Fagor 2104, Быстрая справка

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Fagor M odular Drives and Motors Q uick R eference. Ref.2104 MQR-71/84
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 kinds of TN diagrams depending on the relative
position of the neuter wire (N) and the protection wire (PE):
 TN-S diagram where the neuter wire (N) and the protection wire
(PE) are different in the entire diagram.
 TN-C-S diagram where the neuter and protection functions are
combined in a single wire (PEN) in part of the diagram.
 TN-C diagram where the neuter and protection functions are
combined in a single wire (PEN) in the entire diagram.
IT diagram
Distribution diagram that has no direct connection to ground and the
conductive parts of the installation are connected to ground.
With IT type distribution diagrams, the differential breaker is used
assuming that the capacitance of mains with respect to ground is
large enough to ensure that a minimum fault current flows with the
same magnitude as that of the operating differential current assigned.
Otherwise, its use is not necessary.
TT diagram
Distribution diagram that has a point directly connected to ground and
the conductive parts of the installation are connected to a ground point
independently from the ground electrode of the power supply system
.
INFORMATION. The DDS system may be connected
directly, through a transformer or auto-transformer in
mains with a TN type distribution diagram.
MANDATORY. With an IT distribution diagram, always in-
stall the DDS system to mains through an isolating trans-
former.
INFORMATION. Note that with an IT type distribution
diagram, mains can also be controlled through an isolation
watching device. Both protection measurements are
compatible with each other.
i
DDS DDS
L1
L2
L3
DIFFERENTIAL
BREAKER
DDS
SECONDARY
WINDING OF THE
LINE TRANSFORMER
OF THE PLANT
DIFFERENTIAL
BREAKER
DIFFERENTIAL
BREAKER
MAINS
FILTER
PEN
MAINS
FILTER
MAINS
FILTER
TN-C diagram
i
MANDATORY. ·Corner grounded· type TT mains
require installing an isolating transformer.
DDS
L1
L2
L3
SECONDARY
WINDING OF THE
LINE TRANSFORMER
OF THE PLANT
DIFFERENTIAL
BREAKER
MAINS
FILTER
L1
L2
L3
DDS
DIFFERENTIAL
BREAKER
SECONDARY
WINDING OF THE
LINE TRANSFORMER
OF THE PLANT
MAINS
FILTER
IT diagram
L1
L2
L3
DDS
DIFFERENTIAL
BREAKER
SECONDARY
WINDING OF THE
LINE TRANSFORMER
OF THE PLANT
MAINS
FILTER
DDS DDS
L1
L2
L3
DIFFERENTIAL
BREAKER
DDS
SECONDARY
WINDING OF THE
LINE TRANSFORMER
OF THE PLANT
DIFFERENTIAL
BREAKER
DIFFERENTIAL
BREAKER
MAINS
FILTER
MAINS
FILTER
MAINS
FILTER
The DDS system is designed to
support phase-chassis voltages
under 300 Vac.
It must be ensured that there is
no voltages over the indicated
value if an isolating transformer
is not installed; i.e. if the DDS
system is connected directly to
mains or through an auto-
transformer.
Otherwise, protection elements
must be installed to avoid
reaching excessive voltages
.
TT diagram