Connection Of The Pqfs In 4-Wire Mode - ABB PQFS Installation, Operation And Maintenance Instructions

6.8.2

Connection of the PQFS in 4-wire mode

Use the 4-wire connecting mode for installations where there is a need for neutral current
filtering and/or line to neutral balancing. In this mode, the active filter can compensate 15
individual harmonic components.
In order to connect the PQFS in 4-wire mode, follow the guidelines of
the exception that:
4.
6.
The cable lugs for the neutral cables should comply with:
Appropriate torque must be applied to ensure that cables are properly fixed.
Other points in the connection procedure are as per previous Section.
Remarks:
46 Electrical design and installation ç Manual Power Quality Filter PQFS
Figure 36: Position of the wires 'N' which cannot be removed
Make also a hole for the neutral cable in the protective cover noting the larger
section required for the neutral
Connect the three power cables and the neutral cable. Whereas the three power
cables can be connected as describes in item 6 of
has to be connected to the neutral connection point (Cf.
Figure 37: Connection of the neutral cable when using the PQFS in 4-wire mode
· Maximum lug width: in accordance with terminal width
· Minimum lug eye diameter: M8
· In case of regenerative loads (e.g. loads that may inject active energy to the
network, usually called 4Q-loads), it is very important to connect the PQF outside
the protection of this load. Indeed, consider
protection is installed for both the regenerative load and for the PQF. When the
load re-injects energy to the network and the mains protection trips, the whole
energy may be pushed into the PQF, which may damage it severely.
Section 6.8.1
Section 6.8.1, the neutral cable
Figure 37)
Figure 38 where a common
with
Figure 39