Westinghouse De-ion DB-15 User manual

I
.
B
.
35
-
225
-
1
C
i
RECEIVING
•
INSTALLATION
•
MAINTENANCE
De
-
ion
®
1
AIR
CIRCUIT
BREAKERS
Types
DB
-
15
and
DB
-
25
600
Volts
A
-
C
250
Volts
D
-
C
Interrupting
Rating
Type
DB
-
25
25
/
000
Amperes
Type
DB
-
15
15
,
000
Amperes
Rating
of
Series
Coils
Type
DB
-
25
(
Amperes
)
40
,
50
,
70
,
90
,
100
,
125
,
150
,
175
,
200
,
225
,
250
,
300
,
350
,
400
,
500
,
600
Type
DB
-
15
(
Amperes
)
15
,
20
,
30
,
40
,
50
,
70
,
90
,
100
,
125
,
150
,
175
,
200
,
225
WESTING
HOUSE
ELECTRIC
CORPORATION
SWITCHGEAR
DIVISION
EAST
PITTSBURGH
,
PA
.
NOVEMBER
,
1954
Printed
la
U
.
S
.
A
.
EAST
PITTSBURGH
PLANT
SUPERSEDES
1.8
.
35
-
225
-
1
B
'
'
i
.
1
<
s
Courtesy of NationalSwitchgear.com

'
I
I
•
=
?
TABLE
OF
CONTENTS
•
"
‘
1
RECEIVING
,
HANDLING
AND
STORING
L
Page
7
Part
One
Inspection
Storing
.
.
.
7
7
INSTALLATION
Pages
8
-
11
Part
Two
Connections
Enclosures
. .
8
8
MAINTENANCE
Pages
12
-
32
Part
Three
Pole
Unit
Contacts
.
Maintenance
of
Contacts
Operating
Mechanism
Closing
Solenoid
Overcurrent
Tripping
Device
Construction
Installation
and
Removal
Time
Current
Classification
Operation
Adjustment
of
Settings
Replacing
Overcurrent
Devices
. . . .
Control
Relay
Shunt
Trip
Attachment
Undervoltage
Trip
Attachment
Undervoltage
Time
Delay
Attachment
Reverse
Current
Trip
Attachment
. .
.
.
Field
Discharge
Switch
Auxiliary
Switch
Alarm
Switch
Attachment
Electric
Lockout
Attachment
Key
Interlock Attachment
Terminal
Block
12
12
12
12
{
12
14
14
14
15
15
21
21
21
23
24
26
26
29
29
30
30
32
32
'
1
Courtesy of NationalSwitchgear.com

I
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35
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225
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1
C
“
DB
”
AIR
CIRCUIT
BREAKERS
LIST
OF
ILLUSTRATIONS
Page
Figure
1
Type
"
DB
"
Air
Circuit
Breaker
—
Exploded
View
2
Ventilated
Enclosures
—
-
Outline
Dimensions
and
Mounting
Details
9
3
DB
-
25
Outline
Dimensions
and
Mounting
Details
4
DB
-
15
Outline
Dimensions
and
Mounting
Details
5
Cross
-
Sectional
View
of
Type
DB
-
25
Circuit
Breaker
6
Overcurrent
Tripping
Device
—
Location
.
6
A
Overcurrent
Tripping
Device
—
Construction
Details
7
Tripping
Characteristics
of
DB
-
15
and
DB
-
25
Overcurrent
Tripping
Devices
with
Long
Time
Delay
and
Instantaneous
Elements
7
A
Tripping
Characteristics
DB
-
15
and
DB
-
25
Dual
Selective
Over
-
current
Tripping
Device
for
Group
and
Tie
Breakers
7
B
Time
-
Current
Characteristics
of
DB
-
25
Circuit
Breakers
Equipped
with
Typical
Overcurrent
Tripping
Devices
for
Motor
Starting
and
Selective
Operation
7
C
Schematic
Diagram
—
Dual
Overcurrents
Series
Tripping
Device
DB
-
15
and
DB
-
25
Load
Circuit
Breakers
7
D
Schematic
Diagram
—
Dual
Overcurrent
Series
Tripping
Device
DB
-
15
and
DB
-
25
Group
or
Tie
Circuit
Breakers
8
Typical
Wiring
Diagrams
—
Type
"
DB
"
Circuit
Breaker
9
Control
Relay
—
Location
,
Adjustment
,
and
Construction
Details
10
Shunt
Trip
Attachment
—
Location
and
Construction
Details
.
.
..
.
..
.
11
Undervoltage
Trip
Attachment
—
Location
and
Construction
Details
.
12
Undervoltage
Time
Delay
Attachment
—
Location
12
A
Undervoltage
Time
Delay
Attachment
—
Construction
Details
13
Reverse
Current
Trip
Attachment
—
Location
13
A
Reverse
Current
Trip
Attachment
—
Construction
Details
14
Field
Discharge
Switch
—
Location
and
Construction
Details
15
Auxiliary
Switch
—
Location
15
A
Auxiliary
Switch
—
Construction
Details
16
Alarm
Switch
Attachment
—
Location
16
A
Alarm
Switch
Attachment
—
Construction
Details
17
Electric
Lockout
Attachment
—
Location
and
Construction
Details
.
.
.
18
Key
Interlock
Attachment
—
Location
and
Construction
Details
19
Terminal
Block
Attachment
—
Construction
Details
6
10
11
13
14
.
15
16
16
18
19
20
\
22
23
24
25
26
26
27
27
28
29
29
i
30
30
31
32
32
3
Courtesy of NationalSwitchgear.com

