14
Switching operation
The sequence of actions involved in various
switching operations are described in this
section. Refer to Figure 7: Pole assembly on
page 14 and Figure 8: Magnetic-actuator
operating mechanism on page 15.
When a closing command is initiated, the
capacitors (106.2) power the magnetic
actuator (101.0). This process is monitored by
the controller board (105.0). The electrical
current in the coil (101.3) generates a
magnetic field. An attractive force causes the
anchor (101.4) moving upwards.
The coupling rod (62.8) moves upwards by
compressing the opening springs (64.0) by
means of the jack shaft (63.0). The contact
pressure springs (49.0) are compressed and
the insulating couplers (48.0) are moved
upwards. Through the angled levers (48.6)
the contacts in the vacuum interrupter (30.0)
are closed.
The forces that occur when the action of the
insulating coupler (48.0) is converted into the
action of the moving contact along the axis of
the vacuum interrupter are absorbed by the
guide link (48.9) that pivots on the moving-
end pole head and the eye bolt.
In the closed state, the necessary contact
pressure is maintained by the contact
pressure springs (49.0) and the atmospheric
pressure. The magnetic actuator maintains a
stable closed position without supplemental
energy input. The contact pressure spring
automatically compensates for arc erosion,
which is very small.
When a opening command is initiated, the
capacitors (106.2) power the magnetic-
actuator coil (101.3) with a reverse current.
This opposes the attractive force between the
magnetic actuator (101.0) and the
permanent magnet. Due to the energy stored
in the contact pressure springs (49.0) and the
opening spring (64.0), the magnetic-
actuator’s anchor (101.4) is pushed
downwards. This opening process is
supported by the opening spring (64.0). In
the OPEN position the opening spring assures
that the ambient pressure does not close the
contacts in the vacuum interrupters (30.0).
Operating mechanism
The operating mechanism is comprised of the
mechanical and electrical components
required to:
1. Charge the capacitors for providing
sufficient electrical energy to move the
magnetic actuator and close or open the
circuit breaker.
2. Mechanisms to release closing and
opening actions.
3. Means of transmitting force and motion
to each of the three vacuum interrupters.
4. Operate all these functions automatically
through the capacitors (106.2), the
controller board (105.0). auxiliary switch
3SV9 (68.0), the lock out switch (114.0)
and the opening spring (64.0).
5. Provide indication of the circuit breaker
status (OPEN/CLOSED), indicate capacitor
energy status (green LED indicates ready,
yellow LED indicates OPEN operation is
possible and red LED indicates error) and
number of operations.
Figure 7: Pole assembly
Item
Description
16.0
Pole support
channels
16.1
Post insulator
20.0
Fixed-end pole head
27.0
Fixed-end connection
pad
28.0
Strut
28.1
Centering ring
29.0
Moving-end
connection pad
29.1
Flexible shunt
29.2
Terminal clamp
30.0
Vacuum interrupter
31.0
Fixed contact
36.0
Moving contact
40.0
Moving-end pole
head
48.0
Insulating coupler
48.6
Angled lever
48.9
Guide link
49.0
Contact pressure
spring
60.0
Mechanism housing
62.8
Coupling rod
62.9
Coupling link
63.0
Jack shaft
64.3
Lever
60.0
48.0
49.0
64.3
48.6
62.9
16.0
16.0
16.1
16.1
20.0
40.0
28.1
28.0
63.0
27.0
29.0
29.1
48.9
29.2
30.0
29.1
48.9
62.8
31.0
36.0
