The maximum permissible load on the APU generator is ✔️Ans - 40 kVA.
Select the BATTERY MASTER switch to ON. Verify the main and
APU batteries indicate at least ✔️Ans - 22V on the EICAS DC ELECTRICAL
synoptic page.
The main battery is rated at ✔️Ans - 24 VDC, 17 ampere-hours. The battery
and its AC-powered charger are located in the forward unpressurized
equipment bay.
The APU battery is rated at ✔️Ans - 24 VDC, 43 ampere-hours. The battery
and its AC-powered charger are located in the aft equipment bay
To protect the flight compartment CRT displays, the maximum
permissible time for ground operations with DC power only is ✔️Ans - five
(5) minutes.
CRT 1 & 2 cooling fans are ✔️Ans - AC powered
External Power is available, DC Services are for ✔️Ans - The DC SERV BUS
supplies electrical power to supply lighting for the passenger cabin and the
external navigation lights. It is normally powered by the TRU 2 through DC
BUS 2.
During the start sequence the ECU schedules starter disengagement as a
function of altitude. For example, at sea level, the starter disengages at
approximately ✔️Ans - 46%-60% rpm, as determined by the ECU.
The status message APU START is displayed on EICAS when the starter is
engaged.
APU idles at ✔️Ans - 100%
APU
The green AVAIL switchlight illuminates at ✔️Ans - 99% rpm + 2 seconds,
, The APU electronic control unit (ECU) controls the ✔️Ans - operation of
the APU and determines when the APU is ready for bleed air loading.
The APU load control valve (LCV) is modulated to control the amount of
✔️Ans - bleed air taken from the APU. The ECU controls the opening, closing
and modulation of the LCV
APU Pump ✔️Ans - A dedicated DC-powered APU fuel pump is installed at
the left collector tank
The maximum operating altitude of the APU is ✔️Ans - 41,000 feet
APU starting up to ✔️Ans - 37,000 feet.
APU bleed air extraction is limited to ✔️Ans - 25,000 feet and below.
The 40 kVA APU generator may be utilized up to ✔️Ans - 41,000 feet.
Maximum engine start using APU ✔️Ans - 21,000
How many AC generators are on board the aircraft? ✔️Ans - 2 IDG
1 APU
1 ADG
The ADG is capable of powering the AC ESS BUS when speed is greater than
✔️Ans - 135 KIAS
What does the ADG power? ✔️Ans - Hydraulic 3B
Slats and flaps system (1/2 Speed)
Pitch trim system
AC ESS BUS
ESS TRU 1
FAULT Switchlight in IDG means ✔️Ans - HOT/LOP
High Oil Temperature / Low Oil Pressure