E AC Distribution Systems Flashcards
What is the role of a bus bar?
A low resistance conductor that forms a common connection for loads and consumers
Main benefit of bus bars?
Significantly reduce the amount of wiring required
What does the AC bus do?
Used for supply and fault monitoring
What does the DC bus do?
Used for supply and monitoring
What does the emergency/essential bus do?
Loads essential for flight receive power from here
What does the battery bus do?
Allows the battery to be connected to the DC bus for distribution of battery power or charging
What does the hot bus do?
Directly connect to battery terminals, used for permanent functions such as flight deck clock
What does the ground/maintenance bus do?
Allows connection of external AC power so ground staff can use aircraft electrical equipment whilst on the ground
What does the shed bus do?
Non-essential loads are connected here, this bus allows shedding in an emergency
What is a uni-pole connection?
The electrical system uses the aircraft structure as a common earth return
What is a dipole connection?
2 wire connection required as the structure cannot be used as an earth
What is the power priority acronym?
GEARB
What does the G mean in GEARB?
Generator 1 or 2 (90 KVA each)
What does the E mean in GEARB?
External/ground power (unlimited)
What does the A mean in GEARB?
Auxiliary power unit (90 KVA)
