GE AK-50 Series - Direct Acting Tripping Device EC-1 B; EC-1 B Short Time-Delay Tripping; EC-1 B Long Time Delay Tripping; EC-1 B Instantaneous Tripping

GEK
-
7303
Low
Voltage
Power
Circuit
Breakers
aneous
,
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
minimum
values
of
the
time
delay
period
.
These
are
coded
resDectivelv
as
AA
.
BB
and
CC
,
Time
and
current
relationships
for
the
various
device
characteristics
are
given
by
curve
drawing
2
89
B
198
.
The
EC
-
IB
is
adjustable
on
high
-
set
instan
-
taneous
tripping
.
The
adjustable
setting
mechanism
of
the
EC
-
IB
is
shown
in
Fig
.
26
.
Low
-
set
instantaneous
tripping
is
adjustable
from
faO
percent
to
250
percent
erf
the
continuous
current
rating
of
the
device
.
Whenever
this
is
used
,
it
is
the
only
characteristic
of
the
device
.
Instantaneous
tripping
used
in
conjunction
with
any
other
characteristic
is
always
high
-
set
.
When
armature
(
1
or
22
)
closes
against
the
mag
-
net
(
11
)
,
motion
is
transmitted
through
the
mech
-
anism
linkage
,
rotating
tripping
link
(
8
)
so
that
connecting
rod
(
10
)
is
pulled
towards
the
rear
of
the
breaker
.
By
means
of
trip
paddle
(
14
)
this
results
in
the
displacement
of
the
breaker
mech
-
anism
trip
latch
which
causes
the
breaker
to
trip
open
.
Long
and
short
time
delay
tripping
is
achieved
through
separate
timing
devices
as
described
below
:
SHORT
TIME
-
DELAY
TRIPPING
(
Fig
.
26
)
UNDERVOLTAGE
LOCKOUT
DEVICE
TYPE
AK
-
50
,
75
&
100
Fig
.
25
(
8039985
)
Right
side
view
of
mechanism
frame
Breaker
shown
in
open
position
.
The
short
time
delay
armature
(
1
)
is
restrain
-
ed
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
governed
by
the
mechani
-
cal
escapement
mechanism
consisting
of
parts
(
2
)
,
(
3
)
,
(
4
)
and
(
5
)
.
)
1
.
Mechanism
cam
2
.
Undervoltage
lockout
arm
3
.
Undervoltage
lockout
lever
4
.
Undervoltage
device
armature
5
.
Undervoltage
device
.
6
.
Undervoltage
lockout
spring
7
.
Mechanism
frame
LONG
T I M E
DELAY
T R I P P I N G
(
Fig
.
26
)
The
long
time
delay
armature
(
22
)
is
restrained
by
the
long
time
delay
calibration
spring
(
15
)
«
After
the
magnetic
force
produced
by
the
over
-
current
condition
overcomes
this
restraint
,
the
velocity
of
the
armature
movement
is
governed
by
the
flow
of
oil
through
an
orifice
in
the
piston
of
the
dashpot
(
17
)
.
The
time
required
to
displace
the
piston
is
inversely
proportional
to
the
force
tending
to
close
the
magnetic
circuit
.
INSTANTANEOUS
TRIPPING
(
Fig
.
26
)
High
-
set
,
Non
-
adjustable
When
an
overcurrent
is
of
the
magnitude
of
the
instantaneous
trip
setting
,
the
magnetic
force
generated
is
great
enough
to
extend
the
instant
-
eous
spring
(
21
)
,
tripping
the
breaker
instantly
.
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
(
21
)
is
hooked
onto
a
pin
fastened
on
the
frame
.
with
the
addition
of
the
lockout
feature
.
The
lockout
feature
consists
of
arm
(
2
)
,
lever
(
3
)
,
and
spring
(
6
)
.
The
lockout
linkage
is
activated
by
die
movement
of
the
mechanism
cam
(
1
)
.
When
the
breaker
is
closed
,
the
undervoltage
device
is
defeated
by
the
lever
(
3
)
holding
the
armature
(
4
)
in
the
closed
air
gap
posi
-
tion
.
When
the
breaker
opens
,
the
mechanism
cam
moves
down
,
allowing
spring
(
6
)
to
rotate
arm
(
2
)
clockwise
which
causes
lever
(
3
)
to
rotate
counter
-
clockwise
to
release
armature
(
4
)
allowing
the
undervoltage
device
to
operate
normally
.
DIRECT
ACTING
TRIPPING
DEVICE
EC
-
IB
(
Fig
.
26
)
(
USED
ON
AK
-
2
-
75
AND
AK
-
2
-
100
)
The
type
EC
-
IB
overcurrent
tripping
device
is
a
direct
-
acting
device
that
causes
the
power
circuit
breaker
with
which
it
is
associated
to
open
within
a
predetermined
time
range
which
depends
upon
the
magnitude
of
the
current
overload
.
EC
-
1
B
tripping
device
can
be
constructed
to
supply
a
variety
of
different
types
of
time
-
current
charac
-
teristics
,
either
alone
or
in
combination
.
These
are
long
time
delay
,
short
time
delay
,
and
instant
-
The
High
-
set
,
Adjustable
—
EC
-
1
B
Adjustable
instantaneous
tripping
is
accomplish
-
ed
by
varying
the
amount
of
tensile
force
on
the
26
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