GE IAC57A - Page 15

Time
Overcurrent
Belays
Type
IAC
GEH
-
1753
CONTACT
ADJUSTMENT
1
.
CONTACT
ADJUSTMENT
With
the
unit
de
-
energized
,
the
movable
contact
should
lie
against
the
stationary
contact
with
enough
tension
to
always
insure
a
good
closed
circuit
.
The
movable
contact
brush
should
be
free
of
any
kinks
.
Also
this
contact
brush
should
not
touch
the
com
-
pound
bushing
supported
from
the
top
of
the
arma
-
ture
.
The
brass
backing
strip
should
be
adjusted
to
allow
a
1
/
16
-
inch
contact
gap
with
the
contacts
open
.
The
compound
bushing
support
should
be
adjusted
to
allow
the
back
of
the
movable
contact
to
just
touch
the
brass
backing
strip
when
the
armature
operates
to
open
the
contacts
.
The
outer
edge
of
the
com
-
pound
bushing
should
be
approximately
1
/
32
-
inch
from
the
inner
edge
of
the
stationary
contact
sup
-
porting
post
.
2
.
ARMATURE
ADJUSTMENT
Loosen
the
two
screws
which
hold
the
armature
-
assembly
bracket
to
the
bottom
of
the
frame
.
Slide
the
bracket
in
or
out
,
whichever
is
necessary
,
until
the
armature
just
touches
the
pole
face
of
the
upper
core
.
In
this
position
,
the
armature
should
be
about
1
/
32
inch
from
the
pole
face
of
the
lower
core
.
Next
,
slide
the
bracket
in
until
the
armature
leaf
spring
assumes
a
vertical
position
and
is
spaced
clear
of
both
armature
and
the
vertical
tip
of
the
bracket
.
With
this
setting
,
the
armature
should
be
flush
against
the
pole
face
of
both
cores
,
and
should
put
enough
pressure
on
the
armature
to
always
re
-
turn
it
*
flush
against
the
pole
face
of
the
lower
core
after
each
operation
of
the
unit
.
This
alignment
is
important
as
a
slight
gap
between
armature
and
pole
face
of
the
lower
core
after
the
unit
operates
may
cause
contacts
to
open
momentarily
,
dropping
the
relay
target
when
the
circuit
breaker
is
reclosed
.
Under
these
conditions
,
the
momentary
opening
of
the
contacts
is
due
to
the
shock
of
the
armature
being
pulled
in
against
the
pole
face
when
the
lower
coil
is
energized
.
Excessive
pressure
on
the
arma
-
ture
,
caused
by
the
bracket
being
pushed
in
too
far
,
will
result
in
too
high
a
pickup
or
chattering
of
the
movable
contact
during
operation
of
the
unit
.
Tighten
the
bracket
screws
securely
after
the
proper
ad
-
justment
has
been
obtained
.
The
contacts
should
have
approximately
1
/
32
inch
wipe
.
That
is
.
the
stationary
contact
should
be
deflected
about
l
/
o
2
inch
when
the
disk
completes
its
travel
.
The
contact
wipe
is
adjusted
by
turning
the
screws
in
the
contact
brush
which
regulates
the
position
of
the
brush
,
in
relation
to
the
brush
stop
.
For
relays
with
two
circuit
-
closing
contacts
,
the
tips
should
be
in
the
same
vertical
plane
.
When
the
time
dial
is
moved
to
a
position
where
the
contacts
just
close
,
the
time
-
dial
scale
should
indicate
zero
.
If
this
is
found
incorrect
,
and
the
brushes
are
correctly
adjusted
,
regulate
the
dial
to
read
zero
.
This
is
done
by
changing
the
position
of
the
arm
attached
to
the
shaft
which
is
located
below
the
time
dial
.
Loosen
the
screw
which
clamps
the
arm
to
the
shaft
and
turn
the
arm
,
relative
to
the
shaft
,
until
the
contacts
just
make
at
the
zero
time
-
dial
setting
.
INSTANTANEOUS
UNIT
Select
the
current
above
which
is
desired
to
have
the
instantaneous
unit
operate
and
set
the
ad
-
justable
pole
piece
so
that
the
top
of
hexagon
head
is
even
with
the
desired
calibration
on
the
scale
.
To
raise
or
lower
the
pole
piece
loosen
the
locknut
and
turn
it
up
or
down
and
then
tighten
in
position
.
The
contacts
should
be
adjusted
to
make
at
about
the
same
time
and
to
have
approximately
1
/
8
"
This
adjustment
can
be
made
by
loosening
wipe
.
the
screws
holding
the
stationary
contacts
and
moving
the
contacts
up
or
down
as
required
.
A
-
C
TRIPPING
UNIT
The
a
-
c
tripping
unit
should
not
require
any
attention
other
than
occasional
cleaning
of
the
con
-
tacts
.
However
,
if
the
adjustment
should
be
lost
,
it
may
be
restored
as
follows
:
OPERATION
The
pickup
current
should
be
checked
on
one
or
more
of
the
taps
and
the
time
should
be
checked
for
one
or
more
dial
settings
.
Before
the
relay
is
put
into
service
it
should
be
given
a
check
to
determine
that
factory
adjustments
have
not
been
disturbed
.
The
time
-
dial
will
be
set
at
zero
before
the
relay
leaves
the
factory
.
It
is
necessary
to
change
this
setting
in
order
to
open
the
relay
contacts
.
Recommended
test
connections
for
the
above
test
are
shown
in
Fig
.
18
.
MAINTENANCE
The
relays
are
adjusted
at
the
factory
and
it
is
advisable
not
to
disturb
the
adjustments
.
If
,
for
any
reason
,
they
have
been
disturbed
,
the
following
points
should
be
observed
in
restoring
them
:
exploring
its
surface
with
the
point
of
a
fine
needle
.
If
it
is
necessary
to
replace
the
jewel
a
new
pivot
should
be
screwed
into
the
bottom
of
the
shaft
at
the
shaft
at
the
same
time
.
The
jewel
should
be
turned
up
until
the
disk
is
centered
in
the
air
gaps
,
after
which
it
should
be
locked
in
this
position
by
the
set
screw
provided
for
this
purpose
.
DISK
AND
BEARINGS
The
lower
jewel
may
be
tested
for
cracks
by
13
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