GE AK-50 - EC-1 Tripping Device Replacement and Adjustments; EC-1 Tripping Device Replacement; EC-1 Tripping Device Adjustments; Series Overcurrent Tripping Device EC-1

Low
-
voltag
*
Power
Circurf
Breakers
GBI
-
74600
REPLACEMENT
(
Fig
.
23
)
movement
ifi
governed
by
the
flow
of
oil
through
an
orifice
in
the
piston
of
the
dashpot
(
18
)
.
The
time
required
to
displace
the
piston
is
inversely
pro
-
portional
to
the
force
tending
to
close
the
magnetic
circuit
.
be
made
is
the
length
of
the
connecting
rod
(
10
)
.
This
is
made
by
varying
the
amount
of
thread
engagement
between
the
connecting
rod
and
the
insulated
coupling
which
ties
onto
the
trip
pad
*
die
(
12
)
.
The
approximate
distance
between
the
pivot
centers
on
the
ends
of
the
connecting
rod
assembly
is
six
inches
.
The
correct
exact
distance
is
that
which
will
just
cause
tripping
of
the
breaker
when
the
armature
is
closed
to
a
point
1
/
32
in
.
short
of
con
-
tact
with
the
magnet
.
A
step
-
by
-
step
procedure
for
making
this
adjustment
follows
.
r
)
1
.
Disconnect
trip
paddle
(
12
)
and
connecting
rod
(
10
)
by
taking
out
cotter
pin
and
removing
coupling
pin
.
2
.
Remove
clamp
(
19
)
by
loosening
locking
nut
and
unscrewing
slotted
stud
.
INSTANTANEOUS
TRIPPING
(
Fig
.
23
)
3
.
Remove
stud
(
20
)
.
High
-
sot
,
Non
-
adjustable
4
.
Remove
two
screws
fastening
magnet
(
11
)
to
lower
stud
.
When
an
overcurrent
is
of
the
mag
-
nitude
of
the
instantaneous
trip
setting
,
the
magnetic
force
generated
is
great
enough
to
extend
the
instantaneous
spring
(
15
)
,
tripping
the
breaker
in
-
stantly
.
If
the
overcurrent
is
below
this
value
,
the
heavy
instantaneous
spring
acts
as
a
link
,
transmitting
the
force
to
the
other
control
elements
.
If
the
device
has
only
the
instantaneous
characteristic
,
the
front
end
of
spring
(
15
)
is
hooked
onto
a
pin
fastened
on
the
frame
.
r
5
.
Device
is
now
free
of
breaker
.
Reassembly
is
accomplished
by
re
-
versing
the
procedure
.
1
.
Before
mounting
the
trip
device
,
set
the
center
distance
between
the
pivot
centers
of
the
connecting
rod
at
six
inches
.
2
.
Mount
the
device
as
described
under
replacement
and
insert
the
pin
which
couples
the
connecting
rod
and
the
trip
paddle
.
3
.
Close
the
breaker
and
insert
a
feeler
gage
1
/
32
in
.
thick
between
the
armature
and
magnet
.
This
should
be
done
from
the
rear
of
the
breaker
.
The
feeler
gage
should
be
no
wider
than
1
/
2
in
.
and
at
least
4
inches
long
.
When
reassembling
the
magnet
to
the
lower
stud
,
be
sure
to
replace
any
spacing
washers
in
the
same
location
in
which
they
were
found
during
dis
-
assembly
.
If
this
is
not
done
,
mis
-
alignment
and
consequent
malfunction
may
result
.
ADJUSTMENTS
(
Fig
.
23
)
High
-
set
,
Adjustable
—
EC
-
1
B
Only
Adjustable
instantaneous
tripping
is
accomplished
by
varying
the
amount
of
tensile
force
on
the
high
-
set
instan
-
taneous
spring
(
22
)
.
When
a
magnetic
force
greater
than
the
restraining
spring
force
is
produced
by
an
over
-
current
condition
,
the
armature
(
25
)
is
pulled
upward
against
the
magnet
(
26
)
,
thus
tripping
the
breaker
by
the
movement
of
the
connecting
rod
(
27
)
against
the
trip
paddle
(
12
)
.
Before
the
EC
-
1
A
or
EC
-
IB
over
-
current
device
is
calibrated
at
the
fac
-
tory
,
the
air
gaps
between
magnet
(
11
)
and
armatures
(
1
and
14
)
are
set
.
