Replacement; Adjustment; Auxil Iary Switch 2 - GE AKR-30 Series Maintenance Manual

SECTION 7-Breaker Maintenance (Cont.)
7.5.1 R EP LACEMENT
Figs. 2 2 , 23, 24, and 25 show the primary d isconnect
assem bly breakdown. Refer to these illustrations when
replacing the disconnects. Note the following details:
Fig. 25 - The position of the spacer i n the breaker stud.
The hole i n the spacer must be positioned as
shown so it will align with the holes in the clip.
Fig. 24 - The engagement of the fingers with the re­
tainer. Also the location of the 'bowtie' spacers i n
the fingers, both upper and lower.
Fig. 22 & 23 - The position of the u pper and lower
retainers and , agai n, the 'bowtie' spacers.
7.5.2

ADJUSTMENT

The primary disconnect assembly is factory adjusted to
apply a force of 85-1 05 pounds on a 1 /2 thick copper bar
i nserted between the upper and lower fingers. After i nstal­
lation of the disconnect assembly this force range is ob­
tained by tightening the locknuts to set the d i mension
shown i n Fig. 26 . 766" to . 797" Note that this d imension
is measured between the top of the retainer and the
underside of the washer. Also note that no bar is inserted
between the fingers when setting this d imension.
FIG. 26 - P RIMARY FINGE R ADJUSTMENT
7.6 AUXILIARY SWITCH
All electrically operated breakers and manual breakers
having shunt trips are supplied with auxi liary switches.
Depending upon the requi rements of the breaker's applica­
tion, the switch may contain from two to six stages. Usually,
each stage has one "A" contact and one " 8" contact. "A"
contacts are opened or closed as the breaker is opened or
closed. "8" contacts are the reverse of this.
The auxiliary switch is mounted on the upper side of the
mechan ism frame as shown in Fig . 27. A cran k on the main
shaft operates the switch through an adjustable link which
connects it to the switch crank. The switch can be a G E
type "S8- 1 2" or Electro Switch Type " 1 01 " .
22
FIG. 27 - AUXILIARY SWITCH LINKAG E

7.6.1 REPLACEMENT

Either switch type may be d ismounted by removing the
two bolt screws which fasten it to the mechanism frame.
The GE S8- 1 2 replacement switch should have its
cran k shaft set so that the arrow head on the end of the
sh aft poi nts as shown in Fig. 28A when the breaker is
open.
The Electro Switch replacement should have its crank
shaft set so that the horizontal line on the end of the shaft
is as shown in Fig. 288 when the b reaker is open.
FIG. 28A - GE SB- 1 2
CRANK SHAFT POSITION
If a switch is added to a breaker havi ng none, the ad­
j usting l ink wil l also have to be i nstalled. This is connected
to the pin on the crank which is attached to the main shaft.
It is secured by means of a cotter pin.
7.6.2 ADJUSTM ENT
GE SB- 1 2
I f a new adjustable link is installed, its length should be
set, before installing, at 6.375 inches, between pin centers.
After instal l i ng a new switch, its operation should be
checked. Viewing the switch from above, the contacts
toward the front of the breaker are normally the "8" con­
tacts. Even if a special switch is used, it is always the case
that the first two stages nearest the crank have the "8"
contacts to the front, and the "A" contacts towards the
back. "A" contacts are c losed when the breaker is closed.
"8" contacts are c losed when the breaker is open.
FIG. 288 - ELECTRO
SWITCH C RANK SHAFT