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-
r
4
Courtesy of NationalSwitchgear.com

I
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C
<
4
DB
”
AIR
CIRCUIT
BREAKERS
Westinghouse
TYPE
"
DB
"
AIR
CIRCUIT
BREAKER
Type
"
DB
"
air
circuit
breaker
is
designed
to
give
continuous
and
reliable
service
as
the
protective
link
between
the
power
source
and associated
pro
-
ductive
equipment
.
This
breaker
is
built
to
operate
with
a
minimum
of
main
-
tenance
,
while
at
the
same
time its
simplified
construction
permits
maximum
accessibility
for
inspection
and
adjustment
when
required
.
The
ease
with
which
attachments
may
be
added
or
removed
is
an
outstanding
feature
of
the
"
DB
"
design
.
For
the
greatest
measure
of
safety
to
operating
personnel
and
also
to
min
-
imize
maintenance
requirements
,
the
breaker should
be
mounted
in
an
enclosure
suitable
to
local
operating
conditions
.
A
selection
of
standard
enclosures
is
available
for
various
applications
.
Important
:
To
assure
proper
functioning
,
inspect
each breaker
at
reg
-
ular
intervals
in
accordance
with
a
systematic
maintenance
schedule
.
The
frequency
and
character
of
the
inspections
will
for
the
most
part
be
determined
by
the
severity
of
the
duty
performed
.
The
minimum
requirements
,
however
,
should
consist
of
a
light
monthly
inspection
,
with
a
thorough
inspection
semi
-
annually
.
Occasional
checks
on
cali
-
bration
as
well
as on
coordination
and
freedom of
all
moving
parts
,
must
be
included
in
the
maintenance
schedule
.
Consult
Westinghouse
engineering
and
service
personnel
for
recommendations
pertaining
to
special
operating
or
maintenance
conditions
.
5
Courtesy of NationalSwitchgear.com

N
.
T
*
-
FIG
.
1
.
Type
“
DB
”
Air
Circuit
Breaker
—
Exploded
View
6
Courtesy of NationalSwitchgear.com

