Installing Signal Lines And Signal Cables - Bosch REXROTH EFC 3600 Instruction Manual

Bosch Rexroth AG
EMC Measures for Design and Installation
The best solution is to use a zinc-coated mounting plate. Compared to a lacquered
plate, the connections in this case have a good long-time stability.
Connection Elements
For lacquered mounting plates, always use screw connections with tooth lock washers
and zinc-coated, tinned screws as connection elements. At the connection points, re‐
move the lacquer so that there is safe electrical contact over a large surface area. You
achieve contact over a large surface area by means of bare connection surfaces or
several connection screws. For screw connections, you can establish the contact to
lacquered surfaces by using tooth lock washers.
Metal Surfaces
Always use connection elements (screws, nuts, plain washers) with good electrocon‐
ductive surface.
Bare zinc-coated or tinned metal surfaces have good electroconductive properties.
Anodized, yellow chromatized, black gunmetal finish or lacquered metal surfaces have
bad electroconductive properties.
Ground Wires and Shield Connections
For connecting ground wires and shield connections, it is not the cross section but the
size of contact surface that is important, as the high-frequency interference currents
mainly flow on the surface of the conductor.
6.3

Installing Signal Lines and Signal Cables

Line Routing
For measures to prevent interference, see the Project Planning Manuals of the respec‐
tive device. In addition, we recommend the following measures:
● Route signal and control lines separately from the power cables with a minimum dis‐
tance of 100 mm or with a grounded separating sheet. The optimum way is to route
them in separate cable ducts. If possible, lead signal lines into the control cabinet at
one point only.
● If signal lines are crossing power cables, route them in an angle of 90° in order to
avoid interference injection.
● Ground spare cables, that are not used and have been connected, at least at both
ends so that they do not have any antenna effect.
● Avoid unnecessary line lengths.
● Run cables as close as possible to grounded metal surfaces (reference potential).
The ideal solution are closed, grounded cable ducts or metal pipes which, however,
is only obligatory for high requirements (sensitive instrument leads).
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DOK-RCON01-REX*F*UL***-IN01-EN-P
Rexroth Frequency Converters