Electrical Flashcards
How many generators are there?
Four (GEN 1, GEN 2, APU, EMER GEN)
How many batteries are there?
2
What do the batteries provide?
DC, 28V
What do the Generators provide?
AC: 115/200V, 400Hz, 3 phase
Why do the batteries need to be 25.5V or higher during Cockpit Preparation? (2 reasons)
1) 25.5V is the minimum charge required for APU FIRE TEST / APU START.
2) A voltage at or below 25.5V may result in the discharge of the APU FIRE extinguisher bottle.
What does a TR do and how many are there?
Convers AC to DC
3 (TR 1, TR 2, ESS TR)
What is a SI and what does it do?
A Static Inverter and it converts DC to AC
What type of electricity do the Generators produce?
AC
What type of electricity do the batteries produce?
DC
What is the IDG and how does it work?
Integrated Drive Generator. It regulates the rotational energy of the engine. It is connected by a shaft from the Accessory Gear Box to the Generator. If it is INOP, you loose the Generator
How many kVa do the Generators produce?
90kVa, enough to run the whole plane.
What does the Accessory Gearbox do?
It takes the rotational energy of the engine and slows it down for the engine driven accessories e.g. IDGs, HYD ENG pumps.
Why is there no IDG on the APU?
Because the N% is constant, it is a fixes value.
In a normal configuration, with both engines running, how is each bus powered?
GEN 1 - AC BUS 1 - TR 1 - DC BUS 1 - DC ESS BUS - DC BAT BUS
GEN 2 - AC BUS 2 - TR 2 - DC BUS 2
What is the role of the BUS TIE?
The BUS TIE connects both sides of the electrical system together. When it is turned off, the sides are isolated from each other.
