Hawker 800 XP, Руководство по подготовке пилотов

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Engine Starting
The function of the engine starting circuits
during the full starting sequence is described,
together with the associated controls and in-
dicators, in Chapter 7, “Powerplant.” The elec-
trical functions of starting, as well as other
circuit configurations, are as follows and are
shown in Figures 2-8 through 2-16.
External Start
With external power connected, a supply is
available at the EXT PWR switch. Setting this
switch to ON completes a circuit, via nor-
mally closed contacts of an internal start con-
tactor to energize a ground supply contactor.
With this contactor energized, ground power
is connected to all bus bars. With the BATT
switch at ON position, pushing the START
PWR switch on illuminates an integral PWR
ON/PUSH FOR ABORT annunciator and
brings the start circuit to a state of readiness
for ENGINE START switch selection.
Internal Start
Setting the BATT switch to ON and pushing
the START PWR switch on energizes the in-
ternal start contactor via closed contacts of the
deenergized ground supply contactor. These
selections connect Nos. 1 and 2 batteries in par-
allel to the starter bus bar and bring the start
circuit to a state of readiness for ENGINE
START switch selection.
The PE bus bar remains energized during a nor-
mal internal start.
For either type of start the starting sequence may
be terminated at any time by a second applica-
tion of the START PWR switch (now annunci-
ating “PWR ON/PUSH FOR ABORT”). This
action deenergizes the internal start contactor
and the engine start contactor to isolate the start
circuits and extinguish the PWR ON/PUSH
FOR ABORT and OPERATING lights.
Power Generation
The transition from starting to generating
mode is performed automatically by the GCU.
The GCU senses a reference voltage and sig-
nals a generator line contactor (GLC) to close,
thus connecting the generator to the associated
bus bar (PS1 or PS2). When a GLC closes, the
associated GEN FAIL light goes out.
In the generating mode, the GCU operates as
a voltage regulator. The GCU also signals the
GLC to open when reverse current, overexci-
tation, or overvoltage is detected. Addition-
ally, to avoid reverse current flow, the GCU
prevents closure of the GLC when bus bar volt-
age is higher than the generator terminal volt-
age.
NOTE
Overvoltage and overexcitation, in
addition to opening the GLC, also
trips the generator field circuit. The
opening of the field circuit occurs
u p o n d e t e c t i o n o f t h e s e f a u l t s
whether or not the GLC is closed.
2-8
FOR TRAINING PURPOSES ONLY
HAWKER 800 XP PILOT TRAINING MANUAL
FlightSafety
international
Figure 2-7. Generator Cooling