Saab 340B, Руководство по эксплуатации

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ELECTRICAL
Description
Aircraft Operations Manual
5.1
PAGE 23
Jun 01/19
3. CONTROLS AND INDICATORS
BUS TIE CONN (green).
Comes on when the L and R GEN BUS
are connected.
EXT PWR ON light (white).
Comes on indicating that external power is
switched on when the EXT PW’switch is in ON
position. The light is controlled by the external
power relay and will subsequently only come
on when external power is available.
EXT PWR switch.
In ON position the external power relay closes
if external power is available thereby enabling power
to all busses (Fig. 3).
External power has priority over the DC
− generators
and batteries.
The EX PWR switch lever will automatically retard to
the OFF position if the external power relay
de − energized due to external power voltage drop.
L/R BAT switch.
Controls the battery relay connecting the battery
to the START BUS and the respective GEN BUS/
OVRD
− Battery thermal switch overridden and
battery connected after a battery over −
heat and subsequent relay opening,
independent of EXT PWR switch posi −
tion (for emergency use only).
ON − Relay energized and battery connected
if EXT PWR switch is OFF.
OFF − Relay de − energized and battery
disconnected from the above buses.
BUS TIE switch.
Controls the BUS TIE relay for connect of the
L and R GEN BUS.
CONN
− The BUS TIE relay is energized with
power from the emergency bus and the
generator buses are connected.
AUTO − The BUS TIE relay is energized and the
generator buses are connected with
batteries ON and one or both generators
not working. With both generators
working the generator buses are not
connected.
SPLIT − The BUS TIE relay is de − energized and
the busses not connected.
L/R MAIN BUS light (amber)
Comes on when the respective bus is not
powered.
The L/R main bus are de
− energized:
− During engine start.
− When the L/R generator bus are battery
powered.
− When the MAIN BUS relay has tripped due to
tripped generator.
L/R GEN OV TEMP light (amber).
Comes on when the respective generator is
overheated (150

C).
L/R GEN light (amber).
Comes on when the generator relay is de −
energized, disconnecting the generator from
the generator bus.
L/R GEN switch.
The GEN switch controls the respective generator
relay connecting the generator to respective gen-
erator bus.
OFF
− The generator is disconnected from it’s
bus.
ON − The generator control unit allows the
generator relay to close provided that
the engine is running and the generator
provides sufficient electrical power and
that no failures are detected.
RESET − The generator field relay and the gen −
erator relay are closed again through
the generator control unit after having
been switched off or tripped.
NOTE: Pulling the fire handle will trip the
field relay.
C0808
A
A
DC PANEL
Fig. 11 DC Power Control Panel − switches and light