_ current ( _ ) is the primary source of power
Alternating, AC
The primary electrical system consists of two _ systems each capable of supplying the _ helicopter power requirements
Independent, total
The prime source of each system is a _ VAC generator
115/120
A subsystem feeds independent _ buses and a _ reference bus
Primary, 26 VAC
A portion of each _ primary bus load is _ to 28 volts direct current (VDC) by 2 _ _ AC/DC _
AC, converted, 400 ampere , converters
A 26 VAC _ bus is used to provide _ reference for use on the stabilator system
Reference, stable
2 _ VDC 5 amp-_ sealed _ acid batteries (SLAB) provide power to independent batteries, battery utility, and _ essential buses
24, hour, DC
SLABs provide uninterrupted emergency power for _ and at night with 80% charged batteries _ of power is available with all _ electrical equipment on
15 min , 12min, DC
Operating with a _ charged or malfunctioning #1 battery could prevent proper _ operation and _ of firefighting capabilities on the #1 _ and _ in addition to _ battery-only time available
Low, APU, loss, engine, APU, reducing
Auxiliary AC power is provided by the _
APU
The APU is only capable of providing power to the aircraft electrical system when the main _ are _
Generators, offline
If the APU is the only source of _ _ , the _ _ system cannot be run while the _ _ is operating
AC power, windshield anti-ice, backup pump
_ operation requires at least _ main _ online and operating
Blade - de ice , 1 , generator
Equipment available with battery power only
2 ADC / #2 DCU / #2 EGI #1 stabilator actuator / #1 FM
APU system control, Backup pump control,
MFD, ICS, lights (compass, cockpit), FDR, CVR
The generator control unit _ voltage from the #1/#2/ and APU generators and takes the generator’s offline when malfunctions occur
The GCU provides (FUUOv)
Monitors
Feeder fault
Under frequency protection (375 +/-)
Hz
Under voltage protection (100 +/-) vac
Overvoltage protection (125 +/- VAC)
SLAB batteries last for _ with the _ off if it’s the sole source of power
15min
Searchlight
If _ power is not available, only the _ fire bottle can be used
Firefighting capability in the _ will be lost
AC
RESERVE
2
