Westinghouse C0-11, Инструкция по установке, эксплуатации и обслуживанию

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T Y P E CO CI RCUIT O P EN I N G R E LAY
stationary contact s houl d have a m1mmum of
1/32"
wipe. The bridgin g moving contact should touch both
stationary contacts simul tane ously.
ROUTINE MAINTENANCE
All relays should be inspected periodically and
the time of operation should be checked at least
once every year or at such other time intervals as
may be dictated by experience to be suitable to the
particular application. Phantom loads should not be
used in testing induction-type relays because of the
resulting distorted current wave form which produces
an error in timing.
All contacts should be periodicallY cleaned. A
contact burnisher
1t
1 82A836H0 1 is recommended
for this purpose . The us e of abrasive material for
cleaning contacts is not recommended, because of
the danger of embedding small particles in the face
of the soft silver and thus impairing the contact.
CAL I B RATION
Use of the following procedure for calibrating the
relay if the relay has been taken apart for repairs or
the adjustments disturbed. This procedure should
not be used until it is apparent that the relay is not
in proper working order. (See "Acceptance Chec k " )
C O UNIT
1 . CONTACTS
a) By turning the time dial , move the moving con­
tacts until they defl ect the stationary contact
to a position where the stationary c ontact is
resting against its backstop. The index mark
l ocated on th e mo vement frame s houl d coincide
With the "0"
mark
on
the
time dia l .
b)
F o r relays identifie d with a "T " , l ocated at
l ower l eft of stationary c o ntact block, the index
mark on the movement frame wil l c o incide w ith
the
"0"
mark on the time d ial when the s tation­
ary contact has moved through approximately
one-half of its normal defl ection . Therefore ,
with the stationary contact resting against the
backstop , the index mark 1s offset
to
the right of
the
"0"
mark by approximately
. 020".
The
placement of the vanous time dial positions m
line with the index mark w il l give operatin g
times as shown on the res pective time-current
curves.
2. MINIMUM TRIP CURRENT
The adjustment of the spring tension in setting
the minimum trip current value of the relay is most
convenientlY made with the damping magnet removed.
With the time dial set on "0 " , wind up the spiral
spring by means of the spring adjuster until approxi­
matelY 6-3/4 convolutions show.
Set the relay on the minimum tap setting , the
time dial to position 6.
Adjust the control spring tension so that the
moving contact will leave the backstop at tap value
current
+
l . Oo/c and will return to the backstop at tap
value current - 1 . 0% .
3 . TIME C URVE CALIBRATION
Install the permanent magnet.
Apply th e indicated c urrent per Table
I
for per­
manent magnet adjustm ent (e. g. C0-8, 2 times tap
value) and m easure the operating
time .
Adjust the
permanent magnet keeper until the operating time
corresponds to the value of Table I.
ApplY the indicated current per Table I for the
electromagnet plug adjustment (e . g . C0-8 , 20 times
tap value ) and measure the operating time. Adjust
the proper plug until the operating time corresponds
to the value in Table I. (Withdrawing the left h and
plug, front view , increases the operating time and
withdrawing the right hand plug, front view , decreases
the time. ) In adjusting the plugs, one plug should b e
screwed i n completelY and the other plug run i n or
out until the proper operating time has been obtained.
For type
C0- 1 1
relay only, the
1 . 3 0
times tap
val ue operating time from the number
6
time d ial posi­
tion is 54.9 ±5% se conds . It is important that the
1 . 30
times tap value current be maintained accurately . The
maintaining of th1s current accurately 1s necessary
becaus e of the steepness of the s lope of the time­
current characteristic (F1gu re 9.
A 1%
variation in
the
1 . 30
times ta p value c urrent ( including mea surin g
mstrument d eviation) will change the nominal opera­
tin g time by approximately 4%.
If
the operating time
at
1 . 3
times tap valu e is not within these l imits , a
minor adjustment of the control s pring will give the
c orrect operating time without any undue effect on
the minimum p ick-up of the relay . This check is to
be made after the
2
times tap val ue adjustment has
been completed.
Recheck the permanent magnet adjustment. If
the operating time for this calibration point has
changed, readjust the permanent magnet and then
recheck the electromagnet plug adjustment.
15
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