Compartments In The Panels; Busbar Compartment; Circuit-Breaker Compartment - ABB UniGear ZS1 Instruction Manual

3.3 Compartments in the panels

Figure 3: Example of insulating covers

3.3.1 Busbar compartment

The busbars 3 (figure 2) have a flat cross-section made of copper and are laid in sections from panel
to panel. For higher rated currents (3150, 3600 and 4000 A), the busbars have a D-shaped cross-
section.
According to the current rating, either single or double configuration is used. They are held by flat
branch conductor 2 and, if installed, by busbar bushings 29. No special connection clamps are needed.
Busbars and branch conductors for 17.5 kV and 24 kV are insulated by means of shrink-on sleeves.
The bolt connections in the 17.5 kV and 24 kV busbars system are covered by insulating covers 58
(figure 3). The busbars for 12 kV units up to 2000 A are without any covers. Flat busbars 2500 A and
D-shaped busbars 3150, 3600 and 4000 A are insulated and the connections are covered.
By means of bushing plates 28 and busbar bushings 29 (figures 61, 62) partitions can be created
between panels. These partitions are necessary for higher rated short-time currents – see the following
table.
Rated voltageRated short-time withstand currentPartitions
12/17,5 kV
24 kV
Marine version
1) In these panels, busbar bushing and bushing plates don't need to be mounted. The dynamic strength of the busbar system is sufficient.
2)
In these panels, busbar bushing and bushing plates must be mounted in every third panel only when you have the sequence of 800
and 1000mm wide. If these panels are positioned between 650mm wide panel they don't need bushings because the dynamic strength
of the busbar system is sufficient.
3)
In these panels, busbar bushing and bushing plates must be mounted in every panel.
According to customer requirements, this separation into individual panels by means of busbar
bushings 29 and bushing plates 28 (figures 61, 62) can also be provided in switchgear panels where
it is not technically necessary.
Top-mounted boxes with busbar earthing switches, or busbar voltage transformers can be placed
above the units.

3.3.2 Circuit-breaker compartment

The circuit-breaker compartment contains all the necessary equipment for reciprocal operation of the
withdrawable part and the panel. Like the busbar compartment, it is metallically partitioned on all sides.
The tulip isolating contacts 5, together with the fixed isolating contacts, are located in mounting plate
12 (figure 2).
The metal shutters 12.1/12.2, covering the insertion openings, are also included. The shutters are
opened by means of actuating bars 13.16 (figure 6) of the withdrawable circuit-breaker part when
inserting into the service position, and are closed when the latter is removed.
In the test/disconnected position of the withdrawable part, partitioning by separation is established in
the main current circuit. Connection of the control wiring, required for test purposes, need not be
interrupted when in the test/disconnected position.
25 kA
31,5 kA
40 kA, 50 kA
25 kA, 31,5 kA
All ratings
No 1)
2)
Every third panel
3)
Every panel
No 1)
Every panel 3)
58.5
58
9