GE AK-4-75 User manual

MAINTENANCE
MANUAL
(
SUPPLEMENT
)
LOW
-
VOLTAGE
POWER
CIRCUIT
BREAKERS
labl
-
8
b
135
B
Supplement
to
GEK
-
7303
This
manual when used
in
conjunction
with Publication
GEK
-
7303
(
Maintenance
Manual
for
the
AK
-
50
,
75
&
100
frame
breakers
)
provides
maintenance
instructions
on
the
breaker models and
trip
devices
tabu
-
lated
below
.
Breaker
Type
&
Mounting
Trip
Device
Type
Frame
Size
(
Amp
)
ECS
SST
Stationary
Drawout
AK
-
4
-
75
,
75
C
AK
-
4
A
-
75
,
75
C
X
3000
AK
-
5
A
-
75
,
75
C
AK
-
5
-
75
,
75
C
X
AK
-
4
A
-
100
X
AK
-
4
-
100
4000
AK
-
5
A
-
100
X
AK
-
5
-
100
*
%
#
m
m
vU
:
»
A
”
I
v
V
AK
-
5
A
-
75
Rear View
•
'
/
%
GENERAL
W
ELECTRIC
Courtesy of NationalSwitchgear.com

PUSH
TO
RESET
\
SHORT
TIME
«
NST
.
PICKUP
GROUND
r
V
FIG
.
1
.
SST
Programmer
Unit
CONTENTS
3
Introduction
3
Type
SST
Overcurrent
Trip
Device
Components
Trip
Characteristics
Flux
Shift
Trip
Device
Troubleshooting
SST
Test
Set
TAK
-
TS
1
False
Tripping
(
Ground
Fault
)
...
Replacement
of
Current
Sensors
.
Cabling
Diagrams
Ground
Fault
Defeat
Cable
3
6
7
10
10
11
1 1
12
13
14
Type
ECS
Overcurrent
Trip
Device
Components
Trip
Characteristics
Cabling
Diagram
14
15
15
16
ECS
&
SST
Time
-
Current
Curves
2
Courtesy of NationalSwitchgear.com

MAINTENANCE
MANUAL
SUPPLEMENT
LOW
-
VOLTAGE
POWER
CIRCUIT
BREAKERS
TM
TM
TYPES
AK
-
75
/
100
WITH
ECS
AND
SST
TRIP
DEVICES
INTRODUCTION
TYPE
SST
OVERCURRENT
TRIP
DEVICE
The
SST
is
a
solid
-
state
,
direct
-
acting
,
self
-
pow
-
ered
trip
device
system
.
Referring
to
Figures
l
through
8
,
it
comprises
the
following
individual
com
-
ponents
:
Programmer
Unit
—
provides
the
comparison
basis
for
overcurrent
detection
and
delivers
the
energy
necessary
to
trip
the breaker
.
Contains
the electronic
circuitry
for
the various
trip
elements
.
Their associ
-
ated
pickup
and
time
delay
adjustments
(
set
-
points
)
are
located
on
the
face
plate
.
Depending
on
the
ap
-
plication
,
programmer
units
may
be
equipped
with
various
combinations
of
Long
Time
,
Short
Time
,
In
-
stantaneous
and
Ground
Fault
trip
elements
.
See
Table
1
for
available
ratings
,
settings
and
trip
char
-
acteristics
.
The
data
in
this
supplement
pertain
to
AK
-
75
and
AK
-
100
frame
breakers
equipped
with
type
ECS
and
SST
solid
-
state
trip
devices
.
The
latter
are
not
treated
in
the
primary
maintenance
manual
(
publica
-
tion
GEK
-
7303
)
covering
these breaker
frame
sizes
.
In
scope
,
this
supplement supplies
the essential
descriptive
and instructional material
applicable
to
the
new
trip
devices
.
Although
breakers
so
equipped
carry
new
type
designations
(
AK
-
4
/
4
A
and
AK
-
5
/
5
A
)
,
the
basic
breakers
and
their other
accessory
devices
are
identical
to
those
equipped
with
Power
Sensor
or
EC
trip
devices
.
Accordingly
,
the
general
operational
and maintenance information contained
in
publication
GEK
-
7303
is
equally
relevant
to
ECS
or
SST
equipped
breakers
and
is
not
duplicated
here
.
In
the
event
that
a
programner
set
knob
is
Note
:
left
untightened
,
the
trip
function
reverts to
operation
at
its
minimum
or
maximum
set
point
value
as
follows
:
Unless
otherwise noted
,
the
contents
of
this
sup
-
plement
are
to
be
interpreted
as
applicable
to
both
the
AK
-
75
and
AK
-
100
frames
.
Except
for
the
pro
-
grammer
and
'
sensor
differences
noted
below
,
the
hardware elements
(
e
.
g
.
,
cabling
,
flux shift
trip
actua
-
tors
and
linkage
)
and the
test
/
adjustment
procedures
are
identical
.
Pickup
Delay
Trip
Element
Min
.
,
Min
.
Max
.
Max
.
Long
Time
X X
Examples
:
Programmer
units without the
Ground
Fault
element
are
identical
;
with
Ground
Fault
,
however
,
the
programmers
have
different
pickup
ranges
.
Sensor
tap
rat
-
ings
also
differ
for
each
frame
.
Short
Time
X X
Instantaneous
X
Ground
Fault
X
X
These instructions do
not
purport
to
cover
all
details
or
variations
in
equipment
nor
to
provide
for
every
possible
contin
-
gency
to
be
met
in
connection
with
installation
,
operation
or
maintenance
.
Should
further information
be
desired
or
should
particular
problems
arise
which
are
not
covered
sufficiently
for
the
purchaser
’
s
purposes
,
the
matter
should be referred
to
the
General
Electric
Company
.
3
Courtesy of NationalSwitchgear.com

