Electrical System Flashcards
Describe the electrical system
2 engine driven generators supply AC electrical power at 115 volts 400 alternating current. Each generator is connected to a drive unit that supply’s a constant frequency to the required busses throughout all phases of flight
What are the two basic principles of the operation for the electrical system
There is no paralleling of the AC sources of power. 
The sources of power being connected to a generator bus automatically disconnects and existing source.
There’s no two sources of Generator power powering the same AC bus
AC power system
Each AC power system consist of a generator bus, a main bus, and a transfer bus.  The left AC power system also includes a ground service bus
What happens if the source powering either AC power system fails, and what will the indication be?
A transfer relay automatically selects the opposite generator bus as an alternate power source for the transfer bus. 
What happens if all AC power fails In-flight and on the ground
AC standby bus is powered by the battery bus through the static Inverter DC standby bus is powered by the battery bus a fully charge battery will provide the minimum of 30 minutes of standby power
Which Relay actually connects the generator to the generator bus?
Generator breaker
What is the load limit for each engine driven generator
125 Amps
Which bus charges the battery charger
In auto the AC ground service bus will power the battery charger.
If the AC ground service bus is not powered the AC main bus two will power of the battery charger.
If the bus transfer switch is selected off and the main bus two is unable to power the battery charger the bus transfer relays are inhibited and the TR three disconnect relay opens.
Does AC power from the engine generators automatically apply to the generator buses when the power is a good quality
No, it must be selected on
With ground electrical power connected to the aircraft, movement of the ground power switch to on will?
Apply ground power to both left and right generator buses
Tell me about the battery
Battery is a 24 V Nickel Cadmium Battery and is located in the electric compartment. The battery is a Standby source of DC power. Battery charging is automatically controlled. A fully charged battery has sufficient capacity to provide standby power for a period of 30 minutes
What is another way the battery can be powered when the battery switches off
Select standby power to “BATT” and the hot battery bus will power the battery
