Westinghouse DB-75 User manual

Instructions
for
Types
DB
-
75
,
DB
-
100
and
DBF
-
40
Air
Circuit
Breakers
600
volts
A
-
C
250
Volts
D
-
C
Continuous
Current
Rating
DB
-
75
DB
-
100
4
,
000
Amperes
5
,
000
Amperes
/
D
-
C
6
,
000
Amperes
{
Only
2
,
000
Amperes
2
,
500
Amperes
,
3
,
000
Amperes
Westinghouse
Electric
Corporation
Switchgear
Division
,
East
Pittsburgh
,
Pa
.
I
.
B
.
33
-
850
-
4
&
5
D
,
Effective
November
,
1966
.
Supersedes
I
.
B
.
33
-
850
-
4
&
5
C
,
May
,
1962
.
Courtesy of NationalSwitchgear.com

.
v
’
i
TABLE
OF
CONTENTS
RECEIVING
,
HANDLING
AND
STORING
Page
7
Part
One
7
Inspection
Storing
..
.
7
INSTALLATION
Pages
8
-
11
Past
Two
8
Connections
Enclosures
.
.
8
MAINTENANCE
Pages
12
-
24
Part
Three
14
Pole
Unit
Contacts
Maintenance
of
Contacts
.
Operating
Mechanism
Closing
Solenoid
.
Overcurrent
Tripping
Device
Description
.
Construction
Installation
and Removal
Adjustment
of
Trip
Screw
Operation
Standard
Overcurrent
Tripping
Device
Selective
Overcurrent
Tripping
Device
Instantaneous
Overcurrent
Tripping
Device
(
Single
Element
)
Time
-
Current
Characteristics
Calibration
^
Maintenance
X
Control
Relay
Inspection
Maintenance
Shunt
Trip
Attachment
Inspection
Maintenance
Undervoltage
Trip
Attachment
Undervoltage
Time
Delay
Attachment
Inspection
Maintenance
.
..
.
.
Auxiliary
Switch
Inspection
Maintenance
14
14
i
.
<
14
17
k
18
i
-
.
-
18
18
18
f
19
20
20
21
22
22
23
23
24
24
24
24
24
24
24
26
26
26
26
26
26
(
)
2
Courtesy of NationalSwitchgear.com

TABLE
Part
Three
MAINTENANCE
(
Continued
)
Pages
24
-
30
Alarm
Switch
Attachment
.
Inspection
Maintenance
Electric Lockout
Attachment
.
Inspection
Maintenance
Key
Lock
Attachment
,
Inspection
Maintenance
Key
Interlock
Attachment
Inspection
Maintenance
Rectifier
Unit
for
A
-
C
Undervoltage
and
A
-
C
Electric Lockout Attachments
Inspection
.
Maintenance
Reverse
Current
Trip
Attachment
Inspection
Maintenance
Field
Discharge
Switch
Recommended
Spare
Parts
26
26
29
29
29
29
29
29
30
30
30
30
30
30
30
30
30
31
•
S
'
33
V
34
v
.
(
T
1
3
Courtesy of NationalSwitchgear.com