n
The
SST
programmer
units
can
be
optionally
equipped
with
trip
indicators
(
targets
)
.
These
are
pop
-
out
,
mechanically
-
resettable
plungers
located
across
the
top
of
the
programmers
front
.
Units
with
a
ground
fault
element
employ
three
(
3
)
targets
:
from
left
to
right
,
the
first
is
for
overload
,
the
second
for
short
circuit
(
actuated
by
the
short
time
and
instan
-
taneous
elements
)
and
the
third
for
ground
fault
.
The
latter
is
omitted
on
units
without
ground
fault
.
0
i
r
i
SOLID
STATE
SWITCH
•
•
FLUX
SHIFT
-
TRIP
COIL
CURRENT
SENSOR
*
"
*
I
TAP
I
I
CHANGER
0
0
-
4
OVERLOAD
Y
I
TARGET
J
LONG
TIME
DELAY
i
TTT
I
T
0
i
LONG
SHORT
TIME
PICKUP
&
DELAY
LOGIC
I
0
’
TIME
Each
target
pops
out
when
its
associated
trip
ele
-
ment
operates
to
trip
the
breaker
.
After
a
trip
,
the
popped
target
must
be
reset
by
hand
.
However
,
ne
-
glecting
to
reset
does
not
affect
normal
operation
of
any
trip
element
or
prevent
the
breaker
from
being
reclosed
.
NEUTRAL
“
OR
”
PICKUP
f
3
(
)
i
I
SHORT
CIRCUIT
TARGET
SL
JL
I
DIFFERENTIAL
TRANSFORMER
_
INSTANTANEOUS
PICKUP
I
J
/
WHEN
\
t
USED
/
GROUND
TARGET
I
GROUND
FAULT
PICKUP
&
DELAY
REGULATED
40
VDC
POWER
SUPPLY
Current
Sensors
—
each
pole
mounts
a
single
sensor
coil
(
CT
)
which
supplies
the
power
and
signal
inputs
necessary
to
operate
the
trip
system
.
Each
sensor
has
four
taps
which
provide
field
adjustment
of
the
trip
device
’
s
continuous
ampere
rating
.
J
I
PROGRAMMER
UNIT
Fig
.
2
.
SST
Block
diagram
The
SST
Ground
Fault
trip
element
operates
on
the
principle
that
the
instantaneous
values
of
current
in
the
three
conductors
(
four
on
4
-
wire
systems
)
add
to
zero
unless
ground
current
exists
.
On
SST
’
s
equipped
with
Ground
Fault
,
the
ground
trip
signal
is
developed
by
connecting
each
phase
sensor
in
se
-
ries
with
a
companion
primary
winding
on
a
ground
differential
transformer
mounted
in
the
programmer
unit
.
Its
secondary
output
is
zero
as
long
as
there
is
no
ground
current
.
When
used
,
the
neutral
sensor
(
fig
.
6
)
is
separately
mounted
in
the
bus
or
cable
compartment
of
the
switchgear
.
In
drawout
construction
,
its
output
is
au
-
tomatically
connected
to
the
breaker
via
secondary
disconnect
blocks
.
See
Figs
.
4
,
5
and
15
.
Application
of
the
Ground
Fault
element
to
4
-
wire
systems
with
neutral
grounded
at
the
transformer
re
-
quires
an
additional
,
separately
mounted
sensor
(
Fig
.
6
)
inserted
in
the
neutral
conductor
;
its
secondary
is
connected
to
a
fourth
primary
winding
on
the
ground
differential
transformer
.
See
Fig
.
15
.
This
“
fourth
-
wire
”
neutral
sensor
is
an
electrical
duplicate
of
the
phase
sensor
,
including
taps
.
Therefore
,
when
taps
are
changed
on
the
phase
sensors
,
those
on
the
neu
-
tral
sensor
must
be
correspondingly
positioned
.
Flux
Shift
Trip
Device
—
a
low
-
energy
,
elec
-
tromagnetic
device
which
,
upon
receipt
of
a
trip
sig
-
nal
from
the
programmer
unit
,
trips
the
breaker
by
actuating
the
trip
shaft
.
See
Fig
.
8
.
COMPONENT
LOCATION
All
components
except
the
neutral
sensor
are
mounted
on
the
circuit
breaker
.
The
phase
sensors
are
mounted
around
the
lower
studs
at
the
rear
of
the
breaker
(
see
Fig
.
4
)
.
The
programmer
unit
and
the
flux
shift
trip
device
are
mounted
on
the
breaker
’
s
front
frame
.
These
components
are
interconnected
by
wiring
harness
and
disconnect
plugs
as
shown
on
the
cabling
diagrams
(
Figs
.
13
and
14
)
.
/
Fig
.
3
.
SST
phase
sensor
with
tap
board
4
Courtesy of NationalSwitchgear.com

