Airframe - AM.II.K.K5 - Voltage regulators and over-volt and overcurrent protection

Question 1

What is meant by a trip free circuit breaker?

Answer 1

A circuit breaker that cannot be closed while a fault exists, regardless of the position of the operating handle

Question 2

What is meant by a slow burn fuse?

Answer 2

A fuse that will allow more current than its rating to flow for a short period of time, bit will open the circuit if more than its rated current continues to flow

Question 3

What is the function of the of a fuse or circuit breaker in an aircraft electrical circuit?

Answer 3

• It protects the wiring from an excess of current
• It will open the circuit if enough current flows to heat the wire

Question 4

What are two principles upon which circuit breakers operate?

Answer 4

• magnetic circuit breakers open a circuit when the current creates a strong enough magnetic field
• thermal circuit breakers open a circuit when the current causes enough heat

Question 5

What circuit in an aircraft electrical system is not required to have a circuit protective device?

Answer 5

the main current for starter motors, used during starting only

Question 6

Is an automatic reset circuit breaker approved for aircraft electrical circuits?

Answer 6

No, a manual operation is needed to restore service after the circuit breaker has tripped

Question 7

How does a vibrator type voltage regulator maintain a constant voltage?

Answer 7

• When the voltage rises above the desired value, an electromagnetic relay opens and inserts a resistor in the generator field circuit
• this decreases the field current and lowers the generator output voltage

Question 8

What two components are normally houses with a vibrator voltage regulator in a single unit generator control?

Answer 8

A current limiter and a reverse current cutout relay