Siemens-Allis FC-10008, Instructions Manual

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Tl L Tl NG ARC CHUTES
Remove phase barriers as described under "Phase
Barriers Assembly" (refer to Figure 10).
Remove screw (16) of the blowout coil, screw (7) of
the front arc runner and front screw
(6)
onhe arc chute of
each phase (see Figure 2).
Position arc chute support at the rear of the breaker
and tilt back the arc chutes as shown in Figure 2A.
After arc chutes are tilted back to their normal posi·
tion, make sure all screws are tightened securely on all
phases before phase barriers are replaced,
NOTE
Make sure that blowout coil s are reconnected
with front screw
(71
and rear screw (16) (Figure
2).
BA RRI E R STACKS
'lbe barrier stacks (3, Figures 2A and 6) are fragile
and must be handled carefully. Inspect the barrier stacks
(3) for erosion of the plates in the areas of the slots. The
barrier stacks (3) should
be replaced when a milky glaze
appears on the full length of the edges of most of the slots.
They should also be replaced if plates are broken or cracked.
When cleaning the breaker and cubicle, inspect for pieces
oC barrier stack refractory material which would obviously
indicate breakage.
To remove the barrier stack (3), tilt back the arc
chutes one at a time as in Figure 2A. remove screws (13)
(see Figure 6), coolers (6), screws (12), dividers (11) and
slide barrier stack ( 3) through the top of the arc chute. When
replacing barrier stack (3), lay the "shoe-hom" guide
(2, Figure 2A) in position on the bottom endplate of the
tilted
arc
chute to avoid upsetting and destroying the end·
plate seal that could result in difficult Insertion of the
barrier stack and breakage
of its plates. Slide in the barrier
stack (3) making sure V-shaped slots go In first. Install
coolers
(6) with screws (13) and dividers (11) with screws
(12). Tilt the arc chute back to its upright position and
pull out "shoe horn" guide (2, Figure 2A) from the top of
the arc chute.
TRANSFER STACK
Transfer stack (34) shown in Figure llC are as fragile
as the barrier stacks and likewise, should be handled
care­
fully. Transfer stacks (34) should be replaced if milky glaze
appears on the edges
of
the slots or
if
plates are broken or
cracked. To remove the transfer stack (34), remove one
of the two sideplate supports (33). Hold the transfer stack
·17-
(34) with one hand to prevent it from falling down while
the sideplate support ( 33) is being taken out. To install the
transfer stack (34), follow the reverse order of above.
CONTACT ALIGNMENT AND REPLACEMENT
The main and arcing contacts are an Integral part of
bushing assemblies and are carefully aligned with upper and
lower bushings before shipment. Nonnally, no further ad·
justment Is necessary.
The procedures which follow are to be used if it
becomes necessary to change contacts, adjust penetration,
or restore contact alignment (refer to Figures
llA,
118 and
llC).
PRO CEDURE A Contact Alignment and Pe netration
(Stroke
I
1. The check for proper contact alignment and pene·
tration
can
be made at the same time by measuring dlmen·
tions
"C",
view "A·A", Figure 11A.
2. Using power closing procedures, close and latch
breaker. The main contacts will have spread apart leaving
gaps between the stationary main fingers (8, Figure llA)
and plates (7). Penetration is detennined by measuring
these gaps, dimensions
"C",
with feeler gages.
3. Alignment and penetration are satisfactory if the
sum of left and right hand
"C"
dimensions total 0.090 to
0.120 inches (2.29-3'.05 mm). The minimum
"C"
dimen·
sion on either side is 0.040 inches (1.02 mm).
4. If either a left or right hand
"C"
dimension is less
than 0.040 (1.02 mm) contact alignment will require ad­
justment. This adjustment is made by opening the breaker,
scribing the position of blocks (8 and 13, Figure
llC).
loosening screws (24 and 25) and moving blocks (8 and 13)
sideways to equalize the dimensions "C" between each side.
The scribed lines serve as a reference. Refasten screws (24
and 25 ).
Close breaker and check alignment. When
. making this adjustment be sure block
(8)
is firmly seated
against ridge on top of stud.
5. If the total of
"C"
dimensions
are
less than 0.090
inches (2.29 mm) penetration will require adjustment. This
adjustment is made by lengthening or shortening link (47,
Figure llA). Adjust length of link (47) by removing or
inserting washers between the base of
"T" casting (9) and
checkout (10). Use a 0. 6 2
5
ID by 1.25 00 by 0.03 thick
(15.9 10 by 31.800 by 0.8
mm
thick) brass washer, Siemens·
Allis part number 71-018-451·001. Adding washers will
increase penetration,
"C"
dimensions will increase. The
adjustment should proceed by adding or removing a single
washer at a time.
Make sure this adjustment brings
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