Fagor DDS Series Hardware Manual page 236

   Power line connection
6.
238
DDS
HARDWARE
Ref.1912
· 236 ·
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.
SECONDARY
WINDING OF THE
LINE TRANSFORMER
OF THE PLANT
DIFFERENTIAL
BREAKER
MAINS
FILTER
DDS
SECONDARY
WINDING OF THE
LINE TRANSFORMER
OF THE PLANT
DIFFERENTIAL
BREAKER
MAINS
FILTER
DDS
F. H6/5
TT type distribution diagram.
MANDATORY. ·CORNER GROUNDED· type TT mains require installing
an isolating transformer.
See figure F. H6/5 for properly installing the DDS system in TT type
distribution network.
TT diagram
DIFFERENTIAL
DIFFERENTIAL
BREAKER
BREAKER
MAINS MAINS
FILTER FILTER
DDS DDS
L1
L2
L3
The DDS system is designed
to support phase-chassis
voltages under 300 V AC.
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.
L1
L2
L3