!
T
I
.
B
.
35
-
225
-
1
C
“
DB
”
AIR
CIRCUIT
BREAKERS
PART
ONE
•
•
\
RECEIVING
,
HANDLING
AND
STORING
a
.
Observe
whether
all
parts
are
in
proper
alignment
and
move
freely
.
Type
"
DB
”
air
circuit
breakers
,
with
all
attach
-
ments
mounted
in
place
,
are
shipped
in
wooden
crates
or
cardboard
containers
.
Important
:
To
avoid
damage
to
the
break
-
ers
,
do
not
use
hooks
in
handling
.
Net
weights
of
Types
DB
-
15
and
DB
-
25
fixed
breakers
are
given
in
Table
No
.
1
below
.
Add
15
lbs
.
for
drawout
breakers
.
i
b
.
Make
certain
that
the
studs
have
not
been
forced
out
of
alignment
.
c
.
Be
sure
that
the
contacts
are
clean
and
properly
aligned
.
For
a
description
of
contact
align
-
ment
,
refer
to
"
Contacts
”
,
page
12
.
T
3
.
If
the
contacts
are
in
alignment
and
all
parts
move
freely
,
continue
the
clockwise
rotation
until
the
breaker
is
latched
.
Table
No
.
I
.
NET
WEIGHTS
DB
-
15
DB
-
25
TYPE
4
.
Return
the
manual
operating
handle
to
the
neutral
position
,
then
rotate
counterclockwise
to
trip
the
breaker
.
3
-
Pole
2
-
Pole
2
-
Pole
3
-
Pole
60
lbs
.
75
lbs
.
70
lbs
.
85
lbs
.
80
lbs
.
100
lbs
.
90
lbs
.
110
lbs
.
Manual
Electric
a
.
The
toggle
linkage
should
collapse
and
the
moving
contact
assembly
move
freely
to
the
full
open
position
.
This
should
be
followed
immediate
-
ly
by
complete
resetting
of
the
links
in
the
toggle
mechanism
as
the
handle
is
returned
to
the
neutral
position
.
Immediately
upon
receipt
,
examine
the
shipment
for
any
loss
or
damage
incurred
during
transit
.
If
injury
or
rough
handling
is
evident
,
file
a
damage
claim
at
once
with
the
transportation
company
and
notify
the
nearest
Westinghouse
Sales
Office
.
When
unpacking
,
be
sure
that
no
loose
parts
are
missing
or
left
in
the
packing
material
.
Report
all
shortages
at
once
.
Blow
out
any
dust
or
particles
of
packing
material
that
may
have
accumulated
on
the
circuit
breaker
parts
.
Remove
tape
from
top
of
arc
chutes
.
b
.
The
links
must
always
be
free
to
move
without
friction
or
binding
.
S
.
Check
the
attachments
for
operation
in
accord
-
ance
with
the
appropriate
instructions
as
given
under
"
Maintenance
”
,
Part
Three
of
this
book
.
6
.
The
latchplate
felt
and
roller
lever
of
the
oper
-
ating
mechanism
should
be
lubricated
approxi
-
mately
every
10
,
000
operations
.
Molybdenum
disul
-
fide
mixed
with
oil
(
Westinghouse
oil
M
8577
-
11
)
is
recommended
.
INSPECTION
The
"
DB
”
breaker
assembly
consists
of
a
coor
-
dinated
group
of
sub
-
assemblies
mounted
on
a
steel
supporting
panel
.
(
See
Fig
.
1
)
.
The
complete
break
-
er
assembly
is
to
be
mounted
with
the
steel
panel
in
a
vertical
position
.
All
inspections
for
proper
operation
should
,
therefore
,
be
made
with
the
break
-
er
in
this
position
.
Final
inspection
should
prefer
-
ably
be
made
with
the
breaker
in
its
permanent
mounting
.
Inspect
the
breaker
as
follows
:
1
.
Raise
and
lower
the
trip
bar
by
hand
to
make
sure
that
it
does
not
bind
.
2
.
Rotate
the
manual
operating
handle
slowly
in
a
clockwise
direction
to
move
the
contacts
toward
the
closed
position
.
STORING
If
circuit
breakers
are
not
to
be
installed
in
their
permanent
location
at
once
,
they
should
be
care
-
fully
inspected
for
loose
or
damaged
parts
and
then
stored
in
a
clean
dry
place
in
an
upright
position
to
avoid
damage
to
the
circuit
breaker
parts
.
A
covering
of
paper
will
prevent
dust
from
settling
on
the
circuit
breaker
parts
and
is
preferred
to
packing
or
other
materials
that
are
apt
to
absorb
moisture
.
7
Courtesy of NationalSwitchgear.com

