Westinghouse KC-4, Инструкция по установке, эксплуатации и обслуживанию

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TY P E S SC, SC-1, SV AND SV-1
COIITACTS - EI THER
NUE OR IRUK AS
IE�JUIIED
IOTTQM UMIT
III TERUL SCHEMATIC
TOP LEfT KAIIO U II I T
( FIIOIIT V I EK)
TOP II I IM I T tiAIID U ii i T
{FROIIT � l EW)
JE$T SW I TCti
TEiNIIIAL
183Al92
Fig.
7.
Internal Schemati c of the Three Uni t Type S V o r
SV- 1 Relay i n the Type F T32 Case.
which are attached to the base terminals. These
sleeves are notched at their upper ends , and the not­
ches are tow ard the center of the relay . The lead s are
bent at approximately a right angle where they p ass
out through the notches, which aids in preventing them
from coming into contact with the stationary contact
brackets. Figure 11 sho w s properly coiled and assem­
bled moving contact leads.
Although the movin g contact l eads are very flexi­
ble, if the leads have been pulled out of their original
shape by handling they may exert sufficient side pres­
sure on the shaft bearing or twisting force against
the guide post to cause appreciable friction and wear.
If this condition continues for a long p eriod of time ,
the resulting wear may affect the relay calibration o r
o r the dropout ratio noticeably. In extreme cases the
wear may progress to a degree which may occasionally
cause failure of the plunger to drop down when the re­
lay is de- energized.
Correct shaping of the leads is not difficult, and
they may be checked readily by removing the guide
post and the nut at the top of the shaft. The plunger
should be held in the raised po sition, either by ener­
gizing the relay or by pressing lightly against the
6
Curve 143285
I t
-
-
' S SV-t,SC and SC-I Relays on D.C.
11ax.
or 11in. Settinq
·
- -
- -
1.0
SVantl SV-1
·
1
• ·
J
I
sc
and 60
. 11ax.
sellin
1
,
1
i
H�n. Settin
_
I
i\ii
100
zoo
400 600 800 !000
Perunt of
Pick-up
Settin9 on
SC
or
SC-I
Relay
(60
Cycles)
100 150
zoo
250 300
Percent of Pick-up Settinq on SVor
sv-1
Reloy and on SC
or
SC I
Relay Used on D.C.
Fi g.
8.
Typi cal Time Curves fo r the Types SC one/ SV
Relays (Using Flux Shunt for Pick -up A djustm ent.)
collar under the insulation plate after rai sing the
plunger manually. With the plunger raised, the insul­
ation plate sheuld be o scillated slightly in a horizon­
tal plane by twisting it horizontally and releasing it.
If in several trials the plate comes to rest with the
center line of the contacts approximately parallel to
the base and with its mounting hole fairly well center­
ed with the end of the shaft, if the plate does not tip
appreciably, and if the leads have a safe clearance to
the stationary contact brackets, the l eads are properly
shap ed.
If this check shows that re- shaping is necessary,
it may be possible to obtain sufficient correction by
bending the leads sharply where they emerge from the
insulation sleeves. One or two pairs of tweezers are
tools for re- shaping the leads. If it is necessary to
re-coil the leads, they should be wound around a rod
having a diameter of approximately 5/32 " . The coils
then should be stretch ed o ut j ust enough to avoid side
pull or twisting force on the plunger assembly.
In all relays except the SV- 1 relay for A-C , if the
stationary contacts are assembled so that they clo s e
when the relay is energized, they should b e located
so that they barely touch the moving contacts when
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