Drawout Breaker - GE AK-1-15 Instructions Manual

Air Circuit Breakers Type AK-l-15 and AK-1-25 GEH-18"07
DRAWOUT BREAKER e
The drawout type circuit breaker (see Fig. 25)
consists of a circuit breaker mounted in a drawout
carriage. The drawout carriage is equipped with
guides, a racking handle and mechanism, and an
interlock arrangement which prevents'the insertion
or withdrawal of the breaker while in the closed
position. Also included are the primary and second-
ary dif)connect devices. This type of breaker is
used with weatherproof enclosures and switchgear
equipments such as "load center sub-stations. Their
use in the latter case is covered more completely in
Switchgear Instruction GEH-1830.
Inserting Breaker
'1'0
install the drawout breaker in the enclosing
case, proceed as follows:
1. Raise the breaker so that the guidef) (5) rest
in the supporting channel (4), Fig. 24.
2. Raise the rack-out handle and push the
carriage back until the 'rack-out pins on the
handle sockets rest against the back edge
of the housing rack-out cams (5), Fig. 24.
3. Push downward on the rack-out 'handle, thus
forcing the rack-out pins upward in the
housing cam and the primary disconnecting
devices into contact.
4. Pull the rack-out handle downward so that
locking pin (4), Fig. 25, is in the vertical
section of the cam slot (8), Fig. 25. The
breaker trip cam, guided by the rack-out
handle, now permits the breaker to be
closed.
Withdrawal
To withdraw the breaker from the enclosing
case, proceed as follows:
1.
Secondary Disconnect
2. Lever Interlock
3.
Rack-Out PiR
4.
Locking Pin
5. GUide
9
- ! ! - - - - 7
6. Hand! e Socket
7. Rack-OUt Handle
8. Cam Slot
9. Trip Cam
1. Trip the breaker by pushing the manual
trip button.
If
the breaker is not open the
positive interlock lever (2) will prevent
locking pin (4) from moving upward and
will thereby prevent withdrawal of the
breaker.
2. Lift the rack-out handle vertically. This
operation unlocks the breaker carriage and
raises the breaker trip cam, preventing
closing of the breaker.
3. Pull the rack-out handle forward in a cir-
cular motion until the primary disconnecting
devices are disengaged. The breaker can
now be removed from the enclosing case by
pulling foward on the rack-out handle.
NOTE: To test and inspect the drawoutbreaker
when it is not in the enclosing case, it is necessary
that the
lockin~
pin (4L, Fig. 25 be at the bottom of
the cam slot (8), Fig. 21>.
DISCONNECTS
PRIMARY DISCONNECTS
_ The primary disconnects (see Fig. 27) are
attached to the circuit breaker studs on the rear
side of the breaker.
Fig. 25 AK-I-25 DrawGut Breaker
Each disconnect consists of four contactfingers
(3) secured to each breaker stud (7) by screw (1)
and retainers (6 and 8). A pair of springs (2) exert
pressure on the contact fingers when engaging the
stationary studs (4). Stop
(5)
and retainers (6 and 8)
serve to maintain the proper alignment of the
fingers when engaging the breaker studs.
Fig. 27 illustrates the construction of the
primary disconnect for the AK-1-25 breaker. Note
that the eccentric bushing in the center of the
l1ssembly is positioned so that its thinnest wall
section is away from the breaker and toward the
stationary stud. The assembly of the disconnect
for the AK-1-15 is the same except the central
bushing is not eccentric and retainer (8) is of a
different design.
NOTE: For instructions on mounting the
breaker
by
means of disconnects, see "Dead Front
Breakers" under Installation.
27