Advertisement
Figure 1: Operator panel controls of circuit breaker and manual charging of closing spring
54.0
53.0
Figure 2: Vacuum circuit breaker operator module
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
29.0
Moving-end connection pad
30.0
Vacuum interrupter
40.0
Moving-end pole head
48.0
Insulating coupler
49.0
Contact pressure spring
60.0
Mechanism housing
8
Vacuum interrupter/
operator
59.0
58.0
55.0
Item
50.5
50.5
53.0
54.0
55.0
58.0
59.0
27.0
28.0
20.0
30.0
16.1
16.0
16.0
Introduction
The type 3AH35-SE vacuum circuit-breaker
operator is intended for stationary
applications, such as the type SDV7-SE
outdoor distribution circuit breaker. The type
3AH35-SE circuit breaker conforms to the
requirements of ANSI/IEEE standards,
including C37.04, C37.06, C37.09 and
C37.010.
The circuit breaker includes three vacuum
interrupters, a stored-energy operating
mechanism, necessary electrical controls and
an operator housing. In a typical installation,
insulating barriers may be located between
Description
the vacuum interrupters.
Manual spring
This section describes the operation of each
charging port
major subassembly as an aid in the operation,
Close pushbutton
maintenance and repair of the circuit breaker.
Open pushbutton
Vacuum interrupters
CHARGED/
The operating principle of the vacuum
DISCHARGED
interrupter is simple. Figure 3: Vacuum
indicator
interrupter cutaway view on page 9 is a
CLOSE/OPEN
section view of a typical vacuum interrupter.
indicator
The entire assembly is sealed after a vacuum
Operations counter
is established. The vacuum interrupter
stationary contact is connected to the fixed-
end pole head of the circuit breaker. The
vacuum interrupter movable contact is
29.0
connected to the flexible shunt associated
with the other pole head and to the driving
40.0
mechanism of the circuit breaker. The metal
bellows provide a secure seal around the
movable contact, preventing loss of vacuum
16.1
while permitting motion of the movable
48.0
contact along the axis of the vacuum
interrupter.
49.0
When the two contacts separate, an arc is
initiated that continues conduction up to the
following current zero. At current zero, the
arc extinguishes and any conductive metal
vapor that has been created by and supported
60.0
the arc condenses on the contacts and on the
surrounding arc shield.
Contact materials and configuration are
optimized to achieve arc motion and to
minimize switching disturbances.
Advertisement
