GE AKR-30 Series Maintenance Manual page 116

SECTION 8-Contact Maintenance (Cont.)
8.3 C ON TACT A D J U STM ENT ­
AKR30L, A K R50/50H & A K R U 50
The contact breaker shown i n F i g . 47 is used by
AKR30L and all AKR50 b reaker types. This structure
uses two movable contact arms. Each arm acts
against a stationary arc i n g , a stationary i ntermed iate
and th ree stationary mains.
The following p roce d u re is used to perform the wipe
adj u stment.
1 . Open the breaker, remove arc q uenchers.
2. Arrange the b reaker for slow-closing.
3 . Select one pole of the b reaker and p lace a t h i n
sheet or stri p of to u g h insu lating material , such as
mylar, over the stationary arcing and i ntermed iate
contacts. Th is stri p s h o u l d be about two i nches wid e
and m ust p revent the arcing and intermed iate contacts
from making contact when the b reaker is cl osed .
4 . U sing the ratchet i n g mai ntenance handle, slow­
close the b reaker with the i ns u lation held in p lace.
Examine the insu lation to m ake s u re it "over-hangs"
below the i ntermed iate contacts, but not enough to
cover the main contacts.
36
FIG . 47 - 1 600 A M P CONTACT STR UCTU RE
5. Attach a continuity checker (bell-set, light, or ohm­
meter) between the upper and lower stud. The checker
should indicate continuity exists.
6. Facing the breaker, turn the wipe adjustment stud
shown in Fig. 47 clockwise unti l the checker indicates that
the main contacts are separated.
7. Turn the stud counter-clockwise unt i l the main con­
tacts j ust touch.
8. From this point, advance the stud counter-clockwise
270 degrees. This wi ll be 4-1 /2 flats.
9. Once the adjustment is complete, verify that the torque
required to j ust turn the adjustment nut is greater than 40
in-lbs. I f less torque is requ i red, carefu lly add LOCTITE 220
or 290 to the adjustment nut threads. Wipe off any excess
LOCTITE. Once the LOCTITE is set, recheck the torque
valve.
10. Trip the br�ker, remove the i nsulating strips.
1 1 . Repeat the above procedure on the other two poles.