Electrical Interconnection Of Pqfs Enclosures - ABB PQFS Installation, Operation And Maintenance Instructions

Figure 43: Four wires CT wiring approach that may be used with a single unit PQFS active filter
In case a filter system consists of more than one unit, all units have to be supplied with
the CT measurement information. This is done by cabling the CTs in a daisy chain
fashion between the different units. This is illustrated in

6.11 Electrical interconnection of PQFS enclosures

This section explains how to electrically interconnect different PQFS enclosures.
Figure 44
filter enclosures.
The interconnection description is given in
L1 K
L2
Supply side
L3
N
K = P1, L = P2, k = S1, l = S2
shows schematically which interconnections have to be made between two
AC power supply
L
N
Output filter
Master Unit
Figure 44: Overview of the connections to be made between two filter enclosures
L
K L
K
To X21.2 To X21.6
To X21.4
...
Preload
resistor
(1)
(2)
Unit 1
Power Unit 2
Power Unit 1
Master or Slave Unit
Table 21.
Manual Power Quality Filter PQFS ç Electrical design and installation 51
Load side
L
L1 L2 L3
N
X21.1
X21.2
X21.3
PQF
X21.4
X21.5
X21.6
Section 6.11.3.
L
N
Output filter
Unit 2