connector
Tap
terminal
board
Shorting
strap
Fig
.
5
.
Neutral
sensor
secondary
disconnect
block
(
equipment
mounted
)
.
Fig
.
6
.
SST
neutral
sensor
(
equipment
mounted
)
5
Courtesy of NationalSwitchgear.com

Fig
.
7
.
AK
-
5
A
-
100
(
front
view
)
TABLE
1
—
SST
TRIP
CHARACTERISTICS
SST
PROGRAMMER
ADJUSTMENT
RANGE
(
Set
Points
)
Sensor
Ampere
Taps
Long
Time
Short
Time
Ground
Fault
Frame
Size
(
Amperes
)
Instantaneous
Pickup
Breaker
Type
Pickup
(
=
L
)
Time
Delay
Band
®
(
Seconds
)
Pickup
Time
Delay
Band
®
(
Seconds
)
Pickup
©
Time
Delay
Band
®
(
Seconds
)
©
©
©
©
(
X
)
Multiple
Multiple
Multiple
Multiple
of
X
of
L
of
L
of
X
1200
,
1600
,
2000
,
3000
AK
-
75
3000
Maximum
3
,
4
,
5
,
6
,
8
,
10
(
L
)
-
or
-
1.75
,
2
,
2.25
,
2.5
,
3
*
4
(
L
)
Maximum
0.35
Intermed
.
0.21
Minimum
0.095
.
20
,
.
22
,
.
25
.
30
,
.
35
,
.
4
(
X
)
Maximum
0.30
Intermed
.
0.165
Minimum
0.065
22
.
6
,
.
7
,
.
8
,
.
9
,
1.0
,
1.1
(
X
)
Intermed
.
4
,
5
,
6
,
8
,
10
,
12
(
L
)
/
10
4000
1600
,
2000
,
3000
,
4000
AK
-
100
Minimum
.
18
,
.
20
,
.
22
,
.
25
,
.
27
,
.
30
(
X
)
4
©
X
=
Sensor
ampere
tap
=
trip
rating
©
Pickup
tolerance
is
±
10
%
©
Time
delay
at
lower
limit
of
band
@
6
L
.
®
Time
delay
at
lower
limit
of
band
.
V
(
See
pages
17
and
19
for
applicable
time
-
current
curves
)
6
Courtesy of NationalSwitchgear.com

