Inspection; Lubrication; Separation Of Front And Back Frames; Maintenance 5 - GE AK-2A-15 User Maintenance Manual

INSPECTION

B E F ORE INSPECTION OR ANY MAINTE­
NANCE W ORK IS D ONE, BE SURE T HAT T HE
BREAKER IS IN T HE OPEN P OSITION.
E LECTRICAL P OWER, B OT H PRIMARY A ND
C ONTROL S OURCES, S HOU LD A LS O BE DIS­
C ONNECTED.
Periodic inspection of the circuit breaker
is recommended at least once a year.
frequent inspections are recommended, if severe
load conditions, dust,
favorable conditions exist.
If the breaker remains open or closed for
a long period of time, it is recommended that
arrangements be made to open and close it several
times in succession,
At all times it is important not to permit pencil
lines, paint, oil or other foreign materials to re­
m ain on the insulating surfaces of the breaker
as they ma y cause low resistance between points
of different potential and result in eventual elec­
trical breakdown.
Always inspect the breaker after a short
circuit current has been interrupted.
At the time of periodic inspection, the follow­
ing checks should be made after the breaker has
been de -energized.
1 . Manuall y operate the breaker several times
checking for obstructions or excessive friction.
2 . Electrically operate the breaker several times
(if breaker has electrical control) to ascertain
whether the electrical attachments are func­
tioning properly.
3 . Remove and inspect the arc quencher. Break­
age of parts or extensive burning will indicate
ne ed for r eplac ement.
4.
Check contact condition and wip e
5 . Check latch engagement.
6. Check operation of tripping devices, including
overcurrent trip devices, making sure all
have positive tripping action.
movement in tripping direction beyond point
of tripping. )
(For detailed information o n breaker features
listed, refer to appropriate sections of these
instructions .)

SEPARATION OF FRONT AND BACK FRAMES

Figure 3
Man y maintenance operations will either re­
quire or be greatly facilitated by separating the
MAINTENANCE
moisture, or other un­
preferably under load.
(Discernible
front frame and mechanism of the breaker from
the back frame or base, which consists of the
current carr ying parts of the breaker and their
supporting struc ture.
operation is as follows :
ALL
1 . Remove the arc quenchers (see section on
"Arc Quenchers ").
2. Disconnect the two insulated connecting links
(6), between the mechanism and the crossbar
More
( 10), by removing the tie bolt (7), and slipping
the ends of the links off the ends of the should­
ered pin, {5) Figure 5 in the mechanism.
3 . If the breaker is a drawout type, with secondary
disconnects, Figure 2, remove the secondary
disconnect supporting bracket from the breaker
back frame.
retainers that may be attached to the back
frame.
4. Remove one elastic stop nut from each of
two s tuds (3), which tie the upper ends of the
mechanism frame to the back frame of the
breaker.
5. Remove the two elastic stop nuts {9/1 6 " Hex.)
which fasten the wrap around portion of the
front frame to the back frame. One of these
is located on each side of the breaker, about
2/3 of the distance down from the top edge
of the back frame.
On drawout breakers for AKD Equipment, the
bottom plate must be removed by first remov­
ing two # 8 -3 6 screws located at the front of the
bottom plate and then freeing the plate from the
slots located in the bottom of the back frame.
6 . The two frames are now disconnected. How­
ever, care should be exercised in separating
them to avoid dam age to the trip shaft arms
and paddl es.
steady, lift the front frame and mechanism
up and out so that the trip paddles on the
trip shaft clear the trip arms of the overload
trip devices .
Reassembl y of the two breaker halves is
accomplished b y following the procedure out­
lined in reverse order.
In general,. the circuit breaker requires very
little lubrication.
surfaces should be lubricated very lightl y at the
regular inspection periods with a thin film of
extreme temperature, high pressure, light grease,
similar to G. E . Spect. No. D50H1 5 or RPM No. 5.
Hardened grease and dirt should be removed from
latch and bearing surfaces by the use of a s afe
cleaning solvent such as kerosene. Latch surfaces
should be left clean and dry and not be lubricated.
The p rocedure for this
Also remove any wiring bundle
While the back frame i s held

LUBRICATION

Bearing points and sliding
5