Fagor QC-PDS, Hardware Manual

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Power line connection
6.
POWER LINE CONNECTION
Ma
ins conn
ecti
on cabl
es
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QC-PDS
HARDWARE
6.7.3 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.
See figure
F. H6/12
for properly installing the QC-PDS system with a IT-type
distribution diagram.
6.8 Mains connection cables
For more information on the mains connection cabling for the QC-PDS
system, see section
7.1 MAINS CONNECTION CABLES
.
F. H6/12
IT-type distribution diagram.
IT DIAGRAM
MANDATORY. With an IT distribution diagram, ALWAYS install the QC-
PDS system to mains through an isolating transformer.
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