Bosch Rexroth Tightening System 350 - Grounding

3 608 878 300 Tightening Technology | Bosch Rexroth AG 99/641
System 350 | 3 608 878 300/2019-03
4.3.2.1 Cable protection switch compact system
The compact system has built-in fuses. Pre-fuses are therefore only required for cable protection. The
minimum protection values are listed in Table 4–21.
4.3.3 Grounding
4.3.3.1 Tightening system
The tightening system is grounded via the existing system components. Due to leakage currents from
EMC protective measures, card racks or system boxes must be grounded with a gr-ye cable having a
cross section of at least 10 mm
2
. The connection must be firmly connected. (Requirement from EN50178,
issue 04/98, chapter 5.3.2.1 as well as chapter 5.2.11.1).
The hand-held nutrunners/tightening spindles are sufficiently grounded via their connection cables. The
lines are generally equipped with an EMC shield to protect against impermissible electromagnetic
influences. Coupled interferences are conducted to ground via these shields.
When these guidelines are followed, the tightening systems comply with valid directives and do not
require any further measures.
System box grounding
The design of the system boxes results in a special grounding feature. The permanently connected
10-mm
2-
ground cable on the bottom of the system box is supplemented by grounding through the power
supply connection line. The same must also be available at all times due to safety reasons.
Two studs are included on the bottom of the system boxes to simplify the installation of systems made up
of several system boxes.
This allows interconnecting several system boxes to the permanently connected 10-mm
2-
ground cable.
Fig. 4–26: Linking system boxes
Table 4–21: depending on the nominal voltage
Components Nominal voltage Power switch setting
CS351 compact system 230 V 5,2 A
120 V 10 A
NOTICE
Interference currents
If interference currents are to be expected, a return way has to be provided for interferences.
 Often, installation of the system boxes at the steel components of the system is sufficient to
ensure discharge. If this installation is insulated (e.g. busbar system) additional discharge has to
be provided. This may include braid strands or large grounding surfaces. These have to be
positioned as close (electrically) as possible at the workpiece. In this case, discharge via the
mains connection alone is not sufficient!
(1) 10 mm
2
gn-ge
(2) System grounding
(1)
(2)