Structure And Mode Of Action; Structure Of The Breaker Poles; Operating Mechanism Equipment; Basic Operating Equipment - ABB VD4X Instruction Manual

S T R U C T U R E A N D M O D E O F A C T I O N
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Structure and mode of action

276.5

3.1 Structure of the breaker poles

(Figures 3/1 to 3/3)
The horizontally arranged poles are mounted on
mounting plate 9 at the rear part of breaker
operating mechanism 1. The live parts of the
breaker poles are located in the insulating
material 11.
With the breaker closed, the current path leads
from breaker terminal 13 at the front via the
contacts in vacuum interrupter 15 to connecting
bar terminal 12 above or below the breaker pole.
Switching motions are initiated by actuating rod 17.
See figures 3/1 and 3/2.
The basic structure of a vacuum interrupter is
shown in figure 3/3.
3.2 Structure of the operating mechanism
(Figures 3/1 to 3/8)
The operating mechanism is of the stored-energy
spring type. The necessary operating energy is
stored ready for activation by charging the spring
energy storage mechanism. The stored-energy
spring operating mechanism essentially consists
of drum 23 containing the spiral spring, the
charging system, the latching and operating
mechanism and the linkages which transmit the
force to the breaker poles. In addition, there are
supplementary components such as releases and
the controls and instruments located on the front
of the enclosure.
The operating mechanism is fundamentally
suitable for auto-reclosing and, due to the short
motor charg ing times, also for multi-shot auto-
reclosing.
The spring energy storage mechanism is charged
by a motor (external activation and deactivation).
Emer gency manual operation with a charging
lever is possible.
There are rating plates with the main data of
the switching device at front plate 1.1 and at the
right of the mounting plate.

3.2.1 Operating mechanism equipment

1. Basic operating equipment:

• Shunt release OFF -Y2
• Shunt release ON -Y3
• Mechanical ON push-button (2)
• Mechanical OFF push-button (3)
• Rotational auxiliary switches -BGB for
annunciation purposes
• Auxiliary switch -S7 for fault signalization
• Mechanical position indicator (4)
• Mechanical charge-state indicator (8) for
the energy storage spring mechanism
• Mechanical operating cycle counter (5)
• Charging motor
• Micro-switches -S1 for switching of the
charging motor
• Mechanical interlocks
- Circuit-breaker/three position
disconnector
- Blocking magnet on circuit-breaker
(optional)
- Blocking of undervoltage release in the
case of earthing
2. Additional equipment:
• Second shunt release OFF -Y9
• Undervoltage release -Y4
• Indirect overcurrent release -Y7
Blocking magnet -Y1 mechanically blocks the
ON half shaft on failure or absence of control
voltage, and simultaneously uses the
corresponding rotational auxiliary switch
contact to interrupt the circuit of shunt release
ON -Y3.
The wiring diagram for the circuit-breakers can
be found in Figure 3/9 & 3/10.
3.3 Mode of action of the circuit-breaker
(Figures 3/1 to 3/8)
3.3.1 Charging of the spring energy storage
mechanism
To provide the necessary motive energy, the
spring energy storage mechanism is charged
either auto matically (external activation and
deactivation) by a charging motor or in
emergency manual operation with a vertical
15