Fagor QC-PDS, Руководство по оборудованию

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Power line connection
6.
POWER LINE CONNECTION
Distribu
tion dia
grams
214
Ref.2003
· 212 ·
QC-PDS
HARDWARE
6.7 Distribution diagrams
The distribution diagram being used must be taken into consideration in
order to determine the characteristics of the protection means against
electrical shocks, in case of failure (indirect contacts) and against over-
current, as well as the specifications of the devices in charge of such
functions. The distribution diagrams are established according to the
ground connections of the distribution network or of mains, on one hand,
and the of the grounds of the receiving installation on the other.
Depending on the electric energy distribution networks, there are three
types of diagrams: TN, TT and IT.
Depending on the type of distribution diagram, the cabling in the electrical
cabinet will vary considerably.
6.7.1 TN diagram
Distribution diagram that has a point directly connected to ground and the
conductive parts of the installation are connected to this point through
ground protection conductors. This type of mains admits loads between
one or several phases and the neuter.
There are three sub-types of TN diagrams, depending on the relative position
of the (N) neutral conductor and the ground protection conductor (PE):

TN-S , where the neutral conductor (N) and the ground protection
conductor (PE) are different throughout the entire diagram.

TN-C-S , where the functions of the neutral and the protection are
combined in a single conductor (PEN) in a part of the diagram.

TN-C , where the neutral and protection functions are combined in a
single conductor (PEN) throughout the entire diagram .
See figure
F. H6/10
for properly installing the QC-PDS system with a TN-C-
type distribution diagram.
IMPORTANT NOTE
.
The diagrams provided under this section have
intentionally not shown the - KM1 power contactor and the choke that
must be connected to the main filter, which are only required (both) for
QC-PDS systems with QC-RPS-

-F

regenerative power supplies.
F. H6/10
TN-C-type distribution diagrams.
TN-C DIAGRAM
INFORMATION. The QC-PDS system may be connected directly, through
a transformer or auto-transformer in mains with a TN-type distribution
diagram.
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