ABB 5HK Series User Manual

IB
6.2
.
1.7
D
Page
8
ASEA
BROWN BOVERI
center
pole
are
not
fully
compressed
no
readjustments
need be
made
.
When
this condition
exists
,
the
center
pole
parts
before
the
outer
poles
on
opening
.
5
.
Open
breaker
,
recharge closing springs
,
remove
slow
-
close bracket
,
fast
close
the
breaker
,
recheck
adjustments
for
7
/
64
"
to
3
/
16
”
,
“
A
”
dimension
.
NOTE
:
Fast
-
closing
the
circuit
breaker
may
result
in
a
slight
increase
in
contact
pressure
over
slow
-
closing
.
6
.
Tighten
the
locking
bolt
(
2
)
on
each
adjusting
stud
(
3
)
to
lock
the
contact
pressure
adjustment
stud
in
place
.
7
.
The
arc
chutes
can
now
be
replaced
,
and the
interphase
barrier
assembly
can
now
be reinstalled
.
8
.
Return the
racking
screwto
its
original
position
by
turning
it
counterclockwise
approximately
two to
three
turns
until
it
stops
.
9
.
The circuit breaker
can
now
be
replaced
in
its
compart
-
ment
and
returned
to
service
.
The
following
table lists the millivolt
drop
and
resistance
values
for
the
circuit
breakers
,
when
manufactured
,
cov
-
ered
by
this instruction book
,
from
terminal
,
exclusive
of
the
primary
disconnects
.
Maximum
Micro
-
Ohms
Maximum
MV
Drop
*
Circuit
Breaker
5
HK
75
,
5
HK
150
,
5
HK
250
5
HK
350
,
1200
Ampere
8
40
5
HK
150
,
5
HK
250
,
5
HK
350
2000
Ampere
7
35
5
HK
350
,
3000
Ampere
4
20
5.3
CONTACT
AND
INSULATION
CLEANING
All
dirt
,
soot
or
grease
should be removed
from
circuit
breaker
contacts
and
surface of
entire
current
-
carrying
structure
,
as
well
as
ail
insulation
surfaces
,
with
a
cloth
saturated
with
an
oil
-
free
OSHA
-
approved
solvent
.
Clean
-
ing
of
insulation is
important
because
soot
and dirt
can
accumulate
and
,
with
moisture
,
place
the circuit breaker
in
jeopardy
,
dielectrically
.
A
degree
of
burning
and
pitting
of
circuit breaker
arcing
contacts
is
to
be
expected
from
normal
operation
;
also
,
on
highly
inductive
or
capacitative
circuits and
after
major
interruptions
,
some
pitting
may
occur on
main
contacts
.
A
moderate
amount
of
pitting
will
not
interfere
with
operation
of
the
contacts
.
When
necessary
to
dress the
contacts
,
cover
the
puffer
nozzle
(
5
,
Figure
1
)
with
a
cloth
,
then
follow
the
contour
of
the
contacts
with
a
fine file
.
Do
not
attempt
to
eliminate
pitting
entirely
.
Afterthis
maintenance
,
contact
pressure
(
paragraph
5.2
)
;
and
millivolt
drop
(
paraqraph
5.4
)
should
be
checked
.
NOTE
:
Replacement
of
contacts
is
required
when
:
after
repeated
dressing
of
any
contacts
,
less than
50
%
of
the
original
contact
material thickness is
left
;
*
the
tips
of
the
stationary
arcing
contacts
have been eroded
away
;
any
contact
has been
broken
or
cracked
.
*
On
5
HK
350
,
3000
the
arcing
contct
can
be inverted
when
working
surface
is reduced
to
less
than
50
%
.
*
Millivolt
drop
with
200
amperes
flowing
.
Breakers
operating
with
normal
loading
will
require
no
maintenance
if
the millivolt
drop
does
not
exceed
150
%
of
the
listed
values
.
If
the
millivolt
drop
does
exceed
150
%
of
the
above
values
,
the
main and
arcing
contacts
should be
dressed
with
a
fine
file
,
cleaned
and
adjusted
for
proper
contact
pressure
and
then
rechecked
.
If
the values
are
still
in
excess
of
the
150
%
value
,
the
bridge
pivot
pressure
should
be
readjusted
as
outlined
in
Paragraph
5.6
.
NOTE
:
For
optimum
performance
of
the
circuit
breakers
during
periods
of
increased
loading
,
it
is
recommended
that
the
listed
values be
met
.
After
all
above
steps
have been
taken and the millivolt
drop
is
still
excessive
,
contact
the
nearest
district
office for
recommendations
.
)
5.5
PUFFERS
(
3
,
Figure
1
)
CAUTION CAUTION
CAUTION CAUTION
FOR
SAFETY
KEEP
CLEAR
OF
ALL
MOVING
PARTS
.
The
performance
of
the
puffers
should be
checked
during
a
normal maintenance interval
.
Each
puffer
should
provide
a
moderate
blast
of
air
at
breaker
contacts
,
on
opening
of
thecircuit
breaker
.
This
can
be detected
by holding
a
piece
of
paper
approximately
8
-
1
/
2
"
x
11
"
over
the
top
of
the
contacts
and
opening
the circuit breaker
.
All
three
poles
must
have
puffing
action
or
the circuit breaker
must not
be
placed
in
service
.
5.4
DC
MILLIVOLT DROP
TEST
During
normal
maintenance
periods
the condition
of
the
circuit breaker
can
easily
be
determined
by
performing
a
millivolt
drop
test
.
This
test
shou Id
be
performed
regardless
of
whether the
circuit
breaker had
interrupted
low
or
high
currents
or
has
minimum
operations
.
Courtesy of NationalSwitchgear.com

ABB 5HK Series Specifications

General

Brand	ABB
Model	5HK Series
Category	Circuit breakers
Language	English