ELECTRICAL
Operation
Aircraft Operations Manual
5.2
PAGE
3
Apr 01/15
CONDITIONS
NORMAL PROCEDURES
2.2
ELECTRICAL
SYSTEM
POWER UP
External power
EXTERNAL-
POWER
2.1 Battery power must be connected before applying External power.
NOTE
1.
EXT PWR AVAIL light
CHECK ON
. . . . . . . . . . . . . . . . . . . . . . . . . . .
External power available is indicated by EXT PWR AVAIL light ON
2.
EXT PWR voltage
CHECK
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
−
Check EXT PWR below 30 V.
3.
EXT PWR switch
ON
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
−
Check EXT PWR light to come on and check EXT PWR voltage to indicate
between 26 V and 29 V.
−
Check L and R BAT light to come on indicating that batteries are discon-
nected from the generator and start busses.
−
Check BUS TIE CONN light to remain on.
If the external power voltage should drop to approximately 10 volts the EXT
PWR switch lever automatically retard to the OFF position and the batteries will
be connected. The external power relay will automatically be deenergized.
If leaving the aircraft with external power ON, make sure to switch OFF the
batteries otherwise the batteries could be drained if the external power is
disconnected from outside the aircraft.
NOTE
2.3
ENGINE START
For Electrical system operation during engine start and during engine opera-
tion see section 17 POWER PLANT.