PART
TWO
r
_
»
^
INSTALLATION
that
the
mounting
dimensions
differ
and
should
be
obtained
from
the
appropriate
outline
drawing
.
Type
"
DB
"
circuit
breakers
are
furnished
as
com
-
plete
unit
assemblies
and
the
installation
consists
(
1
)
bolting
them
to
the
supporting
framework
or
structure
;
(
2
)
connecting
the
current
-
carrying
cables
or
bus
bars
;
and
(
3
)
completing
any
second
-
ary
control
wiring
that
may
be
necessary
.
Caution
:
During
installation
,
the
circuit
breaker
should
be
in
the
open
position
.
Be
sure
to
de
-
energize
the
load
and
control
leads
to
be
connected
,
and
also
the
section
of
the
switchboard
where
the
installation
is
being
made
.
Mounting
dimensions
and
details
of
front
enclo
-
sure
cutouts
are
shown
in
Figs
.
2
,
3
and
4
,
To
prevent
distortion
of
the
breaker
panel
,
the
supporting
structure
should
be
checked
for
align
-
ment
.
of
:
The
following
procedure
applies
to
all
enclosures
:
l m
Connect
the
entrance
cables
first
.
Whenever
possible
,
the
power
cables
should
be
connected
to
the
top
terminals
to
remove
voltage
from
the
over
-
current
attachments
when
the
breaker
is
open
.
The
cables
can
be
connected
to
the
nearest
terminal
,
or
to
the
opposite
terminal
as
shown
in
Fig
.
2
.
Tin
the
ends
of
the
cable
to
prevent
the
formation
of
copper
oxide
.
Tighten
the
clamp
bolt
securely
and
lock
with
the
lock
nut
.
2
.
Control
wires
should
run
along
the
left
side
of
the
enclosure
below
the
rail
.
Connect
to
the
terminal
block
or
auxiliary
switch
by
running
be
-
tween
the
breaker
platform
and
the
rail
in
front
of
the
wheel
,
after
the
breaker
is
bolted
in
place
.
When
removing
the
breaker
,
disconnect
the
control
wiring
from
the
terminal
block
or
auxiliary
switch
and
lay
in
the
bottom
of
the
enclosure
,
out
of
the
way
of
the
breaker
.
CONNECTIONS
Typical
circuit
breaker
wiring
diagrams
are
shown
in
Fig
.
8
.
The
connecting
cables
or
bus
bars
should
have
adequate
current
-
carrying
capacity
,
otherwise
,
heat
will
be
conducted
to
the
circuit
breaker
resulting
in
possible
excessive
temperature
rise
.
Connecting
cables
or
bus
bars
must
be
sup
-
ported
so
that
the
circuit
breaker
studs
will
not
be
subjected
to
unnecessary
stresses
.
The
circuit
breaker
studs
and
all
connections
should
be
clean
,
smooth
,
and
free
from
burrs
to
assure
full
contact
area
.
They
should
be
firmly
clamped
or
bolted
in
place
to
prevent
excessive
heating
.
3
.
Roll
the
breaker
into
the
enclosure
until
the
four
mounting
bolts
engage
the
mounting
brackets
.
The
mounting
bolts
are
used
as
jacks
to
pry
the
finger
clusters
into
engagement
with
the
terminals
,
and
consequently
each
bolt
should
be
tightened
*
4
inch
in
succession
until
the
breaker
panel
is
tight
against
the
mounting
brackets
.
The
same
procedure
should
be
followed
in
removing
the
breaker
,
i
.
e
.
,
remove
each
bolt
%
inch
in
succession
until
they
drop
free
.
4
-
Always
rotate
the
operating
handle
to
the
tripped
position
before
removing
the
front
cover
.
A
trip
rod
(
not
shown
in
Fig
.
2
)
holds
the
breaker
trip
free
when
the
front
cover
is
off
.
When
operating
the
breaker
in
the
test
position
(
front
wheels
engag
-
ing
the
slot
in
the
rail
)
,
it
is
unnecessary
to
hold
this
rod
in
manually
to
secure
closure
of
the
breaker
.
When
fastening
the
cover
in
place
,
draw
the
four
cover
bolts
down
firmly
.
ENCLOSURES
The
terminal
panel
and
breaker
arrangement
shown
in
Fig
.
2
apply
specifically
to
ventilated
enclosures
.
The
same
arrangement
is
used
for
all
other
enclosures
(
weatherproof
,
subway
,
explosion
-
proof
,
dust
tight
and
semi
-
dust
tight
)
except
8
Courtesy of NationalSwitchgear.com

I
.
B
.
35
-
225
-
1
C
INSTALLATION
“
DB
”
AIR
CIRCUIT
BREAKERS
•
S
'
4
»
T
i
FIG
.
2
.
Ventilated
Enclosures
—
Outline
Dimensions
and
Mounting
Details
9
Courtesy of NationalSwitchgear.com