Flux
shift
trip
device
Fig
.
8
.
AK
-
5
A
-
75
(
front
view
)
“
reset
”
position
.
Loosen
the
jam
nut
,
rotate
the
ad
-
juster
end
until
the
proper
gap
is
attained
,
then
re
-
tighten
the
jam
nut
.
While
operating
the
breaker
,
insure
that
the
actua
-
tor
bracket
does
not
interfere
with
the
buffer
stud
.
Adjust
if
necessary
.
FLUX
SHIFT
TRIP
DEVICE
The
mounting
arrangement
of
this
component
is
il
-
lustrated
in
Figures
8
,
9
and
10
.
An
electromagnetic
actuator
mounted
to
the
left
side
of
the
front
frame
is
coupled
to
the
breaker
’
s
trip
shaft
via
a
trip
rod
driven
by
the
actuator
arm
.
The
actuator
is
a
sole
-
noid
whose
armature
is
spring
-
loaded
and
held
in
its
normal
(
reset
)
position
by
a
permanent
magnet
.
In
this
state
the
spring
is
in
tension
.
The
actuator
is
a
sealed
,
factory
-
set
device
and
re
-
quires
no
maintenance
or
field
adjustment
.
In
case
of
malfunction
,
the
complete
actuator
unit
should
be
re
-
placed
.
When
making
the
electrical
connection
to
the
replacement
unit
,
it
is
recommended
that
the
breaker
harness
be
cut
at
some
convenient
point
and
the
new
actuator
leads
solder
-
spliced
thereto
.
An
alternate
method
is
to
untie
the
breaker
harness
and
remove
the
old
actuator
leads
directly
from
the
female
AMP
connector
on
the
end
of
the
breaker
harness
.
How
-
ever
,
AMP
extraction
tool
Cat
.
No
.
305183
is
re
-
quired
for
this
method
.
As
long
as
the
actuator
remains
in
the
reset
posi
-
tion
,
the
breaker
can
be
closed
and
opened
normally
at
will
.
However
,
when
a
closed
breaker
receives
a
trip
signal
from
the
programmer
unit
,
the
actuator
is
energized
and
its
solenoid
flux
opposes
the
magnet
,
allowing
the
spring
to
release
the
armature
;
this
drives
the
trip
rod
against
the
trip
shaft
paddle
,
trip
-
ping
the
breaker
.
As
the
breaker
opens
,
the
actuator
arm
is
returned
to
its
normal
(
reset
)
position
via
linkage
driven
by
a
bracket
attached
to
the
breaker
’
s
crossbar
.
The
per
-
manent
magnet
again
holds
the
armature
captive
in
readiness
for
the
next
trip
signal
.
See
Fig
.
9
.
CAUTION
:
IN
THE
EVENT
THAT
THE
SST
TRIP
DEVICE
MUST
BE
RENDERED
IN
-
OPERATIVE
TO
ALLOW
THE
BREAKER
TO
CARRY
CURRENT
WITHOUT
BENEFIT
OF
OVERCURRENT
PROTECTION
,
THE
RECOMMENDED
METHOD
IS
TO
SHORTEN
THE
TRIP
ROD
BY
TURNING
ITS
ADJUSTER
END
FULLY
CLOCKWISE
.
THIS
PREVENTS
ACTUATION
OF
THE
TRIP
SHAFT
PADDLE
.
The
trip
device
requires
one
basic
adjustment
—
the
trip
rod
length
.
As
shown
in
Fig
.
11
,
the
clearance
between
the
trip
rod
end
and
the
trip
shaft
paddle
is
gaged
by
a
.
093
"
dia
.
rod
.
To
adjust
,
open
the
breaker
and
restore
the
breaker
mechanism
to
its
7
Courtesy of NationalSwitchgear.com

BUFFER
STUD
ACTUATOR
BRACKET
Flux
shift
trip
device
—
reset
linkage
attachment
1
.
Actuator
2
.
Actuator
arm
3
.
Trip
rod
4
.
Trip
rod
adjuster
end
5
.
Reset
linkage
6
.
Actuator
bracket
7
.
Mounting
base
/
Flux
shift
trip
device
with
operating
linkages
8
Courtesy of NationalSwitchgear.com

