Electrical Systems Flashcards
What size generator must be used in an aircraft electrical system if the connected electrical load is 30 amps, and there is no way of monitoring the generator output?
When monitoring is not practical, the total continuously connected electrical load must be no more than 80% of the rated generator output. This would require a generator with a rating of 37.5 amps. Practically, a 40-amp generator would be installed.
What is meant by “flashing” the field of a generator?
Restoring the residual magnetism to the frame of the generator. This is done by passing battery current through the field coils in the direction it normally flows when the generator is operating.
What is meant by paralleling the generators in a multi-engine aircraft?
Adjusting the voltage regulators so all the generators share the electrical load equally.
What are the three types of voltage regulators used with aircraft generators?
Vibrator-type, carbon-pile type, and solid state-type.
How many electrical phases are in aircraft alternators?
Three.
What is the advantage of using AC power over DC power?
AC voltages can be stepped up to higher voltages, which means that current goes down and smaller wires can be used to save weight. The voltage is stepped back down at the point of use.
What is the frequency of AC voltage used in aircraft?
400 Hz.
What is a generator control unit (GCU)?
The GCU controls the output of AC alternator or generator.
