GE POWER/VAC 4.16 - Bus Compartment; Current Transformer Compartment; Primary Termination Space; Voltage Transformers

clad
studs
,
the
spring
force
on
the
fingers
is
divided
between
the
breaker
stud
and
metal
-
clad
studs
.
See
Fig
.
12
.
On
3000
ampere
primary
disconnects
,
silver
-
plated
copper
fingers
are
positioned
in
a
circular
configuration
and
are
supported
by
a
non
-
magnetic
spider
.
This
spider
spaces
the
fingers
equally
around
the
breaker
stud
and
fastens
them
to
the
end
of
the
stud
.
The
fingers
are
held
in
contact
with
the
breaker
stud
by
a
stainless
steel
garter
spring
.
A
second
garter
spring
on
the
outer
end
of
the
finger
provides
contact
pressure
when
the
finger
assembly
is
connected
to
the
tube
in
the
metal
-
clad
unit
.
See
Fig
.
12
.
PRIMARY
TERMINATION
SPACE
The
primary
termination
space
of
each
breaker
unit
is
isolated
from
the
other
equipment
by
metal
barriers
.
Space
is
provided
in
this
compartment
for
connecting
the
pur
-
chaser
’
s
primary
cable
by
means
of
potheads
or
clamp
-
type
terminals
.
Two
-
hole
NEMA
drilling
for
two
cables
per
phase
is
provided
at
all
cable
connection
points
.
In
double
breaker
vertical
sections
,
a
steel
duct
serves
as
a
pull
-
box
and
barrier
to
separate
the
two
outgoing
cable
circuits
.
t
The
primary
termination
space
of
a
unit
is
accessible
by
removal
of
the
bolted
rear
cover
.
BUS
COMPARTMENT
The
main
buses
are
enclosed
in
a
metal
compartment
with
removable
front
covers
to
provide
accessibility
.
The
bus
is
supported
and
insulated
by
molded
glass
-
reinforced
polyes
-
ter
barriers
which
are
flame
retardant
and
track
resistant
.
Polyester
supports
with
porcelain
sleeves
may
be
furnished
as
a
customer
option
in
5
and
15
kV
equipment
.
Bus
bars
are
insulated
with
an
extruded
thermoplastic
insulation
sleeving
or
an
applied
epoxy
insulation
using
the
fluidized
bed
process
.
All
bolted
joints
have
silver
-
to
-
silver
connections
for
low
contact
resistance
.
Most
joints
are
in
-
sulated
with
a
molded
polyvinylchloride
boot
.
VOLTAGE
TRANSFORMERS
Voltage
transformers
are
located
in
an
auxiliary
unit
.
Up
to
three
transformers
can
be
mounted
on
a
movable
carriage
equipped
with
primary
and
secondary
disconnect
-
ing
devices
.
When
the
voltage
transformers
are
discon
-
nected
,
they
are
at
a
safe
striking
distance
from
all
live
parts
of
the
switchgear
.
In
addition
,
a
grounding
device
is
provided
which
contacts
the
fuses
when
the
voltage
transformers
are
disconnected
,
effectively
discharging
the
transformers
.
In
this
position
the
transformer
fuses
may
be
safely
removed
and
replaced
.
A
barrier
mounted
at
the
rear
of
the
carriage
moves
with
the
carriage
to
a
position
in
front
of
the
station
-
ary
part
of
the
primary
disconnect
device
,
providing
a
safe
striking
distance
from
all
live
parts
.
See
Fig
.
14
.
CURRENT
TRANSFORMER
COMPARTMENT
Current
transformers
are
mounted
over
the
primary
bushings
in
the
rear
of
the
breaker
compartment
and
are
isolated
from
the
breaker
by
the
shutter
barrier
.
They
are
front
-
accessible
by
removal
of
the
shutter
barrier
.
The
equipment
must
be
de
-
energized
before
any
component
is
touched
or
serious
injury
could
result
.
CURRENT
-
LIMITING
FUSES
AND
CONTROL
POWER
TRANSFORMER
Current
-
limiting
fuses
with
high
interrupting
rating
are
sometimes
used
in
metal
-
clad
switchgear
to
protect
small
transformers
or
circuits
where
circuit
breakers
cannot
be
economically
or
functionally
justified
.
Fig
.
15
Control
Power
Transformer
Drawout
Carriage
Voltage
Transformer
Drawout
Carnage
19
Courtesy of NationalSwitchgear.com