ABB PQFS Installation, Operation And Maintenance Instructions page 51

•
The l (S2) terminal of the line 1 CT (L1, Red, U) must be connected to
terminal X21-2 of the filter.
•
The k (S1) terminal of the line 2 CT (L2, Yellow, V) must be connected to
terminal X214 of the filter.
•
The l (S2) terminal of the line 2 CT (L2, Yellow, V) must be connected to
terminal X21-5 of the filter.
•
The k (S1) terminal of the line 3 CT (L3, Blue, W) must be connected to
terminal X21-7 of the filter.
•
The l (S2) terminal of the line 3 CT (L3, Blue, W) must be connected to
terminal X21-8 of the filter.
−
The CT connection terminal X21 is located at the middle of the top plate of the
filter (Cf. Figure
Supply side
K = P1, L = P2, k = S1, l = S2
Figure 33: Basic CT connection example for a single unit active filter
Figure 34: Location of the CT connection terminal X21 in the PQFS
The terminal block X21 can handle control cable wiring with sections from 2.5 mm² to
10 mm².
In addition to the 6-wire CT cabling approach shown in
approach may also be used. This approach is illustrated in
secondary terminal to which the guard circuit is connected is interconnected between
the CTs and also on the filter terminal X21. One common cable is used for this terminal.
34).
L1 K L
K
L2
L3
k l
N
k
To X21.1/X21.2
To X21.4/X21.5
Manual Power Quality Filter PQFS  Electrical design and installation 51
L
K L
l
k l
To X21.7/X21.8
N L1
X21.1
X21.2
X21.3
X21.4
X21.5
X21.6
X21.7
X21.8
X21.9
CT connection terminal X21
Figure 33
Figure
Load side
L2 L3
PQF
above, a 4-wire
35. In this case the CT