T Y P E CO CIRCU I T O P E N I N G RE LAY
OPERAT IOM IMOICATOR
AUX. CURRENT
TRANSF. SECONDARY
TEST SW ITCH
NOTE: TERM.
2
AIID 8 ARE TO BE
JUMPERED AT RELAY CASE
INTfRNAL SCHEMATIC
FROIIT YIEV
DE·IOH
CONTACTOII
SWITCH
AUX. CURRENT
TRAMSF.
PRIMARY
IMOUCTIOit UN IT
CHASSIS
OPEUTIO
SttORTIIIQ SWITCH
URREIIT TEll JACj�:
T
EIIM
I
N
AL
SUB. 2
183A055
Fig.
J.
Internal Schematic of the Circuit Opening Type
CO R e lay in Type F T2 l Case.
magnetic
core upon energization of the switch.
When the switch closes two fingers on the armature
deflect a spring located on the front of the switch,
which allows the operation indicator target to drop.
The front spring, in addition to holding the
target, provides restraint for the armature and thus
controls the pickup value of the switch.
INDICATING INSTANTANE OUS TRIP UNIT (liT)
The instantaneous trip unit is a small a-c oper
ated clapper type device.
A magnetic armature, to
which leaf-spring mounted contacts are attached, is
attracted to the magnetic core upon energization of
the switch.
When the switch closes , the moving
contacts bridge two stationary contacts completing
the trip circuit.
Also, during the operation , two
fingers on the armature deflect a spring located on
the front of the switch which allows the operation
indicator target to drop.
A core screw accessible from the top of the
switch provides the adjustable pickup range.
2
INTERNAL SCHEMATIC
OE-JOH
COHTACTOR SW I TCH
OPERATION IND ICATOR
AUX. CURRENT
TRAHSF. Pill�.
AUX. Ci.JIIUHT
TRAHSF. SECONDARY
INDICATING
INSTAIHAHEOUS
TR IP UltiT
!IWUCTIOM UII IT
CMASSIS OPEIIATED
SHORTING SW' ITCII
TEST S .. ITCH
TERMINAl
FRONT YIEV
SUB. 3
ltOTE:
TERM.
2
AHO 8 All[ TO fiE
JUMPEIIED AT RELAY CASE
183A054
Fig. 2. Internal S chematic of the Circuit Opening Type
CO Rttlay, With Indicating Instantaneous Trip,
in Type F T2l Case.
CHARACT ERIST I CS
The relays are available in the following current
range:
R
_______
_I_i\..P_§._
..
_______ _
4 - 1 2
4
5
6
7
8
1 0
12
ThP
circuit-opt'nin.l.': relay is rL•cornmendPd only
in the
-1 t
o
12
ampere range.
l\
lo\\Cr rangP
is
not
dPsirahh' lwcausP the burden of a
low-range trip
coil is
too
heavy on thP curn'nt transformPr. One
trip coil is fl'CJUired for Pach relay.
The burden of the
auxiliary
current t ransformer at
0 4 amps. is 4.6
VA
with contacts IIT or
CO
closed
and 5.7
VA
wit
h
contacts open.
The ti!llt' 1·s. currl'nt charactnistics
are
s
h
o
w
n
in
Figs. :3
to
9.
Thl' se charactl'ri stic s give
the
con
tact closing timl' for
tlw
rarious
tinH'
dial sdtings
1\hen
Uw i
n
di
c
at
e
d multipll'S of tap value current
are applit'd
to
ttll'
fl'la.y.
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