Westinghouse KP Instructions Manual

CAUTION: B efore p utting relays into serv ice, re­
mov e all blocking which may hav e been inserted for
the purpose of s e curing the parts during s hipment,
make sur e that all mov i ng parts operate fre elY, in­
spe c t the contacts to see that they ar e clean an d
close properly, and operate the relay to che ck the
setting s and electrical connections.
APPLICATION
The type KP re lay is a three phase hig h spe ed
voltag e and phase sequenc e relay.
Th is relay can be used as e ither an underv oltag e
or ov erv oltage fault detector. In addition, it can also
be use d to check phase s e qu e nce of a thr e e .P hase
v o ltage.
C ONSTRUC TION AND OP ERATION
an
The type KP relay consists of a hig h speed
cylinder unit with adjustable spring and an in­
dicating cont actor switch when re quired.
Voltage Unit
The voltag e unit is a product induction cylinder
typ e unit.
Mechanically, the overcurrent u nit is composed
ofthree basi c components: a die-cast aluminum fram e
and electromag net, a moving e lement assembl y , and
a molded bridg e .
The frame serv e s as the mounting structure for
the mag n etic core. The Irag netic core which houses
the lower pin bearing is .o e c ured to the frame by a
spring and snap ring . The b e ar ing can be replaced,
if nece ssary, without hav ing to remov e the m ag n etic
core from the frame .
The el ectromag net has two pairs of coils. The
coils of each p air are mounted diametrically opposite
one another. In addition, there ar e two locating pins.
The locating pi ns are used to accurately position the
lower pin b e aring , which is mounted on t h e frame,
with r e spe ct to the upper pin bearing,
SUPERSEDES LL. 41-222.4
*Denotes change from superseded issue.
INSTALLATION
I N S T R U C T I O N S
TYPE KP THREE PHASE VOLTAGE
AND PHASE SEQUENCE RELAY
which is
Westinghouse
•
OPERATION
threaded i nto the bridg e .
permanently se cured t o the frame
s epar at e d from the frame.
The mov i ng el ement
spiral spring, contact
aluminum cylinder assembled to a molded hub which
holds the shaft. The shaft ha s remov able top and
bottom j e wel bearing s . The shaft rides between the
bottom p in b e ar ing and the upper pin b earing with the
cylinder rot ating in an air g ap formed by the elec­
tromagnet and the mag netic core .
The bridg e is secured to the electromag net and
frame by two mounting scre ws. In addition to holding
the upper pin bearing, the bridg e is used for mounting
the adj ustable stationary
stationary contact hous ing i s held in position by a
spring type clamp. The spring adj uster is located o n
the underside of the bridg e and is attac he d t o the
mov ing contact arm by a spiral spring . The spring
adj uster is also held
clamp .
With the contact s closed, the ele ctrical conn e c­
tion is made throug h the stationary contact housing
clamp, to the mov i ng
spring o ut to the spr ing adj uster clamp .
The voltag e at which the contacts e ither pickup
or dropout can be v aried by me ans of moving the
spring adjuster.
Indicating Contactor Switch Unit (ICS)
Th e indicating contactor switch is a small d- e
operated clapp er type dev ice. A mag netic armature,
to which l eaf- spring mounted contacts are attac he d ,
is attracted t o t h e mag netic core upon e nerg i zation
of the switch. When the s witch close s, the mov i ng
contacts bridg e two stationary contacts, completing
the trip circuit. Also during this operation two fing ers
on the armature deflect a spr i ng located on t he front
of the switch, which allows the operation indicator
target to dr op. The targ et is re s et from the outside of
the case by a push rod located at t he bottom of
the c ov er .
EFF ECTIVE OCTOBER 1969
LL. 41-222.4A
•
MAINTENANCE
The electromag net
and cannot b e
assembly consists of a
c arrying member, a nd
contact housing . The
in plac e by a spring typ e
contact, throug h the spiral
i s
a n