Aircraft Electrical Systems Flashcards
What is the purpose of a circuit breaker?
The purpose is to protect wiring from over-current conditions that may result in meltdowns and fires.
What tools is used to measure the size of unmarked electrical wire?
A wire gauge.
What are the colors of aircraft position lights and where are the mounted?
Position lights are red, green and white. Green is located on the tip of the right wing, red on the tip of the left wing, and white on the vertical stabilizer or where it is visible from the rear of the aircraft.
What are the factors to be considered when selecting wire size for electrical power?
Current capacity, voltage drop, and power loss.
When is a circuit breaker or fuse designed to open the circuit?
The circuit breaker or fuse used must be rated at a value below which its associated wiring and wire insulation would begin to burn.
What are the three most common faults that occur in an electrical circuit?
Open circuits, short circuits, and circuits with lower-than-expected power consumption.
What size electrical conduit should be used for a specific cable bundle?
Inside diameter of 25% more than the diameter of the wire bundle.
When should electrical switches be derated from their normal current rating?
For circuits with equipment that have high turn-on currents such as incandescence lamps, solenoids, relays, and DC motors.
When do DC electrical motors draw several times their rated current?
At turn-on, or at starting.
What would cause an AC electric motor to run too fast?
A shorted field winding or excessive supply voltage.
What would cause an AC electric motor to run too slow?
Defective wiring, loss of lubrication, or low supply voltage.
How is the output voltage of an alternator controlled?
Use of a voltage regulator. This regulator controls the exciter field current and therefore the exciter output voltage applied to the alternator field.
What should be checked before any aircraft electrical load is increased?
The associated wire sizes, conductors, and fuse capacity.
What is the main advantage of using AC for aircraft electric power systems?
AC voltages can be stepped up for down easily through the use of transformers.
In AC power systems, how is DC obtained for battery charging?
Through the use of a step down transformer and a rectifier circuit.
