GE AK-50 - Direct-Acting Overcurrent Tripping Device EC-1; Long Time-Delay Tripping (EC-1); Instantaneous Tripping (EC-1)

Gff
-
74600
low
-
vp
/
foge
Powmr
Circuit
Breakers
3
.
Place
a
1
/
32
-
in
.
gage
between
imagnet
(
22
)
and
armature
(
18
)
.
4
.
Push
the
armature
solidly
against
the
magnet
with the
gage
in
place
.
The
breaker
should
trip
.
25
24
23
£
C
/
£
ADJUZTABU
H
/
$
H
-
5
£
T
/
/ /
SI
22
5
.
If
the
breaker
does
not
trip
,
turn
the
adjusting
screw
(
10
)
,
and
repeat
steps
1
and
2
.
21
6
.
This
adjustment
must
be
made
for
both
armatures
.
t
i
1
7
.
When
the
armatures
are
resting
against
the
adjusting
screws
(
25
)
and
the
breaker
is
reset
,
there
should
be
1
/
32
-
in
.
clearance
between the
adjust
-
ing
screw
(
10
)
and
trip paddle
(
9
)
.
4
+
4
Q
,
U
-
1
I
e
n
&
:
12
DIRECT
-
ACTING
TRIPPING
DEVICES
EC
-
1
A
and
EC
-
1
B
(
Fig
.
23
)
14
15
16
(
USED
ON
AK
-
2
-
75
AND
AK
-
2
-
100
)
17
The
Type
EC
-
1
A
or
EC
-
IB
over
-
current
tripping
device
is
a
direct
-
acting
device
that
causes
the
power
circuit breaker with which
it
is
asso
-
ciated
to
open
within
a
predetermined
time
range
which
depends
upon
the
magnitude
of
the
current
overload
.
The
EC
-
1
A
or
EC
-
IB
tripping
devices
can
be constructed
to
supply
a
variety
of
different
types
of
time
-
current
charac
-
teristics
,
either alone
or
in
combina
-
tion
.
These
are
longtime
delay
,
short
time
delay
,
and instantaneous
,
and
they
are
identified
respectively
by
numbers
1
,
2
and
3
.
Characteristics
are
further
broken
,
down
within each
of
the
first
two
of
these
general
classifications
into
maximum
,
intermediate
,
and
mini
-
mum
values
of
the
time
delay
period
.
These
are
coded
respectively
as
AA
,
BB
and
CC
.
Time and
current
rela
-
tionships
for
the
various
device
charac
-
teristics
are
given
by
curve
drawing
289
B
198
,
2
18
1
.
S
.
T
.
D
.
Armature
2
.
Pallet
3
.
Pinion
4
.
Escape
Wheel
5
.
Driving
Segment
6
.
S
.
T
.
D
.
Calibration
Spring
7
.
S
.
T
.
D
.
TripAdj
.
8
.
T
rip
Link
9
.
Air
Gap
Adj
.
10
.
Connecting
Rod
11
.
Magnet
12
.
Trip
Paddle
1
3
.
Lock
Nut
14
.
L
.
T
.
D
.
Armature
15
.
Inst
.
Calibration
5
pring
16
.
L
.
T
.
D
.
Calibra
-
tion
Spring
17
.
Calibration
Clamp
Nut
27
.
Connecting
Rod
16
.
Dashpot
Fig
.
23
.
Dlrecf
-
octing fnpping
device
19
.
Clamp
20
.
Stud
21
.
Calibration
Scale
22
.
Inst
.
Calibration
Spring
(
High
Set
)
23
.
Clamping
Nut
24
.
Calibration
Washer
25
.
Armature
26
.
Magnet
£
C
-
M
and
EC
-
JB
conjunction
with
any
other character
-
istic
is
always high
-
set
,
non
-
adjust
-
able
on
the
EC
-
1
A
.
SHORT
TIME
-
DELAY
TRIPPING
(
Fig
.
23
)
The short
time
delay
armature
(
1
)
is
restrained
by
a
calibration
spring
(
6
)
.
If
the
force
tending
to
close
the
armature
against
the
magnet
(
11
)
is
great
enough
to
overcome
the
spring
force
,
the
speed
of
movement
is
gov
-
erned
by
the mechanical
escapement
mechanism
consisting
of
parts
(
2
)
,
(
3
)
,
(
4
)
and
(
5
)
.
A
single
EC
-
1
A
or
EC
-
lBovercur
-
rent
device
may
incorporate
the
same
combination
of
tripping
characteristics
described
under
the
EC
-
1
DIRECT
ACTING
DEVICE
.
The
EC
-
1
A
and
EC
-
IB
tripping
de
-
vices
differ
only
in
that
the
EC
-
IB
is
adjustable
on
high
-
set
instantaneous
tripping
.
The
EC
-
1
A
is
not
adjustable
on
high
-
set
instantaneous
tripping
and
its
pickup
value
for
this
setting
is
given
in
a
particular
current
magnitude
in
-
scribed
on
the device
nameplate
.
The
adjustable
setting
mechanism
of
the
EC
-
IB
is
shown
at
the
top
of
Fig
.
23
.
Whenever
either
armature
(
1
or
14
)
closes
against
the
magnet
(
11
)
,
motion
is
transmitted
through
the mechanism
linkage
,
rotating tripping
link
(
8
)
so
that
connecting
rod
(
10
)
is
pulled
to
-
wards
the
rear
of
the breaker
.
By
means
of
trip
paddle
(
12
)
this
results
in
the
displacement
of
the breaker
mechanism
trip
latch which
causes
the
breaker
to
trip
open
.
Long
and
short
time
delay
tripping
is
achieved
through
seoarate
timing
devices
as
described
LONG
TIME
-
DELAY
TRIPPING
{
fig
.
23
)
S
.
Low
-
set
instantaneous
tripping
is
adjustable
from
80
percent
to
250
per
-
s
*
centof
the
continuous
current
rating
of
Ithe
device
.
Whenever
this
is
used
,
it
is
the
only
characteristic
of
the
de
-
The
long
time
delay
armature
(
14
)
is
restrained
by
the
long
time
delay
calibration
spring
(
16
)
.
After
the
mag
-
netic
force
produced
by
the
overcur
-
rent
condition
overcomes
this
re
-
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