INSTALLATION
,
*
s
Dl
A
M
)
FOR
KEY
INTERLOCK
ONLY
O
O
BKR
.
18
U K
5
f
3
?
BKR
.
16
*
[
=
1
=
1
72
rR
.
8
A
a
4
i
HANDLE
t
*
T
*
3
13
!
6
3
-
3
«
r
a
±
o
VIEW
"
B
"
VIEW
"
A
"
VIEW
"
C
"
CUTOUT
IN
DEAD
FRONT
DOOR
OR
COVER
FRONT
VIEW
OF
STUD
LOCATIONS
,
CUTOUTS
DRILLING
FOR
MOUNT
-
ING
3
-
POLE
BREAKER
WITH
2
OR
3
OVERCURRENT
TRIPS
,
OR
2
-
POLE
BREAKER
WITHOUT
REVERSE
CURRENT
TRI
P
FRONT
VIEW
OF
STUD
LOCATION
,
CUTOUT
S
DRILLING
FOR
MOUNT
-
ING
2
-
POLE
BREAKER
WITH
2
OVERCURRENT
TRIPS
S
REVERSE
CURRENT
TRI
P
.
.
(
FOR
DIMS
.
SEE
VIEW
A
)
1
LIVE
PARTS
OR
COMBUSTIBLE
MATERIAL
MUST
NOT
BE
LOCATED
IN
THIS
AREA
,
UNLESS
GAS
DEFLECTING
BARRIERS
ARE
PROVIDED
HERE
.
3
II
4
7
17
5
~
32
0
I
A
.
*
8
33
6
4
O
BKR
.
I
o
2
'
t
8
I
8
I
)
8
I
n
2
r
i
r
o
I
CD
STUD
Is
8
9
18
^
16
)
A
20
HANDLE
3
16
7
-
4
O
P
*
STUD
L
9
5
I
I
'
DIA
3
TX
3
x
~
3
7
T
16
16
2
2
(
4
)
I
6
2
7
I
13
2
X
ll
-
s
*
0
4
VIEW
'
D
"
3
'
POLE
BREAKER
WITHOUT
REVERSE
CURRENT
TRIP
,
OR
2
-
POLE
BREAKER
WITH
OR
WITHOUT
REVERSE
CURRENT
TRIP
VIEW
'
E
"
BOUNDARY
SURFACES
OF
THE
CIRCUIT
BREAKER
ARE
TO
BE
CONSIDERED
GROUND
POTENTIAL
.
FIG
.
3
.
DB
-
25
Outline
Dimensions
and
Mounting
Details
Courtesy of NationalSwitchgear.com

I
.
B
.
35
-
225
-
1
C
INSTALLATION
,
“
DB
”
AIR
CIRCUIT
BREAKERS
FIG
,
4
.
DB
-
15
Outline
Dimensions and
Mounting
Details
11
Courtesy of NationalSwitchgear.com

