Aircraft Electrical Systems Flashcards
How many alternators power an aircraft?
-Normally one
-Older aircraft have one generator
What are batteries for in an aircraft?
-For starting and emergencies
-They can be disconnected from the system
-The are not needed in normal flight
How are circuits protected?
-Circuit breakers
-Fuses on really old planes
How are circuits completed?
-Through ground, which is the structure of the aircraft.
-It can be assumed that all ground are connected
Aircraft use what type of electrical systems?
Single wire
What two systems are aircraft circuits divided?
Power and Load
What do power circuits connect to? and where can the power come from?
-Power circuits connect power to the bus.
-Power can come from a battery, generator, alternator, or a GPU.
When an ammeter is wired to each end of a shunt it is not really an ammeter but a?
Micro voltmeter
The shunt is a _____ with known_____. Therefore it will?
-conductor with known resistance.
-Drop a certain amount of voltage as power runs through it
When alternator output is high or low?
-The voltage is at its peak
-The voltages is at its minimum
Even though the ammeter is marked in amps its responding in?
Changes in voltage
What is a zero-center ammeter?
To show at a glance whether the battery is being charged by the alternator or discharging because the alternator output is too low.
When does a normally closed solenoid open?
When it is energized
Why do alternators need to share the load?
One will take over and probably fail while the other one is doing nothing.
How do you avoid excessive flow in a circuit?
By a device that will open the circuit
Where are circuit breakers located any why?
-As near the source as possible
-They are protecting the aircraft wiring
-Individual components may have their own CB’s or fuses
What are Current Limiters?
A type of slow blow fuse that allows a large amount of current to flow for a short length of time but opens if to much current flows for a long period