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^
LIST
OF
ILLUSTRATIONS
Page
Figure
1
DB
-
75
Outline
and
Mounting
Dimensions
1
A
DB
-
100
Outline
and
Mounting
Dimensions
IB
DBF
-
40
Outline
and
Mounting
Dimensions
1
C
DB
-
75
Outline
and
Mounting
Dimensions
2
Typical
Wiring
Diagrams
3
Cross
-
Sectional
View
of
DB
-
75
and
DB
-
100
Circuit
Breakers
3
A
DB
-
75
and
DB
-
100
Three
Position
Operating
Mechanism
4
Adjusting
Limits
of
Main
and
Arcing
Contacts
for
DB
-
75
and
DB
-
100
Cir
-
cuit
Breakers
5
Closing
Solenoid
—
Construction
Details
.
6
Cross
-
Sectional
View
of
Overqurrent
Tripping
Device
with
Long
Delay
and
Instantaneous
Elements
.
7
Schematic
and
Typical
Time
-
Current
Characteristics
of
Overcurrent
Trip
-
ping
Device
with
Long
Delay
and
Instantaneous
Elements
8
Cross
-
Sectional
View
of
Overcurrent
Tripping
Device
with
Long
Delay
and
Short
Delay
Elements
8
A
Selective
Overcurrent
Trip
Operations
9
Schematic
and
Typical
Time
-
Current
Characteristics
of
Overcurrent
Trip
-
ping
Device
with
Long
Delay
and
Short
Delay
Elements
10
A
Schematic
Diagram
of
Overcurrent
Tripping
Device
with
Instantaneous
Element
Only
10
B
Typical
Time
-
Current
Characteristics
of
Overcurrent
Tripping
Device
with
Instantaneous
Element
Only
11
Control
Relay
—
Construction
Details
.
'
12
Shunt
Trip
Attachment
—
Construction
Details
13
Undervditage
Trip
Attachment
—
Construction
Details
.
14
Undervoltdge
Time
Attachment
—
Construction
Details
15
Auxiliary
Switch
—
Construction
Details
16
Alarm
Switch
Attachment
—
Construction
Details
17
Electrical
Lockout
Attachment
—
Construction
Details
18
Key
Lock
or
Key
Interlock
Attachment
—
Construction
Details
19
Rectifier
Unit
for
A
-
C
Undervoltage
and
Electrical
Lockout
Attachments
.
.
.
.
31
20
Reverse
Current
Trip
Attachment
—
Types
"
DB
-
75
"
and
“
DB
-
100
"
Air
Circuit
Breakers
21
Cross
-
Section
View
of
Field
Discharge
Pole
Unit
9
10
11
12
13
15
16
17
18
19
20
21
22
.
/
<
•
/
-
23
24
t
:
24
;
i
25
1
26
27
28
28
29
29
30
32
33
;
v j
4
Courtesy of NationalSwitchgear.com

\
*
3
LB
.
33
-
850
-
4
&
5
D
“
DB
”
AIR
CIRCUIT
BREAKERS
WESTINGHOUSE
"
AIR
CIRCUIT
BREAKERS
w
TYPE
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
-
ulai
^
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
.
.
*
r
5
Courtesy of NationalSwitchgear.com

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Courtesy of NationalSwitchgear.com

I
.
B
.
33
-
850
-
4
&
5
D
“
DB
”
AIR
CIRCUIT
BREAKERS
PART
ONE
RECEIVING
,
HANDLING
AND
STORING
TYPES
“
DB
-
75
”
AND
“
DB
-
100
”
AIR
CIR
-
CUIT
BREAKERS
are
shipped
in
wooden
crates
with
all
attachments
mounted
in
place
.
Important
:
To
avoid
damage
to
the
break
-
ers
,
do
not
use
hooks
in
handling
.
a
.
Observe
whether
all
parts
are
in
proper
alignment
and
move
freely
.
b
.
Be
sure
that
the
contacts
are
clean
and
properly
aligned
.
The
center
finger
of
the
stationary
arcing
contacts
should
have
a
slight
lead
.
C
.
The
hinge
end
of
the
moving
contact
is
lubricated
with
graphite
grease
and
is
therefore
black
.
For
a
description
of
contact
alignment
refer
to
"
CONTACTS
"
,
Page
14
.
4
.
If
the
contacts
are
in
alignment
and
all
parts
move
freely
,
continue
the
closing
until
the
breaker
is
latched
.
5
.
Hold
the
maintenance
operating
handle
down
.
Push
the
"
Push
to
Trip
"
button
to
trip
breaker
.
a
.
The
toggle
linkage
should
collapse
and
the
moving
contact
assembly
move
freely
to
the
full
open
position
.
This
should
be
followed
by
complete
resetting
of
the
links
in
the
toggle
mechanism
as
the
handle
is
raised
.
b
.
The
links
must
always
be
free
to
move
with
-
out
friction
or
binding
.
6
»
Check
the
attachments
for
operation
in
accord
-
ance
with
the
appropriate
instructions
as
given
under
"
Maintenance
"
,
Part
III
of
this
book
.
Note
:
It
is
not
advisable
to
lubricate
any
parts
o
£
the
breaker
.
The
lubrication
supplied
during
factory
assembly
is
sufficient
for
years
of
service
.
The
lubricant
is
of
a
special
form
which
is
used
sparingly
.
The
addition
of
oil
will
only
promote
the
accumulation
of
dust
and
dirt
.
I
Table
No
.
1
NET
WEIGHTS
OF
3
POLE
BREAKER
DB
-
75
475
lbs
(
Add
50
lbs
for
D
.
O
.
)
DB
-
100
525
lbs
(
Add
75
lbs
for
D
.
O
.
)
DBF
-
40
550
lbs
(
Add
75
lbs
for
D
.
O
.
)
Immediately
upon
receipt
,
examine
shipment
for
any
loss
or
damage
incurred
during
shipment
.
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
.
INSPECTION
The
"
DB
"
breaker
assembly
consists
of
a
co
-
or
-
dinated
group
of
^
ub
-
assemblies
mounted
on
a
sup
-
porting
panel
.
The
^
complete
breaker
assembly
is
to
be
mounted
with
the
panel
in
a
vertical
position
.
All
inspections
for
proper
operation
should
,
therefore
,
be
made
with
the
breaker
in
this
position
.
Final
in
-
spection
should
preferably
be
made
with
the
break
-
er
in
its
permanent
mounting
.
Inspect
the
breaker
as
follows
:
1
.
Lift
trip
finger
by
hand
to
make
sure
that
it
does
not
bind
.
2
.
Remove
any
foreign
particles
from
the
hinge
end
of
the
moving
contacts
.
3
.
Insert
the
maintenance
operating
handle
and
slowly
close
the
breaker
.
STORING
If
circuit
breakers
are
not
to
be
installed
in
their
permanent
locations
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
which
are
apt
to
absorb
moisture
.
FOR
SAFETY
REASONS
,
STORE
THE
BREAKER
IN
THE
OPEN
POSITION
,
7
Courtesy of NationalSwitchgear.com