I
I
PART
THREE
MAINTENANCE
POLE
UNIT
Maintenance
of
Contacts
.
Rough
or
high
spots
should
be
removed
with
a
file
or
sandpaper
.
To
replace
the
arcing
contacts
,
open
the
breaker
,
remove
the
arc
chutes and then
the
stationary
arc
-
ing
contacts
.
Close
the breaker and
remove
the
moving arcing
contacts
.
The
new
contacts
can
then
be added
in
the
reverse
order
.
Caution
:
All
power
should
be
removed
when
changing
,
maintaining
or
adjusting
contacts
.
Each
pole
unit is
mounted
on
a
separate
molded
base
through
which
the breaker
studs
pass
.
(
See
Fig
,
6
)
.
The
molded
bases
are
attached
to
the
steel
mounting
panel
and
provide
insulation
for
the
break
-
er
studs
.
The
upper
stud
and
contact
are
attached
to
the
molded
base
by
one
bolt
.
The
moving
contact
is
pivoted
on
the molded base and attached
to
the
cross
bar
through insulating
links
.
The
series
coil
and
lower
stud
are
fastened
to
the
molded
base
by
three
bolts
.
Contacts
.
(
See
Fig
.
6
)
.
The
DB
-
25
arcing
con
-
tacts
should
touch first
on
closing
,
open
last
on
opening
,
and
have
approximately
a
%
2
-
inch
gap
when
the breaker
is
completely
closed
.
This
gap
is
adjusted
by
removing
the
cross
bar and
screwing
the
insulating
link
in
or
out
on
the
stud
.
Be
sure
to
tighten
the lock
nuts
after
each
adjustment
.
The
DB
-
15
contacts
are
adjusted
to
obtain
%
2
to
l
/
a
inch
gap
between the
armature
plate
and the
steel
link
.
As
the
contacts
burn
away
it
will
be
necessary
to
adjust
as
described
above
for
the
DB
-
25
.
Do
not
over
-
adjust
as
this will
cause
the
opening
spring
to
compress
to
the solid
position
and thus
increase
the
closing
effort
.
Check
for
over
-
adjust
-
ment
by
manually
pulling
the
moving
contact
away
from
the
stationary
contact
,
with the breaker
in
the
closed
position
.
It
should
be
possible
to
obtain
at
least
%
4
-
inch
gap
between
contacts
.
OPERATING
MECHANISM
The
operating
mechanism
(
see
Fig
.
6
)
is
non
-
ad
justable
and
consists
of
a
series
of
stainless
steel
links
designed
to
secure
low
closing
and
tripping
forces
.
To
check
for
friction
,
raise
the
trip
bar and
slowly
rotate
the manual
operating
handle
in
close
and
trip
direction
.
The
linkage
should
follow the
handle without
sticking
.
The
tripping
load should
not
exceed
38
ounces
measured
at
the
trip
bar
.
CLOSING SOLENOID
The
closing
solenoid
(
see
Fig
.
6
)
is
non
-
adjustable
.
It
is
designed
for
intermittent
duty
only
.
Check
for
loose bolts
.
The
minimum
permissible
control
voltages
at
the
terminal
of
the
closing
coil
,
and the
closing
currents
at
nominal
voltage
are
listed
in
Table
No
.
2
below
.
m
Table
No
.
2
.
CLOSING SOLENOID CONTROL
VOLTAGES
AND
CLOSING
CURRENTS
MINIMUM
VOLTAGE
AT
COIL TERMINALS
CLOSING
CURRENT
IN
AMPERES
AT
NOMINAL
VOLTAGE
FOR
3
-
POLE BREAKERS
NOMINAL
VOLTAGE
0
DB
-
25
Close
DB
-
15
Close
DB
-
15
and
DB
-
25
Close
Trip
Trip
Special
Standard
18
12
V
,
D
-
C
24
V
,
D
-
C
48
V
,
D
-
C
125
V
,
D
-
C
250
V
,
D
-
C
115
V
,
60
Cy
230
V
,
60
Cy
460
V
,
60
Cy
7
14
9.5
28
5
90 70
20 25
30
2
180
140 10
12
15
1
1
95
190 190
30 35
49
.
5
380
380 15
20
24
.
2
*
NOTE
:
For
A
-
C
closing
use
3
-
kva
source
or
larger
.
0
Standard
close coils
used when
overcurrent
tripping
devices
have
instantaneous
trip
.
Special
close coils used when
overcurrent
tripping
devices have short
delay
feature
.
12
Courtesy of NationalSwitchgear.com

/
\
I
.
B
.
35
-
225
-
JC
MAINTENANCE
^
\
“
DB
”
AIR
CIRCUIT
BREAKERS
V
W
*
\
m
FIG
.
6
.
Cross
-
Sectional
View
of
Type
DB
-
25
Circuit
Breaker
Courtesy of NationalSwitchgear.com

