AMT Aircraft Electrical Systems 3

Question 1

What is the function of a voltage regulator in an aircraft generator system?

Accepted Answer

To maintain constant generator output voltage under varying loads

Answer

The voltage regulator controls generator field current to maintain a steady output voltage regardless of electrical load or engine speed changes.

Question 2

When troubleshooting an open circuit, a voltmeter connected across the break will read:

Accepted Answer

Full system voltage

Answer

In an open circuit, the voltmeter reads full supply voltage across the break because no current flows and the entire EMF appears across the open point.

Question 3

Aircraft wiring AWG (American Wire Gauge) sizing is selected primarily based on:

Accepted Answer

The current load and allowable voltage drop over the wire length

Answer

Wire gauge must handle the circuit's current without overheating and keep voltage drop within acceptable limits for the length of the run.

Question 4

A reverse current cutout relay (or reverse current relay) in a DC generator system opens when:

Accepted Answer

Generator output falls below battery voltage causing reverse current flow

Answer

When generator voltage drops below battery voltage, current would flow backward from battery to generator; the relay opens to prevent this reverse flow and possible generator damage.

Question 5

Which of the following best describes a 'phantom load' in an aircraft electrical system?

Accepted Answer

A continuous small current drain from devices left energized when the master switch is off

Answer

Phantom (or parasitic) loads are small but continuous drains from clocks, memory circuits, or improperly wired equipment that can discharge the battery over time.

(AMT) Aviation Maintenance Technician Practice Test

(AMT) Aviation Maintenance Technician Practice Test

AMT Aircraft Electrical Systems 3