Manual Maintenance; Closing Of Electrical Breakers; Electrical Closing; Quick Close For Electrical Breakers - GE AK-2-50 Maintenance Manual

GE;K-730~ Low Voltage Power Circuit Breakers
MANUAL MAINTENANCE
- .
~
CLOSING OF ELECTRICAL
BREAKE~S
· An electrical breaker may be closed manually
by _ means of the maintenance handle furnished
'with the breaker. ·
· To observe ~e operation of the breaker with- ·
out power, with the break~r open and springs
discharged, proceed as follows:
1. · Charge the · closing spring with tbe main~
te~ance han~e
(1,
Fig. 3) until the indica-
tor rea~ "charged": .
2. Continue to
operate the.maintenance handle
until the breaker close~.
3. Open. ·the breaker by . pushing· the trip .
· _· button (4,
"F~1t.
2)~ . . .
ELlCl'.RICAL CLOSIN~
The - electrical c ontrol s·ystem ·is comprised
of- an- X relay, two double _contact mechanically
operated switches (F anq G), a push outton closing
switch and _ a ny means for remote closing which
the user may incorporate into the system. When
voltage is . .first. applied to the breaker, (before any
closing s'ignal is given) the motor is energized
through two of the X relay contacts and the two
a·.
switch contacts. · The - .motor then compresses
the closing springs to the "pre-charged" position
at which point the mechanically operated F and G
· switc~es are ope_ r ated. This ope_ n s the G contacts,
stop~mg the motor, and closes the F contacts, whicp
readies the system for the. actual closing of the
breaker. . When the push button ~r remote switch ·
signals ·for a closing operation, the X relay coil is
e~ergized, operating the X contacts. This seals
· in the X relay and energizes the .motor once again
and tl?,e closing operation takes place. . .
QUt:CK CLOS.E
FOR ELECTRICAL BREAKERS
. Functionally, the ·quick close mechanism differs
from the standard electrical mecbanism in that the
pre-charge operation is extended · to completely
charge the closing springs. At the end of the charg-
ing oper~tion, w~ch takes approximately 5 seconds,
a latch plate engages the prop roller to prevent
_ the closing springs from discharging. .
. With the closing springs fully charged the
breaker is ready for a closing operation upon
release of the prop roller. This may be accom-
plished either m~ually, by depressi. n g the closing
.lever on. the breaker, or electrically by closing
the remote closing switch. Upon the release of
. the prop roller the closing springs discharge and
close the breaker in the same manner as on the
· stan~ard electrical breaker.
· Wi~. control voltage appli~d, :the motor is ·.·
energized through the . G switch . contacts, · and
charges the closing springs. When the springs
4
reach the fully charged position; the mechanically
operated switches operate, reversing their coniact:S.
Upon operation of these switches the motor. 1s
stopped by the. opening of the G swit~h. The closing
of the F switch prepares the bre.aker for- a
closing operation.
Fig. 2 (8939671)- Front view of AK-2-50 bre~e~
.
1. Auxiliary Switch · .
2. Position Indicator
3. Relay
4. Manual Trip Button
5. Shaft for Manual Mainte- ·
nance Closing Handle · ·
6. Spring Charged-Discharged
Indicator · ·
7. Motor Cut-off ·Switches
8. Arc Quenchers
A closing signal now given ·energizes the cont;;
relay X whose contacts close and comple: the
circuit through the closing relay coil.. Wi
8
closing relay coil energized the breaker clo~e g
.as descr~bed above. At the same time the· clos:P
l\elay contact closes to energize the anti-pU
rel~y .causing its c· o ntacts to re\_'erse providing
the .anti-pump feature. ·
When the breaker closes, the mechanical oper~~
ted G switches close to energize the motor ag~-
. and the F switches open and de-ene:1;gize the :er-·
trol relay from being .energized until the brtsed
is tripped open. With' the . G switc~es c dy'
the motor charges the closing sprlngs rea
for the next closing operation.