MAINTENANCE
Construction
.
The
overcurrent
tripping
device
is
of
the
air
delayed
type
with
all
elements
adjust
-
able
.
The
adjustment
knobs
or
parts
likely
to
be
touched
while
making
adj
ustments
of
time
or
pickup
current
are
electrically
insulated
.
Fig
.
6
A
shows
a
typical
overcurrent
tripping
device
ready
for
mounting
on
a
breaker
pole
unit
.
Installation
and
Removal
.
To
install
an
over
-
current
tripping
device
,
first
make
sure
the
lower
end
of
the
flexible
conductor
is
in
the
recessed
pocket
of
the
molded
base
directly
above
the
lower
breaker
stud
.
Then
place
the
trip
unit
so
that
the
top
terminal
of
the
tripping
device
is
over
the
flexible
conductor
and
the
lower
tripping
device
terminal
is
over
the
lower
breaker
stud
.
Insert
the
three
bolts
into
the
rear
of
the
base
and
thread
them
tightly
into
the
terminals
and
molded
base
of
the
tripping
device
.
The
mounting
bolt
sizes
are
shown
in
Table
No
.
3
.
Table
No
.
3
.
MOUNTING
BOLT
SIZES
DB
-
25
BOLT
DB
-
15
Thread
Length
I
/
2
-
13
X
2
&
*
54
-
13
*
194
'
%
-
16
x
1
%
"
Thread
Length
!
/
2
-
13
x
li
/
2
"
/
2
-
13
X
V
3
/
6
-
16
X
r
Top
Center
Bottom
{
FIG
.
6
.
Overcurrent
Tripping
Device
—
Location
Use
one
lock
washer
only
,
under
the
head
of
each
of
these
bolts
.
Care
should
be
taken
to
make
sure
that
bolts
longer
than
called
for
above
are
not
used
,
otherwise
,
the
ends
of
the
bolts
may
jam
against
the
coil
and
short
circuit
some
of
the
turns
.
To
adjust
the
trip
nut
for
proper
tripping
,
first
insert
valve
lever
tool
"
B
"
or
a
Vie
diameter
rod
,
in
the
long
delay
calibration
bracket
(
left
slot
)
and
raise
the
valve
lever
to
its
maximum
position
.
This
removes
all
of
the
time
delay
and
permits
the
arma
-
ture
to
operate
easily
.
Then
insert
the
push
rod
"
A
"
Fig
.
6
A
in
the
top
slot
of
the
calibration
bracket
and
push
the
armature
solidly
against
the
yoke
;
close
the
breaker
and
adjust
the
trip
nut
to
barely
trip
the
breaker
.
Several
trials
may
be
necessary
.
Next
turn
the
trip
nut
upwards
three
quarters
turn
to
provide
overtravel
.
This
completes
the
adjustment
as
the
trip
nut
is
self
locking
.
To
remove
an
overcurrent
tripping
device
from
the
breaker
,
remove
the
three
bolts
,
which
hold
the
tripping
device
to
the
breaker
base
.
Before
re
-
moving
the
last
bolt
,
hold
the
tripping
device
to
prevent
it
from
falling
.
OVERCURRENT
TRIPPING
DEVICE
The
overcurrent
tripping
devices
of
the
various
ampere
ratings
are
of
the
same
general
construction
and
size
.
They
can
be
applied
to
the
DB
-
15
circuit
breaker
in
ratings
of
15
to
225
amperes
and
to
the
DB
-
25
circuit
breaker
in
ratings
of
40
to
600
amperes
.
The
overcurrent
tripping
device
can
easily
be
removed
from
the
breaker
and
replaced
with
another
unit
of
different
rating
without
affecting
the
cali
-
bration
.
w
The
overcurrent
tripping
device
,
normally
fur
-
nished
for
each
pole
of
the
circuit
breaker
,
is
de
-
signed
for
service
on
motor
or
general
purpose
feeder
circuits
or
for
service
on
systems
where
selective
overcurrent
tripping
is
desired
.
Figures
7
A
and
7
B
shows
time
-
current
characteristics
of
DB
-
15
and
DB
-
25
,
circuit
breakers
equipped
with
typical
overcurrent
tripping
devices
,
for
selective
tripping
.
1
14
Courtesy of NationalSwitchgear.com

I
.
B
.
35
-
225
-
1
C
MAINTENANCE
“
DB
”
AIR
CIRCUIT
BREAKERS
2
—
Dual
Selective
Overcurrent
Tripping
Device
for
Group
or
Tie
Breakers
This device
has
an
adjustable
long
delay
and
adjustable
short
delay
element
and
is
suitable
for
service
on
systems
where
selective
overcurrent
trip
-
ping
is
desired
.
Curves
7
A
and
7
B
show the
time
-
current
characteristics
of
these devices
.
Time
-
Current
Classification
.
The
overcur
-
rent
tripping
device
can
be
furnished
with
either
a
short
delay
or
an
instantaneous
element
,
or
in
any
combination
of
two
of
the
three
tripping
ele
-
ments
,
namely long
delay
,
short
delay
and
instan
-
taneous
elements
.
The
most
popular
overcurrent
tripping
devices
are
listed below
:
1
—
Dual
Overcurrent
Tripping
Device
for
Load
Breakers
This device has
an
adjustable
long
delay
and
an
adjustable
instantaneous
element
and
is
suitable
for
service
on
motor
or
general
purpose
feeder
circuits
.
A
characteristic
curve
is
shown
in
Fig
.
7
.
Operation
1
—
Dual
Overcurrent
Tripping
Device
for
Load
Breakers
,
Fig
.
7
C
Overload
currents
above
the
setting
of
the
long
delay
pick
-
up
adjustment
(
M
)
forces
the
armature
w
FIG
.
6
A
.
Overcurrent
Tripping
Devia
Construction
Details
15
Courtesy of NationalSwitchgear.com

r
MAINTENANCE
«
1
4
1
FIG
.
7
.
Typical
Tripping
Characteristics
of
DB
-
15
and
DB
-
25
Overcurrent
Tripping
Devices
with
Long
Time
Delay
and
Instantaneous
Elements
16
Courtesy of NationalSwitchgear.com

