Cessna 182 1973 - Ground Service Plug Receptacle; Static Pressure Alternate Source Valve

GROUND
SERVICE
PLUG
RECEPTACLE.
A
ground
service
plug
receptacle
may
be
installed
to
permit
use
of
an
external
power
source
for
cold
weather
starting
and
during
lengthy
main-
tenance
work
on
the
airplane
electrical
system
(with
the
exception
of
elec-
tronic
equipment).
NOTE
Electrical
power
for the
airplane
electrical
circuits
is
pro-
vided
through
a
split
bus
bar
having
all electronic
circuits
on
one
side
of
the bus
and
other
electrical
circuits
on
the
other
side
of
the bus.
When
an
external
power
source
is
connected,
a
contactor
automatically
opens
the
circuit
to
the
electronic
portion
of
the
split
bus
bar
as a
protection
against
damage
to
the
transistors
in the
electronic
equip-
ment
by
transient
voltages
from
the
power
source.
There-
fore,
the
external
power
source
can
not
be
used
as
a
source
of
power
when
checking
electronic
components.
Just
before
connecting an
external
power
source
(generator
type or
bat-
tery
cart),
the
master
switch
should
be
turned
"ON."
.
The
ground
service
plug
receptacle
circuit
incorporates a polarity
re-
versal
protection.
Power
from the
external
power
source
will
flow
only
if
the
ground
service
plug
is
correctly
connected to
the
airplane.
If
the
plug
is
accidentally
connected
backwards,
no
power
will
flow
to
the
airplane's
electrical
system,
thereby
preventing
any
damage
to
electrical
equipment.
The
battery
and
external
power
circuits
have
been
designed
to
com-
pletely
eliminate
the need
to
"jumper'
across
the
battery
contactor to close
it
for
charging
a
completely
"dead
battery.
A
special
fused
circuit
in
the
external
power
system
supplies
the
needed
"jumper"
across
the
contacts
so
that
with
a
'"dead"
battery
and
an
external
power
source
applied, turning
the
master
switch
"ON"
will close the
battery
contactor.
STATIC
PRESSURE
ALTERNATE
SOURCE
VALVE.
A
static
pressure
alternate
source
valve
is
available
to
provide
con-
tinued
operation
of
the
airspeed indicator,
altimeter
and
vertical
speed
indicator
in
the event
that
the
static
system
ports
or
lines
become
ob-
structed.
7-2