Mechanism - GE AK-2A-15 User Maintenance Manual

(15) on the center pole into position.
ment pin
Be sure the stationary insulation barriers
are correctly located.
4. A lign the cross bar with the left and right
pole pivot supports and install the left and
right pole movable contacts.
nosed steel pin to aid in aligning the holes
in the cross bar, the contacts and the pivot
supports.
5.
Install the left and right pole pivot pins while
threading them through the spring c lips and lock
(9).
the spring c lips
are fully inserted.
6. Adjust the contact wipe to
adjusting the eccentric contact wipe adjusting
(15).
pin The breaker must be open to adjust
the wipe. In the event acceptable wipe cannot
be obtained by moving the contact wipe ad­
(15), from the movable contact
justing pin
forward or backward as necessary to bring
the wipe within the range of the contact wipe
(15). Do not exceed the recom­
adjusting pin
mended settings for wipe;
breaker may not c lose comp lete ly .
viewed from the top with the breaker c losed,
the m�vable contact should be centrally located
with respect to the stationary contacts.
the movable contacts are not centrally located
as shown in section CC, form the movable
contacts until they are nom inally �entered.
If the moving contacts are not centered with
1/8" separation when closed against the fixed
contacts, they shou ld be bent laterally (after
opening the breaker contacts) .
without squeezing the two movable contact
arms together, a
inserted between them;
grasped with p liers and bent in the desired
direction for centering.
New contacts should be adjustable using
eccentric numbers 1, 2, or
are the ones visible when viewing the breaker
from the front, not from above . (The higher
numbers should be reserved for tightening
at future maintenance readjustments after
if
wear . ) Also,
where adequate wipe is obtainable at settings
1, 2, or 3, it is possible that the stationary
contacts will bottom, producing excessive back
force on the breaker c losing mechanism so that
the toggle link will not pass center.
result, the breaker wi ll not complete its stroke,
and inadequate pressure and wipe will result;
burn-up of contacts from just load current
will follow.
If the required wipe of new contacts c annot be
obtained with eccentric number of
bending of the contact arms toward the closed
position is required.
individually, using an
tapered open end wrench to grasp the contact
10" C rescent or the 1" - 1-1/8" tapered
and a
Use the bullet
Be sure the pivot pins
1/8" 1/32" by
.:!:.
otherwise the
To do this
1/8" spacer p late should be
then the pair c an be
3.
These numbers
higher numbers are used,
3 or lower,
This should be done
8" C rescent or 1/2 - 5/8"
Power Cir cuit Bre akers Types AK-2-15 and AK-2/3-25 GEI-50299
1
2
3
4
When
If
(8039851) AK-2-25 Back F rame - Loca­
Figure 4 .
tion of C rossbar and Po le Shields
1.
Stationary Contacts
2.
Movab le Contacts
3.
Upper Stud Asbestos Shield
4 . Crossbar Plastic End Shield
5.
Crossbar Assem'bly
6 . C rossbar As bestos Inner Shield
7 . Lower Stud Asbestos Shie ld
open-end wrench to grasp the pivot portion of
the arm.
little difficulty.
identically.
As a
Operate breaker several times, and recheck
wipe to make sure bending of movable arms
did not occur in these operations.
7. Operate the bre aker manually several times
to assure proper functioning occurs, then
rep lace the U shaped insulation
and arc quenchers.
quenchers be sure the quencher is seated
downward completely and that the quencher
clamp covers the knobs protruding through
the arc quencher insulation.
The soft copper arm will bend with
Both arms shou ld be bent
When rep lacing the arc
(5) Figure 3
11