Westinghouse RC, Инструкция по эксплуатации

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TYP E RC AUTOMATI C RECLOSING R ELAY
R C S e tt i n g s
I n t he RC relay per internal s c he m atic 1 8 8 A1 84
(figure 1 1 ) t he co nne ction betw e e n co ntact 113 an d the
anti-pump c irc uit has be e n s e parated s o that e xternal
devic e s c a n be c onnected betw e e n t erminals 1 6 and
1 8 , as shown in figure 9 . Some of the factory c am
settings for the RC relay must be c ha nged to pr ovide
tim ing as s how n in figure 1 0 . The cam s pr in g w hich
precloses the 113 c o ntact in t he start pos ition s h ould
be r emoved ::>o that insta nta ne ous rec los i ng may b e
i nitiated b y the SX a nd 11 1 4 c o ntacts. T h e t hird
re clos ure must be ad vanc e d t o the 40 s e c ond p oint
or earlier by mov ing the a s s oc iated 11 3 cam spr ing ;
t he assoc iated 11 5 c am screw mus t be relocated to
reset Y at 45 s e c onds . Als o , a cam s pring mus t b e
added to c ause 11 3 c ontact closur e at 5 0 s e c onds ( or
e ar lier) for recl osure under synchro-verifie r c ontrol
at intermediate lock out , a nd a 11 5 cam screw mus t be
added t o r e s e t Y be fore the final loc kout or s tart
pos itions are reac hed after the final rec losure .
A 11 4 c a m s crew must b e added t o provide a
c losure at app roximately 4 8 s e c ond s , just prior to the
intermediate lockout positi o n . In this s cheme the #4
c ontact functions not only to actuate the final lock­
out alarm but also to control interm ediate lockout and
the following reclosure , via auxiliary relays 79-4X
and 7 9 -4 Y, upon restoration of line voltage after a
p e rm anent fau lt . If intermediate lockout is d e s ired at
a time less than 50 se conds from the start of the
reclosing s equence , the cams which actuate the #3
an d #4 contacts may be moved to c lose sooner than
the 50 and 48 s ec ond points shown in figure 1 0 .
Approximately 1 0 s e c onds mus t s ep arate reclosures
to insure that the Y unit has sufficient time to be
res e t by the #5 c am . Thu s , to advance the inter­
mediate lockout time , it is necessary to advance the
third reclosure by at le ast the s ame amount.
I n s imilar fashion , inte rmed iate lockout must
occur at least 1 0 seconds prior to the start pos ition
::>0
that final synchro-ch eck reclosure will not l e ave
the Y unit in the latched pos ition . A # 5 c am s c rew
must be added to reset the Y unit as already men­
tioned and must clear the latch arm before the drum
reaches the final lockout position.
The other factory c am s e ttin gs are satis fac tory.
In c ertain styles of the RC relay , c am s e tting c han ges
s imilar to those just d e s c ribed may alre ady have been
m ad e .
I n s t a n t a n e o u s R e cla s e
Assume a high s p e e d trip for a line fau lt. This
energizes the SX ope rating c oil which is in s eries
with the trip coil 5 2 T . The SX contac t along with
the closed Y 1 3 an d 14 contacts ess entially bypass
the #3 c ontact reclosing circ uit to initiate immediate
reclosin g . At the same time the X-Y anti-pump c ircuit
is energized in the c onventional manne r , picking up
the Y unit, o pening the Y 5 contac t to pr e vent m ore
than one rec losing impuls e . I n addition , the ope ration
of the anti -pump circuit results in the opening of the
Y 1 3 c ontact. By the tim e th e Y 1 3 opens the breaker
close c ircuit s hou ld b e s ealed by a 52X contact or
equivalent. If the c lo s e c ircuit does not have a s e al
around Y 1 3 and 1 4 initi ating c on t ac t , an internal
jumper s hould be added around the Y 1 3 c ontact to
prevent prem ature de-ene rgization of t he bre aker
close circuit. Whether Y 1 3 is jumpe re d or not, th e
instantaneous r e c los e c ircuit is o pened s oon after
the drum moves off the s tart position s ince the 1 4
contact opens at about the 3 s econd point.
T i m e d R e c l o s e O pe r a t i on s
At 7 s e conds a # 5 cam screw will reset the Y
unit , s e tting u p the c i rcuits for the next reclose try.
At 1 5 s ec on ds , if the bus or the line is d e ad w ith the
other s ide hot or if both sides are e ne rgized and i n
s ynchronism , a reclos e w i l l oc cur s hould the first
rec los e be unsu c c e ss fu l . In any c as e , the drum will
continue to rotate and w ith the breaker o pe n a similar
reclose will occur at 4 0 s e c on ds if allowed by the
CVE re lay or the voltage units . The drum continues
to rotate with the breaker open until 4 8 s e c onds . If
the breaker i s open at this point, th e # 4 c ontact
c losure ene rgizes SG re lay 79-4X which s e ts u p the
RC for a synchronism check reclose whenever the
line is re stored . The motor c ontinues to run until
50 s ec . , when the #3 c ontact c los e s . #3 contact
en ergiz e s the 7 9-4Y coil through the 7 9-4 X contac t ;
a 7 9-4 Y break contact then stops the m otor . T h e # 3
contact also c ompletes the circuit through the C V E
unit c ontact s o that reclosing w i l l take place when
synchronism occurs . The 79-4X break contac t in
s e ri e s with the bus and line voltage contacts V1 and
V 2 prevents reclosing at this point for any c ondition
other than synchronis m . A 79-4Y c ontac t , connected
to an external d e lay timer , can be used to alarm for
this intermediate lockout state.
After the perm anent fault i s removed from the
line and the line is ene rgiz ed from the remote station,
1 1
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