T Y P E S CA- 1 6 AND CA-26 R E LAYS
MOTE;
WITH REUTIYE IIISTAM
TAIIEOUS POLA R I T I E S AS
SHOWII. THE AMPERE
TURIIS 1M THE PAIRED
RESTRAIIIMG COILS ADO
TO PRODUCE MAXIMtJM
TOft
QUE .
INTERNAL SCHEMATIC
SOTIIJol
LEFT
HMO
ELDOT
( F . V . )
A.UTO TRAMSFORMER
, CHASS I S OPERATED
SHORTIMG SWITCH
- RED HAIIDLE
- TEST SWITCH
CURREIIT T£ST J.I.CK
TERM I MAL
185A419
Fig. 3 . Internal Schematic
o f
the Type CA- 1. 6 B us Relay
laminated
electromagnet with an auto-transformer
winding on its c enter leg. TWo identical coils on the
outer legs of the laminated structure are connected
to the second ary (tapped section) of the auto-trans
former winding in a manner so that the c ombination
of all fluxe s produced by the electromagnet results
in out-of-phase fluxes in the air g ap. The out-of
phase air gap fluxe s c ause a contact closing torque.
S e n s i t i v e F a u l t D etector C i rc u i t ( w h e re u s e d )
The sensitive fault detector circuit c onsists of
an auto-transformer and a contactor switch. The c on
tactor switch is connected across the secondary
(tapped section) of the auto-transformer winding.
The c ontactor switch is a small solenoid t yp e
element. A cylindrical plunger rides up and down on
a vertical guide rod in the center of the solenoid coil.
The
guide rod is fastened to the stationary core ,
which in turn screws into the un it fram e . A silver
disc is fastened to the moving plunger through a heli
c al spring. When the coil is energize d , the plunger
moves upward c arrying the silver disc whic h bridges
three conical- shaped
stationary contacts. In this
position , the helic al spring is compre ssed and the
plunger is free to move while the contact remain s
stationary. Thus, a-c vibrations of. the p lunger are
prevented from c ausing contact bouncing. A Micarta
disc is fastened to the bottom of the guide rod by
BOTTOf.I R I G H T IIA.ND
HEMEMT ( F . V . )
TOP LEFT MAllO
ElEMEIIT { F . V . )
MOTE:
WITH RELATIVE I IISUN
UMEOUS POLAR I T I E S AS
SHOWll , THE AMPEIIE
TURNS 1M TKE Po\JRED
RESTRA I M I M G CDILS
ADO TO PRODUCE MAXI·
MUM TORQUE.
INTERNAL SCHEMATIC
AUTOTR.I.IISFORMER
IIIDICATIIIG
IIISUIIUIIEOUS
TRIP ATUCHMEMT
TOP itUT·IAID
ELEMEIIT ( F . V . )
- CHASSIS O�'ERATEO
SHOR T I M G SWITCH
- TEST SWITCK
CURRENT TEST JACK
TERMINAL
185A443
Fig.
4.
Internal Schematic
of
the Type CA-26 Trans former
R e lay
two small nuts. Its position determines the pick up
current of the element.
The
auto-transformer is designed to saturate at
high v alues of current to limit the amount of curren t
to the contactor switch.
I n d i c at i n g C o n t a c t o r Sw i t c h U n it ( I C S)
The d-e indicating contactor switch is a small
clapper type device. A m agnetic arm ature , to which
leaf-spring mounted contacts are attached , is at
tracted to the m agnetic core upon e nergization of the
switch. When the s witch closes, the moving contacts
bridge two stationary contacts , completing the trip
circuit. Also during this operation two fingers on the
armature deflect a spring located on the front of the
switch, which allows the operation indic ator target
to drop. The target is reset from the outside of the
case by a push rod located at the bottom of the cover .
The front spring , in addition to holding the target,
provides restraint for the armature and thus controls
the pick-up v al ue of the s witch.
I n d i c at i n g I n sta n t a n e o u s T r i p U n i t ( l i T }
The instantaneous trip unit is a small a-c operated
clapper type devic e . A magnetic armature , to which
le af- spring
mounted contacts are attached , is at
tracted to the magnetic core upon energization of the
3
www
. ElectricalPartManuals
. com