I
)
V
.
B
.
35
-
225
-
C
MAINTENANCE
“
DB
”
AIR
CIRCUIT
BREAKERS
I
000
*
Wr
500
LONG
DELAY
PICKUP
SETTINGS
.
ADJUSTABLE
WITH
CALIBRATED
MARKS
A T
8 0
,
100.120
,
140
&
160
PERCENT
O F
COIL
RATING
.
\
\
\
\
\
TOTAL
CLEARING
TIME
I
\
1
00
\
*
\
LONG
DELAY
SETTINGS
.
ADJUSTABLE
W l
T H
CAL
I
-
BRATED
MARKS
A T
3 0
&
2
2 0
SECONDS
.
\
r
v
5 0
T
N
X
s
\
\
\
s
\
\
SHORT
DELAY
PICKUP
SETTINGS
.
ADJUSTABLE
WITH
CALIBRATED
MARKS
A T
500.750
&
1000
PER
.
CENT
O F
COIL
RATING
.
\
1
0
\
/
\
to
\
RESETTABLE
DELAY
•
—
-
/
Q
/
\
N
i
/
Z
Z
\
o
5
\
y
/
O
<
U J
/
/
*
t o
/
/
s
/
/
\
z
SHORT
DELAY
SETTINGS
-
ADJUSTABLE
WITH
CALI
.
BRATED
MARKS
A T
6.14
.
f t
3 0
CYCLES
.
„
COIL
RATINGS
(
AMPS
.
)
/
/
\
x
LLJ
/
1
\
INTERMED
.
BAND
MAX
.
BAND
MIN
.
BAND
/
\
/
*
—
A
1
/
/
\
DB
15
DB
25
DB
15
DB
25
DB
15
DB
25
/
\
\
3 0
CYCLES
225
600
225
600
225
200
500
200
500
200
175
400
175
400
175
150
350
150
350
150
125
300
125
300
100
250
600
.
5
Z
500
MAX
I
MUM
BAN
D
400
350
Z
1 4
CYCLES
300
.
v
v
\
\
\
\
'
\
\
\
\
\
N
\
\
\
x
\
x
V
\
\
\
\
N
\\
X
250
250
I
NTERMEDI
ATE
BAND
225
225
200
200
|
-
6
CYCLES
.
1
/
z
%
zzzzzzzz
175
/
/
MINI
MUM
BAN
D
.
0 5
.
0 1
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
CURRENT
I N
PERCENT
O F
COIL
RATING
FIG
.
7
A
.
Typical
Tripping
Characteristics
DB
-
15
and
DB
-
25
Dual
Selective
Overcurrent
Tripping
Device
£
or
Group
and
Tie
Breakers
.
17
Courtesy of NationalSwitchgear.com

MAINTENANCE
I
i
1
»
l l
Typical
Time
-
current
Characteristics
o
£
DB
-
25
Circuit
Breakers
Equipped
with
Typical
Overcurrent
Tripping
Devices
for
Motor
Starting
and
Selective
Operation
FIG
.
7
B
.
18
Courtesy of NationalSwitchgear.com

LB
.
35
-
225
-
1
C
MAINTENANCE
,
<
4
DB
”
AIR
CIRCUIT
BREAKERS
1
i
i
i
FIG
.
7
C
.
Schematic
Diagram
—
Dual
Overcurrent
Series
Tripping
Device
DB
-
15
and
DB
-
25
Load
Circuit
Breakers
19
Courtesy of NationalSwitchgear.com

MAINTENANCE
.
;
I
\
r
.
l
A
FIG
.
7
D
.
Schematic
Diagram
-
—
Dual
Selective
Overcurrent
Series
Tripping
Device
DB
-
15
and
DB
-
25
Group
or
Tie
Circuit
Breakers
i
i
!
Courtesy of NationalSwitchgear.com