Electrical System Flashcards
How is the aircraft primarily powered?
AC Power
What are the components of the AC power?
- 2 Integrated Drive Generators (IDG)
- AC Ground Power Unit (GPU)
- Auxiliary Power Unit (APU)
- 1 Invertor
- 1 Ram Air Turbine (RAT)
What are the components of the DC power?
- 2 Sealed Lead Acid Batteries (SLAB)
- 3 Transformer Rectifier Units (TRU)
- DC External Power Source (DC GPU)
What does a Transformer Rectifier Unit (TRU) do?
TRUs convert AC power into DC power.
What is connected to the AC ESSENTIAL BUS?
- AC FUEL PUMP 2A
- ACMP 3A
- SF-ACE 1 FLAP CH 1 AC FEED
- SF-ACE 2 SLAT CH 2 AC FEED
What happens if an AC power source fails?
The AC buses are automatically connected by the bus tie contactors (BTCs). One AC power is enough to supply all power. To protect against a overload the system will LOAD SHED the galleys and right windshield heat.
How many volts are the batteries?
24 volt sealed lead acid batteries.
When is the Hot Battery Bus powered?
It is always powered.
Can the fueling panel be used when no power is on the aircraft?
Yes, because the refuel panel is connected to the hot battery bus.
When turning the batteries to provide power, what should the volts be at?
Minimum voltage is 22.5V.
When one or both batteries are below 22.5, reference the SOPM battery charging table.
When less than 21V, write it up and call maintenance.
What happens when selecting DISC on one of the IDGs?
It mechanically disconnects the IDG from the AC bus. Reset required by maintenance.
What does the yellow light next to the IDGs sense?
High Oil Temperature or Low Oil Pressure
What type of circuit breakers are there?
Thermal and Electronic. Some thermals can be accessed in the flight deck. All electronic are accessed through the MCDU.
How long can the batteries supply essential loads for?
10 minutes.
