Westinghouse RC, Инструкция по эксплуатации

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I N ST A L L ATI O N
•
Westinghouse
L L. 4 1 -661 E
O PE R A T I O N
•
MAINTENANCE
I N S T R U C T I O N S
TYPE RC AUTOMATIC RECLOSING RELAY
C A U T I O N Before
putting relays into service, remove
a l l
blocking
w hi c h
may have been inserted for the
purpose of
s
e
c
urin
g the parts during shipment, make
sure that all movini!" parts operate freely , i n spect the
c o ntac ts
to
see that they are c lean anrl c lo se prop­
erly , and operate the re l ay to c he c k
the settings and
e l e ctrical c
onnec
tio
ns.
A P P L I C A T I O N
The type RC autom atic reclosing relay is used
for automatic reclos ure
of AC
o r
DC
e l ectri cally oper­
a ted c ircuit breakers after they have been opened by
o v er c urre nt o r o th er p rotective re lay acti o n . The relay
may
be adjusted to provide s e v eral rec losures
at pre­
d etermin ed
time
i ntervals ,
so
that in c as e the breaker
does not remain c lo s e d after the first rec l osure addi­
tional rec l o sures w i l l b e mad e . The first rec lo sure
u s u a l ly is an instantaneous re c losure thro u gh pre­
c lo s ed contacts s in c e system operatin g e xperience
has s hown that the maj ority of faults are of a tem­
porary nature , such as l i ghtni n g flashovers , and w i l l
n ot be re-establi s hed after i nterruption of t h e fault
c urren t. Consequ ently , serv i c e i nterru pti o n c an be
minimized by the use o f a n i n s tantaneous rec losure .
How ever, the first rec lo sure may be de lay e d if rie s i red.
In c as P thP c ir c uit break e r does not remain c lo sed
after the first rec losure , the rPlay wi l l make additional
rec losurPs at s ui t a bly grade d interval s . It is commo n
p mctice
t o m a k e t w o addit i o n a l rP c losure s . but the
relay may he ad ju sted to m ak e any number up to a
total of s i x reclo sures i f desire d . If the breaker does
not remai n c losed aftPr the final rec losure , the ti m i n g
drum stops i n
th • ·
" Lo c k out" p o s i t i o n , a n d any further
attempts at rec
Ill sure must b e m ad e by manual o pPra­
tion of the c o ntrol s w i tc h . H o w P V P r , if the hrP aker
remai ns c lo s e d atler any autom at i c rec losure , or, s u b­
sequently , after manual rec losure , the relay ti ming
rirum will arivance to and stop at the "Start" positio n ,
wh PrP t h e rP la.v i s i n read i n P s s for another cycle o f
automa t i c rPc los un's
follo wi n g
t h P n e x t tri p p i n g o f
t h e hre a k<'f.
For a ny automati c rPdn s i n g appli catio n , the de­
ratin g factors for tm'akPr i n t Prru p t i n g abilitY s hould
SUP ERSEDES I . L. 41 -66 1 0
* Denotes ch ange from s uperseded i ssue.
be checked when c hoosing any particular reclosing
cycle. Also, when using instantaneous first reclosure
it is necessary that the protective relays open their
contacts w ithin 10 cycles or less after the breaker
is tripped in order that the trip circuit will be de­
energized before reclosure takes plac e .
CO N S T R U C T I O N
As shown in figure l , the RC relay consists of a
latching solenoid unit, Y , a synchronous motor driven
timing unit and an instantaneous auxiliary unit, X.
An additional instantaneous unit,
Z, is also provided
when s pecified.
T i m i n g U n i t
The tim ing unit contains a synchronous motor and
gear t
r
a
i n mounted
behirul. the front sub-base. The
gear train drives a drum with c ams, which actuate
c ontacts
1 , 2 , 3 , 4
and
1 4 . Cam 5 actuates the Y unit
latch to reset the
Y unit and c lose the Y 1 3 contact.
Cams # 1 a nd tt 2, w hich o perate contacts 1 and 2
re
s
pec
t
i
v
e ly
,
are
notched and are not intended to be
adjusted
i n the
field. Cam #3 is a s eries of flat
s
pri ng
s
s e c ured by
scre w s , which c an be located at
any poi nt on the periphery
of the drum. Cams #4 and
#5 consist of s c re ws which c an be set at any point on
th e periph ery of the drum . Cam #14 is a s i n
gl
e micarta
b l o c k , l o c ated to the rear o f the cam #5 position and
held by a #5 cam s c re w .
The g e ar tra i n rPdu
ct
i
on ratio i s adjustable. The
dm m s p e e d dial c o n tai n s i n d i c e s , w hi c h are l i ne d
up
w ith an index mark to m esh the proper gears for the
rie s ir e d drum s p e e d . A clamping s crew is provided at
the edge of th
is dial . A push rod is located on the
front of the
drum to demesh the drum and permit free
manual drum rotatio n .
T h e d i a l o n t h e
timing drum has 60
divisions
( s P c on d i ntervals with
60 s
e
co
nd drum speed). The
P dges of the #3 , 4 and
5
c am s lots h ave
1 2
equall y
spac Pd w hite marks corre s p o nd i n g
to 5 s
e
con
d in­
tervals with a 60 second drum speed.
EF FECTI VE MAY 1 967
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