Operation
De
sc
ri
p
ti
o
n
The continuous current and interrupting ratings of the circuit
breakers are as shown on the circuit breaker rating labeL
The circuit breakers are also available with integrally mounted
current limiting fuses through
2000A
frame size, and with
separately mounted fuses for
3200A
and
4000A
frame size.
For
800A, 1 600A.
and
2000A
frame sizes the basic circuit
breakers are the same with or without fuses. The fuses mount
on a bracket that is bolted to the side plates and upper studs
on the back of the circuit breaker. Due to this difference. fused
circuit breakers are not interchangeable with unfused circuit
breakers. The current limiting fuses i ncrease the interruption
rating to that of the fuses. Fused circuit breakers are identified
as
RLF-800, RLF-1600, RLF-2000. RLF-3200,
or
RLF-4000.
Fused circuit breakers are also equipped with an open fuse
trip device to open the circuit breaker if one or more current
limiting fuses open.
Note:
Fused circuit breakers are not physically interchange
able with unfused breakers.
Unfused circuit breakers can also be supplied for stationary
mounting in which the rackin g components are omitted and
brackets are provided for mounting to a stationary frame.
A l l
RL
c i rcuit b reakers u s e the same basic c l o s i n g
mechanism o r operator. The closing springs used vary be
tween sizes.
Two configurations of the operator are available for charging
the clos i n g s prings, manually charged or electrically
charged. F
o
r electrical operators. a maintenance handle
accessory can be used to charge the springs manually for
maintenance or i n an emergency. Optionally, a built-in
manual spring charging handle can be provided.
The manual and electrical operators are identical except for
the means of supplying energy to the closing springs. A
double-togg le, trip-free mechanism is used. This means that
the breaker contacts are free to o pen at any time if required.
regardless of the position of the mechanism.
Precautions to
be
Observed
in
Operation
1 .
Read
this
Instruction
Guide before i
ns
t
a
l
l
i
n
g or
making
any changes or adjustments on the circuit breaker.
2. Stored-energy closing springs may be charged with cir
cuit breaker contacts in either the open or closed posi
tion. Extreme care should be taken to discharge the
springs before working on the circuit breaker.
3.
When closing manually operated breakers out of the com
partment. the racking mechanism must be returned to the
test position before the closing spring can be charged.
4.
vVhen charging manually operated breakers. always hold
the handle firmly until it is returned to the normal vertical
position. A ratchet insures that the closing stroke must be
completed once started.
5. Check current ratings. circuit breaker wiring information,
circuit breaker type and trip device type, against the
One-Line Diagram to assure that circuit breakers are
l ocated i n t h e p ro p e r c o m p a rtments w i t h i n the
sv:itchgear.
6.
Check the alignment of the secondary
disconnect
fingers.
6
This
ensures against misalig nment due to possible distor
tio:� of finger
s
du ring
the
s
hipme
n
t an
d
ha
n
d
li
n g
.
7. Close the compartment door and secure door latch(s)
prior to racking the circuit breaker to or from the CON
NECTED position. Also close and latch the door prior to
closing the circuit breaker when i n the CONNECTED
position. Once the circuit breaker is closed, keep the door
closed.
8.
Once the circuit breaker is energized, it should not be
touched, except for the exterior controls.
Manually Operated Breakers
The breaker has a center-mounted frame so many of the
latches and links are arranged in pairs. For descriptive pur
poses. they will be referred to as single items.
Refer
to
Figure
2
and
Table 1 .
Detail (A) shows the position of the trip
latch and toggle linkage when the circuit breaker is open and
the closing springs are discharged.
Table 1 .
Operatin g Procedure Manually Operated Circuit Breakers
Operation
Charging
Springs
Closing
Tripping
Procedure
Pull charging handle down all the
way (approximately
1 20•)
and return
it to normal vertical position.
(Engagement of pawl with ratchet
teeth prevents handle reversal until
the downward stroke is completed.)
Push down firmly on spring-release
latch hood
(50)
after handle is
returned to normal vertical position.
Push in manual trip rod
(94).
OR
If
shunt trip is provided, operate
remote trip control switch (CST). (See
Figure
3.)
Movement of the charging handle downward rotates closing
ratchet
( 1 40)
against roller
(43).
thus pivotin g dosing cam
(34)
clockwise about pin
(40).
This extends the closing
springs through link (4 1 ) and spring hanger (58). Rotation of
cam
(34)
allows roller (27) in toggle linkage to be moved into
position shown in Detail
(B).
Kickoff spring ( 1 0) moves rollers
away from the sh?P block (7). Then the toggle linkage is
moved by torsion spring until latch ( 1 5) clears trip flap (1 2).
Spring
( 1 3)
causes trip flap
( 1 2)
to reset u nder l atch ( 1 5). Trip
flap
(
1 2)
should normally stop against the front surface of
latch ( 1 5).
When the closing springs are fully charged, roller
( 43)
engages latch (47). Closing ratchet
( 1 40)
engages a pawl
in
such a manner that the charging cam must complete the
charging stroke before it can return to its normal position.
With the charging handle in its normal upright position. the
circuit breaker can be closed. By pressing firmly on hood
(50). latch ( 47) will disengage roller
(
43).
Then closing springs
cause closing cam
(34)
to rotate against the toggie rollers
(27). moving the toggle into
its
upright p
o
si
t
i
o
n
,
as shown in
detail (C). The cl
o
si
n
g cycle can be i nterr
u
pte
d
at
any point
by
opera:ion
of one
of
the tripping means. This will cause
rotation
of
trip flao ( 1 2)
to
a
positio:�
that releases la:ch 1 1 5; .
allov
'.
ing. togg ie linkage t o collapse t o :he position
shown i:�
de:a11
<A;.
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