Fagor QC-PDS - 6.4 Isolating transformer or auto-transformer

 Power line connection
POWER LINE CONNECTION
Isolating transformer or auto-transformer
6.
Ref.2003
· 205 ·
QC-PDS
HARDWARE
6.4 Isolating transformer or auto-transformer
When the mains voltage must be isolated or adapted to the levels required
by the QC-PDS system, it may be connected through an isolating
transformer or an auto-transformer. This element will also help reduce the
amount of harmonics on the line although it will not ensure compliance with
the EC standard.
The following figure shows the position where the transformer or auto-
transformer must be installed within the whole power line connection
system:
It is also highly recommended
to use auto-transformers instead of
isolating transformers when only an adaptation of the working voltages is
required.
MANDATORY. When installing an isolating transformer, the secondary must
a have a star (Y) configuration with access to the mid point
which must be
connected to ground.
F. H6/4
Position of the isolating transformer or auto-transformer.

M A I N S
C O N N E C T I O N
Q C - P D S
N
L 1 L 2 L 3
L 1 L 2 L 3
- S 1
M A I N
S W I T C H
- S 1
M A I N
S W I T C H
M A I N S F I L T E R
M A I N S F I L T E R
Q C - P D S
- Q 1
D I F F E R E N T I A L
B R E A K E R
- Q 1
D I F F E R E N T I A L
B R E A K E R
- F i
F U S E S
- F i
F U S E S
M A I N S
C O N N E C T I O N
MANDATORY. When using transformers or auto-transformers, the -KM1
power contactor (required only for QC-RPS-  -  power supplies) must be
connected between the main filter and the QC-PDS system and never on
line of entry to the transformer or auto-transformer.
WARNING. Not complying with the previous indications could cause the
QC-PDS system to perform poorly.