tr
1
.
PART
TWO
r
INSTALLATION
CONNECTIONS
Type
"
DB
"
circuit
breakers
are
furnished
as
complete
unit
assemblies
and
the
installation
con
-
sists
of
:
(
1
)
bolting
them
to
the
supporting
frame
-
work
or
structure
;
(
2
)
connecting
the
current
carry
-
ing
cables
or
bus
bars
;
and
(
3
)
completing
any
secondary
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
installation
is
being
made
.
Mounting
dimensions
and
details
of
the
front
en
-
closure
cutouts
are
shown
in
Figs
.
1
,
1
A
,
IB
,
and
1
C
.
To
prevent
distortion
of
the
breaker
panel
,
the
supporting
structure
should
be
checked
for
align
-
ment
.
Magnetic
material
in
the
mounting
structure
should
have
at
least
two
inches
clearance
to
the
breaker
studs
.
A
manual
closing
handle
is
supplied
with
each
order
of
DB
-
75
and
DB
-
100
breakers
.
This
handle
is
for
maintenance
only
and
in
no
case
should
it
be
used
for
closing
the
breaker
when
primary
circuit
is
energized
.
Typical
circuit
breaker
wiring
diagrams
are
shown
in
Fig
.
2
,
The
connecting
cables
or
bus
bars
should
have
adequate
current
carrying
capacity
,
or
heat
will
be
conducted
to
the
circuit
breaker
resulting
in
possible
excessive
temperature
rise
.
Connecting
cables
or
bus
bars
must
be
supported
so
that
the
circuit
breaker
studs
will
not
be
subjected
to
unnecessary
stresses
.
ENCLOSURES
The
breaker
is
normally
mounted
in
the
enclosure
along
with
accompanying
bus
work
terminating
in
cable
clamps
.
Where
covers
are
mounted
on
en
-
closures
,
they
are
to
be
removed
and
drilled
to
provide
for
connecting
cable
,
All
connections
should
be
clean
,
smooth
and
free
from
burrs
to
assume
full
contact
area
.
They
should
be
firmly
clamped
or
bolted
in
place
to
prevent
excessive
heating
.
Cable
must
be
adequately
braced
to
withstand
full
short
circuit
currents
.
-
)
£
f
;
»
<
5
V
•
1
'
8
Courtesy of NationalSwitchgear.com

!
V
.
l
\
I
.
B
.
33
-
850
-
4
&
5
D
INSTALLATION
“
DB
”
AIR
CIRCUIT
BREAKERS
*
4
»
*
:
v
%
*
<
r
•
••
V
I
7
FIG
.
1
.
Type
DB
-
100
Air
Circuit
Breaker
,
Outline
and
Mounting
Dimensions
9
Courtesy of NationalSwitchgear.com

I
INSTALLATION
.
4
*
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FIG
.
1
A
.
Typo
DB
-
75
Air
Circuit
Breaker
.
Fixed
Outline
and
Mounting
Dimensions
10
Courtesy of NationalSwitchgear.com