These
gaps
are
measured
at
their
wid
-
est
point
,
between
the
front
edge
of
the
armature
and
magnet
.
The
gap
for
the
short
time
delay
armature
is
11
/
64
in
.
,
and
for
the
long
time
delay
armature
is
17
/
64
in
.
Both
have
a
plus
and
minus
tolerance
of
1
/
64
in
.
4
.
Close
the
armature
against
the
gage
and
magnet
.
k
5
.
If
the
breaker
does
not
trip
,
shorten
the
length
of
the
connecting
rod
(
10
)
gradually
until
it
does
.
6
.
Check
visually
to
make
sure
that
the
connecting
rod
does
not
restrict
the
engagement
of
the
breaker
trip
latch
when
the
breaker
mechanism
resets
.
It
should
always
be
possible
to
adjust
its
length
to
a
point
where
resetting
is
not
interferred
with
and
yet
positive
tripping
by
the
overcurrent
device
is
achieved
.
SERIES
OVERCURRENT
TRIPPING
DEVICE
EC
-
1
(
Fig
.
24
)
(
USED
ON
AK
-
50
ONLY
)
Each
series
overcurrent
tripping
device
is
enclosed
in
a
molded
case
and
mounted
by
three
screws
and
a
bracket
to
the
lower
part
of
the
pole
unit
base
.
The
pickup
value
of
the
device
may
have
one
of
the
following
ranges
:
4
to
9
,
6
to
12
,
or
9
to
15
times
coil
rating
.
Three
calibration
marks
will
appear
on
the
calibration
scale
(
21
)
and
the
value
of
these
calibration
marks
will
be
indicated
by
stampings
on
the
scale
as
follows
:
(
4
X
-
6
.
5
X
-
9
X
)
or
(
6
X
-
9
X
-
12
X
)
or
(
9
X
-
12
X
-
15
X
)
,
depend
-
ing
on
the
desired
range
.
To
set
the
device
at
a
particular
pickup
value
,
loosen
the
clamping
nut
(
23
)
and
slide
the
index
pointer
on
the
calibration
washer
(
24
)
to
a
position
which
lines
up
horizontally
with
the
desired
pickup
value
on
the
calibration
scale
(
21
)
.
The
air
gap
setting
is
a
factory
ad
-
justment
and
is
not
to
be
attempted
in
the
field
.
If
any
change
occurs
,
the
calibration
of
the
device
will
not
be
true
.
If
any
calibration
difficulties
are
experienced
,
they
may
be
due
to
the
fact
that
the
air
gap
setting
has
been
altered
by
rough
handling
or
ship
-
ment
damage
.
If
a
check
of
the
air
gap
measurement
reveals
that
the
setting
is
beyond
the
tolerance
,
the
device
should
be
returned
to
the
factory
for
recalibration
.
c
The
adjustment
screw
(
7
)
is
pro
-
vided
so
that
the
short
-
time
mecha
-
nism
will
pick
up
the
trip
link
(
8
)
at
the
same
point
at
which
it
is
picked
up
by
the
long
-
time
mechanism
.
This
may
be
checked
before
the
device
is
mounted
by
pulling
forward
on
the
connecting
link
(
10
)
and
checking
visually
to
see
that
trip
link
(
8
)
contacts
both
the
set
pin
in
the
long
time
linkage
and
the
end
of
adjustment
screw
(
7
)
.
The
device
can
be
provided
with
the
same
tripping
combinations
as
the
EC
-
1
direct
acting
device
.
Low
-
set
,
Adjustable
If
the
characteristic
of
the
device
is
low
-
set
,
adjustable
-
instantaneous
,
a
link
is
installed
in
place
of
spring
(
15
)
and
the
instantaneous
calibration
spring
is
located
where
spring
(
16
)
is
Z
?
shown
in
Fig
.
23
.
Dashpot
(
18
)
is
omitted
from
the
assembly
.
SHORT
TIME
-
DELAY
TRIPPING
(
Fig
.
24
)
The
armature
(
7
)
is
restrained
by
calibrating
spring
(
8
)
.
After
the
mag
-
After
the
device
is
mounted
on
the
hreaker
a
final
aHinefmunt
that
muct
Vi
.
r
n
*
-
i
Attor
^
n
rvnn
*
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