Cessna 172SPHUSR05 Pilot Operating Handbook page 471

CESSNA
MODEL 1 72S
Power is supplied to the 1 2-volt Cabi n Power System from a DC
to DC power converter located in the tailcone of the aircraft. The
power converter receives 28 VDC power from the "CABI N
L TS/PWR" circuit breaker located o n the e lectrical switch/circuit
b reaker panel . By using two small signal pins located in the Cabin
Power System connector, the power converter will not supply power
to the Cabin Power connector when there is nothi n g plugged i n .
Refer t o 1 4 C F R 9 1 .21 and Advisory Circular No. 9 1 .2 1 - 1 0 " Use
of Portable Electronic
information and req u i rements regarding the use of portable
electronic devices in aircraft.
T h e following limitations m ust b e adhered to:
1 . The 1 2 Volt Cabin Power System is not certified for supplying
power to flight-critical communications or navigation devices.
2. Use of the 1 2 Volt Cabin Power System is prohibited during
takeoff and landing.
3. Use of the 12 Volt Cabin Power System is prohibited u nder
I FR
unless the operator of the aircraft has determ ined
use of the 1 2 VDC power supply and the connected portable
electronic device(s) wil l not cause interference with the
navigation or communication systems of the airp lane.
E M E R G E N CY P R O C E D U R ES
There is no change to the airplane emergency procedures when
the 1 2 Volt Cabin Power System is i nstalled.
disabled by unplugging the power or adapter cable from the 1 2 Volt
Cabin Power System connector.
failure, load shedding of nonessential auxiliary equipment m ay be
accomplished by simply unplugging equipment from the connector.
Dec
30/00
SECTIO N 9 - SUPPLEM ENTS
SU PPLE M ENT 22 - FAA APPROVED
Devices Aboard
2
S E CTION
L I M ITATIO N S
S ECTI O N 3
In the event of an alternator
Aircraft" for further
that the
The system is