Electrical Systems Flashcards
What must be done prior to entering load centers to remove or install electrical components?
External power must be disconnected and aircraft power removed.
What does electrical shock do to the human body?
Passes through the body’s nervous system or vascular system to ground.
Disrupts the body’s normal electrical functions, and can stop the heart, lungs or both.
Can cause severe injury or death.
What is voltage and its unit of measure?
The electrical force which causes current to flow in a circuit.
Measured in volts.
What is current and its unit of measure?
The movement of electrical charge through a circuit.
Measured in amperes. (A)
What is resistance and its unit of measure?
An opposition to the flow of electricity in a circuit. Controls the amount of voltage or amperage in a circuit.
Measured in ohms.
What is Hertz?
An electrical unit of frequency equal to one cycle per second. (Hz)
What is a bus?
A distribution point in an aircraft electrical system to which the battery and the generator(s) are connected.
How many generators are on the P-3C?
Four. Three engine-mounted generators on engines 2, 3, and 4. And APU.
On the P-3C, how is the engine reduction gear protected in case the generator seizes?
By a shear section on the generator stub shaft.
On the P-3C, when does the GEN OFF light indicator illuminate?
With any failure of any of the engine generators.
What is different about the APU generator as opposed to the engine mounted generators?
The APU generator has a cooling bell housing.
How is primary AC power provided on the P-8A?
Two engine driven generators. (IDG’s)
When do sensing relays energize?
When generator voltage and frequency are correct.
They are identical and interchangeable.
Where are the sensing relays located on the P-3C?
Located in the forward and main load centers.
What is the purpose of circuit breakers and what type are used in the electrical systems?
To protect the circuit.
Push-pull type.