CROSSBAR
(
BKR
.
OPEN
)
/
ACTUATOR
BRACKET
BUFFER
STUD
POSITION
O
/
T
?
TRIP
PADDLE
IN
“
MECHANISM
RESET
’’
POSITION
//
/
JAM
<
9
p
NUT
A
(
B
/
/
/
/
/
/
/
.
093
"
DIA
.
TRIP
ROD
IN
“
RESET
POSITION
ROD
i
J
ADJUSTER
END
Fig
.
11
.
Flux
shift
trip
device
adjustments
SIDE
VIEW
1
.
Trip
rod
length
:
Adjust
gap
to
0.093
"
±
0.015
"
using
0.093
"
diam
.
rod
as
shown
.
2
.
Actuator
bracket
:
As
the
crossbar
travels
between
the
breaker
closed
’’
and
“
breaker
open
”
positions
,
the
tang
of
the
actuator
bracket
must
clear
the
buffer
stud
.
If
in
-
sufficient
clearance
exists
,
loosen
it
’
s
two
mounting
screws
and
rotate
the
bracket
clockwise
to
take
up
mounting
hole
slack
.
Retighten
screws
.
(
i
9
Courtesy of NationalSwitchgear.com

a
.
testing
two
poles
of
the
breaker
in
se
-
nes
or
,
b
.
Using
the
Ground
Fault
Defeat
Cable
as
shown
in
Fig
.
16
.
This
special
test
cable
energizes
all
the
primary
windings
of
the
differential
transformer
in
a
self
-
cancell
-
ing
,
series
-
parallel
connection
so
that
its
secondary
output
is
always
zero
.
TROUBLESHOOTING
When
malfunctioning
is
suspected
,
tne
first
step
in
troubleshooting
is
to
examine
the
circuit
breaker
and
its
power
system
for
abnormal
conditions
such
as
:
a
.
Breaker
tripping
in
proper
response
to
over
-
currents
or
incipient
ground
faults
.
b
.
Breaker
remaining
in
a
trip
-
free
state
due
to
mechanical
interference
along
its
trip
shaft
.
c
.
Inadvertent
shunt
trip
activations
.
Test
the
components
of
the
SST
system
using
portable
Test
Set
type
TAK
-
TS
1
(
Fig
.
12
)
.
The
applicable
test
procedures
are
detailed
in
In
-
struction
Book
GEK
-
64454
and
are
summarized
below
.
2
.
WARNING
:
DO
NOT
CHANGE
TAPS
ON
THE
CURRENT
SENSORS
OR
ADJUST
THE
PROGRAMMER
UNIT
SET
KNOBS
WHILE
THE
BREAKER
IS
CARRYING
CURRENT
.
USING
THE
SST
TEST
SET
Once
it
has
been
established
that
the
circuit
breaker
can
be
opened
and
closed
normally
from
the
test
position
,
attention
can
be
directed
to
the
trip
de
-
vice
proper
.
Testing
is
performed
by
either
of
two
methods
:
The
TAK
-
TS
1
Test
Set
is
a
portable
instrument
designed
for
field
-
checking
the
time
-
current
charac
-
teristics
and
pickup
calibration
of
the
SST
’
s
various
trip
elements
.
It
can
verify
the
ability
of
the
Flux
-
Shift
Trip
Device
to
trip
the
breaker
and
,
in
addi
-
tion
,
includes
means
for
continuity
checking
the
phase
sensors
.
1
.
Conduct
high
-
current
,
single
phase
tests
on
the
breaker
using
a
high
current
-
low
voltage
test
set
.
WARNING
:
BEFORE
CONNECTING
THE
TEST
SET
TO
THE
BREAKER
TRIP
DEVICE
SYSTEM
,
ENSURE
THAT
THE
CIRCUIT
BREAKER
IS
COMPLETELY
DISCON
-
NECTED
FROM
ITS
POWER
SOURCE
.
ON
DRAWOUT
EQUIPMENT
,
RACK
THE
BREAKER
TO
ITS
DISCONNECTED
POSI
-
TION
.
VERIFY
THAT
THE
BREAKER
IS
TRIPPED
.
t
NOTE
:
For
these
single
-
phase
tests
,
spe
-
cial
connections
must
be
employed
for
SST
breakers
equipped
with
Ground
Fault
.
Any
single
-
phase
input
to
the
ground
differential
transformer
will
gener
-
ate
an
unwanted
"
ground
fault
”
output
signal
which
will
trip
the
breaker
.
This
can
be
nullified
either
by
:
/
Fig
.
12
.
SST
/
ECS
test
set
,
CAT
.
NO
.
TAK
-
TS
1
10
Courtesy of NationalSwitchgear.com