GENERATORS
Two engine-driven starter/generators, one on
each engine accessory section (Figure 2-7),
provide the normal source of 28 VDC power.
Each starter/generator is rated at 30 VDC, and
limited to 300 amperes. Unless a GPU is pow-
ering the airplane electrical system, the gen-
erator will automatically come on-line when
the DEEC determines the engine is up to speed
(approximately 95% of N1 idle). If the en-
gine is in manual mode, the GEN S/I must be
depressed to bring the generator on line after
engine start. If a GPU is used for engine start,
the generators will automatically come on-
line after the engines are running when the
GPU is disconnected, or when the EXT PWR
switch on the electrical control panel is de-
pressed.
Inflight, cooling air is routed from a scoop on
the engine nacelle to the starter/generator
(Figure 2-8). Cooling while on the ground is
provided by a fan mounted on the generator
shaft.
During normal operation, both generators op-
erate independently. When both generators
are on-line, the bus-tie will normally be open
and the left generator will recharge the left
main battery and the right generator will
recharge the right main battery and the emer-
gency battery. The generators supply DC
power to all DC powered equipment on the air-
plane under normal conditions.
L E A R J E T 4 5
P I L O T T R A I N I N G M A N U A L
2-7
FOR TRAINING PURPOSES ONLY
FlightSafety
international
DEEC
ALTERNATOR
STARTER/GENERATOR
HYDRAULIC PUMP
MOTIVE FLOW
FUEL PUMP
Figure 2-7. Starter/Generator
ALTERNATOR
AIR SCOOP
GENERATOR
AIR SCOOP
Figure 2-8. Alternator and Generator Air Scoops