GE GCX51A - Acceptance Tests; Visual Inspection

GEI
-
98328
The
relay
mechanism
is
mounted
in
a
steel
framework
called
a
cradle
,
and
is
a
complete
unit
with
all
leads
being
terminated
at
the
inner
block
.
This
cradle
is
held
firmly
in
the
case
with
a
latch
at
both
top
and
bottom
and
by
a
guide
pin
at
the
back
of
the
case
,
connections
between
the
respective
blocks
of
the
cradle
and
case
,
also
locks
the
latch
in
place
.
The
cover
,
which
is
drawn
to
the
case
by
thumbscrews
,
holds
the
connecting
plugs
in
place
.
A
separate
testing
plug
can
be
inserted
in
place
of
the
connecting
plug
to
test
the
relay
in
place
on
the
panel
,
either
from
its
own
source
of
current
and
voltage
,
or
from
other
sources
.
Or
the
relay
can
be
drawn
out
and
replaced
by
another
that
has
been
tested
in
the
laboratory
.
The
connecting
plug
,
besides
making
the
electrical
The
relay
is
composed
of
three
major
sub
-
assembly
elements
:
1
.
The
bottom
element
includes
the
MHO
or
starting
unit
and
associated
circuit
components
.
This
unit
is
directional
and
detects
the
presence
of
faults
within
the
zone
covered
by
the
relay
.
It
also
initiates
operation
of
the
zone
timer
for
faults
within
its
reach
.
The
middle
element
includes
the
OHM
or
reactance
unit
and
associated
circuit
components
,
measurement
.
2
.
This
unit
provides
accurate
first
-
or
second
-
zone
distance
The
top
element
includes
the
OHM
unit
transfer
auxiliary
(
OX
)
,
the
combination
target
and
seal
-
in
unit
,
the
transactor
associated
with
the
OHM
unit
potential
circuit
,
the
tapped
autotransformer
that
determines
the
reach
of
the
OHM
and
MHO
units
,
and
in
the
case
of
the
type
GCX
51
B
relay
,
the
instantaneous
overcurrent
unit
.
The
tap
block
associated
with
the
autotransformer
is
mounted
along
the
right
side
of
the
relay
.
Figures
1
and
2
show
the
relay
removed
from
its
drawout
case
with
all
major
components
identified
.
Symbols
used
to
identify
circuit
components
are
the
same
as
those
that
appear
on
the
internal
connection
diagram
in
Figure
8
.
3
.
ACCEPTANCE
TESTS
Immediately
upon
receipt
of
the
relay
an
INSPECTION
and
ACCEPTANCE
TEST
should
be
made
to
make
sure
that
no
damage
has
been
sustained
in
shipment
and
that
the
relay
calibrations
have
not
been
disturbed
.
that
readjustment
is
necessary
,
refer
to
the
section
on
SERVICING
.
If
the
examination
or
test
indicates
Visual
Inspection
Check
the
nameplate
stamping
to
make
sure
that
the
model
number
and
rating
of
the
relay
agree
with
the
requisition
.
Remove
the
relay
from
its
case
and
check
that
there
are
no
broken
or
cracked
molded
parts
or
other
signs
of
physical
damage
,
and
that
all
screws
are
tight
.
15
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