GE AK-1-15 Instructions Manual page 10

GEH-1807 Air Circuit Breakers
Type
AK-l-15and AK-1-25
ADJUSTING CONTACT WIPE
AND
CONTACT
PRESSURE, FIG. 6
1. Remove arc quenchers (see "Replacements"
under Arc Quencher).
2. Remove tru-arc retaining ring from main
shaft (16), Fig. ;3, nearest the insulating
link and contact assembly
to
be adjusted.
3. Loosen clamp (9) which secures eccentric
bushing (8).
4. Turn .the eccentric bushing in the insulating
link (7) threby moving the insulating link
closer or farther away from the stationary
contacts, as required to obtain proper Wipe.
5. Re assemble parts in the reverse order
after making adjustments.
NOTE: To adjust the insulating link in the
center pole unit, first, push the main shaft through
the right hand insulating link and into the. center
link as described in item 2 and 3 above. Opening
spring and cap will drop out. Adjust center in-
sulating link as described in item 4 above. Re-
assemble parts in reverse order being careful to
replace opening spring and cap in their proper
position.
If any of the contacts are badly corroded or
pitted, thereby making it impossible to adjust for
proper contact pressure or contact wipe, such
stationary contacts or movable contact assemblies
should be replaced. See "Replacements" below.
If the proper contact pressure does not exist
when the wipe is within its limits, the stationary
contact springs must be replaced.
REPLACEMENTS
Movable Contact Assembly, Fig. 6
1. Remove arc quenchers (see "Replacement"
under "Arc Quencher").
2. Remove main shaft from breaker by re-
moving tru-arc retainer from one end and
pushing shaft through insulating links (7).
As shaft clears the mechanism side frames
the opening springs and caps, (17) and
(18)
Fig. 3, will probably drop out of their re-
cesses in the Side frames.
If
breaker is of
the drawout type, handle socket, interlock
lever, bushing and nut must be removed on
side from which the main shaft is to be
removed. (See Figs. 4 and 5.)
3. Remove upper mechanism mounting screws
(refer to Fig. 4).
4. Loosen lower mechanism mounting screws
by using screw driver in slot provided on
threaded end of screw which projects through
back frame of breaker. (See Fig. 7.)
5. Mechanism and attached components may
now be lifted clear of the breaker. If
breaker is of the drawout type, movement
of the mechanism will be somewhat re-
stricted by control wires. There will be
enough freedom, however,
to
allow the mech-
anism to be lifted to the top of the drawout
fram~
where it can be secured by tying.
(See .1''ig. 8.)
10
6. Remove insulating link (7) by removing
tru-arc and drifting out pin (11).
7. Remove clamps (14) by removing fastening
hardware.
8. Remove series coil terminal bolts. Movable
contact unit is now free and may be removed.
9. Breaker may now be reassembled with new
contact assembly
by
reversing the above
described procedure.
In
remounting mech-
anism, be sure that dowels
ir.
mechanism
side frames are well seated in dowel holes
in the pole unit base. (See Fig. 8.)
It
will
also· be necessary to COmpress the opening
spring and cap in the recess in the mech-
ariism side frame in order to obtain clear-
ance for replacement of the main shaft.
10. Check contact wipe and pressure and adjust
if necessary.
FI
g.
Il Arc Quenc:hen and Handle Socket
Removed fro. Drawout Breaker
Fig.
5 Removal of Main Shaft
f~
Drawout Breaker
t>
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