Learjet 60 - Avionics Master Switch; Avionics Power System

Pilot's Manual

Learjet 60
NOTE
4-16
1 .
DC power
for
the
primary pitch trim
motor
will
be switched
from
the battery
charging
bus to the
#1
aircraft battery
.
2 .
DC power
for
the
auxiliary hydraulic
pump
will
be switched
from
the battery
charging
bus to the
#2
aircraft battery
.
3 . DC power to heat the standby pitot-static probe
will
be
switched
from
the battery
charging
bus to the
#2
aircraft battery
.
4 .
DC powered equipment on the emergency buses
will
be
switched
from
the associated DC BUS
1
to the aircraft batteries .
5 .
The
DC voltmeter
will
display the voltage of both batteries
(EMER
BUS
TIE
must be closed) .
1
AVIONICS POWER SYSTEM
AVIONICS MASTER SWITCH
" The conditions just described assume that both
BATTERY
switches are in the On position .
" If only the BATTERY 1 switch is On, the auxiliary
hydraulic pump will not be available, heat for the
standby pitot-static probe will not be available,
and the DC voltmeter will display the voltage of
the #1 battery . All other conditions will be as de-
scribed .
" If only the BATTERY 2 switch is On, Primary
Pitch Trim will not be available and the DC volt-
meter will display the voltage of the #2 battery .
All other conditions will be as described .
An avionics power system is installed to allow selected DC powered
avionics systems to be powered up through the use of two master
switches . The system consists of a LEFT MASTER and RIGHTMAS-
TER switch, and a control relay in each circuit breaker panel . The con-
trol relays operate on 28 VDC supplied through the corresponding l-
amp AVIONICS MASTER circuit breaker in the associated circuit
breaker panel . The AVIONICS MASTER switches have no effect when
EMER BUS is selected and the generators are off-line .
The LEFT MASTER switch is installed in the pilot's switch panel and
the RIGHT MASTER switch is installed in the copilot's switch panel .
These two switches allow the crew to turn groups of avionic equipment
off and on with only two switches .
Refer to the Airplane Flight Manual for a listing of equipment con-
trolled by the MASTER switches . The actual equipment affected may
vary with customized wiring options .
PM-123
Change 5