections select appropriate metal pair-
ings (c onsider electromotive series). Keep electrolytes away from the connection by using a protective
coating (e.g. grease).
• Always connect the screens on both ends plane and highly conductive with ground. Only like this
magnetic or high-frequency interference fields ca n be attenuated in its actions. When having problems
with ground loops (e.g. double-grounding of the setpoint conductor screening) the receiver-side should
be connected directly a nd the transmitter-side capacatively.
• Connect the external cable screens when passing through walls, which separate different EMC ranges.
Cables, which are guided through walls of screening c abinets without making provisions for e.g. filter-
64 Instrution Manual b maXX ® BM3400
from 206 Doument No.: 5.07013.03 Baumueller Kamenz GmbH