Electrical Flashcards
What is the primary source of electrical power in the system / where does it come from / what is the driving force behind all of it?
Alternating Current (ac) supplied by two main generators driven by the transmission
The APU generator and external power can also supply ac power.
What is a secondary source of ac power?
APU-driven generator
External ac power can also be connected when on the ground.
How is dc electrical power supplied in the system / What is the conversation rate?
By two converters converting 115-volt ac power to 28-volt dc power
A 24-volt dc Nickel-Cadmium (NICAD) battery serves as a secondary source.
What are the two types of electrical power distribution systems mentioned?
Ac and dc electrical distribution systems
Each system has its own set of buses.
How many electrical buses are in the ac electrical distribution system / List the buses?
Five electrical buses
Including No. 1 and No. 2 ac primary buses, ac essential bus, AC Secondary bus, and AC Monitor bus.
What happens when the N r drops below 94 percent with WOW?
The GCU removes the main generator electrical input from the entire ac power distribution system.
What is the minimum N r required for the GCU to reconnect generators to the ac electrical distribution system?
97 percent N r
What is the function of the Generator Control Unit (GCU)?
Connects generators to the ac electrical bus, regulates output, protects components, and monitors voltage level and frequency.
What should be done to connect external power to the aircraft electrical bus system?
Toggle the EXT PWR switch to RESET, then ON.
What does the Battery Utility bus receive power from?
The battery regardless of switch position
What does the battery analyzer/conditioner monitor?
Battery system for fault conditions, charge, temperature, and cell conditions.
What happens if both dc converters fail?
Both dc primary buses are dropped.
What is the emergency electrical power source if both dc converters fail / Which busses will it charge/ at what point will this source tap out?
The battery will provide emergency power to the Battery bus and the dc essential bus if the battery is above a 35 percent charge.
What does the FAULT caution indicate?
Battery overtemperature or cell dissimilarity condition.
True or False: The APU generator is connected (On) to the ac electrical distribution system while both main generators are operating.
False
