Aircraft Electrical Systems

Question 1

What controls the output voltage of an alternator ?

Answer 1

GCU (Generator Control Unit)

Question 2

How long should bonding jumper wires be ?

Answer 2

Short as possible but long enough to allow freedom of movement of the component

Question 3

What factors are considered when selecting wires size for electrical power ?

Answer 3

Voltage drop, system voltage, Wire length, current carrying and load continuous or interminent

Question 4

How can a particular wire in a bundle be identified ?

Answer 4

Identification code on the wire

Question 5

What tool would you use to determine the size of an unmarked wire ?

Answer 5

A wire guage

Question 6

What size electrical conduit should be used ?

Answer 6

25 % larger than the maximum diameter of the wire bundle

Question 7

What should be done to a conduit when fittings are not used ?

Answer 7

It should be deburred to prevent insulation damage

Question 8

What hardware is used to make bonding or grounding connections to a structure of dissimilar material ?

Answer 8

A washer of suitable material should be used so that corrosion will occur on the washer

Question 9

How many terminal lugs can be put on a single terminal strip stud ?

Answer 9

4

Question 10

When do DC motors draw several times their rated current ?

Answer 10

When starting

Question 11

When is a circuit breaker designed to open ?

Answer 11

When an overload or circuit fault exists, and before the wire emits smoke

Question 12

What type of circuit breaker should not be used in aircraft ?

Answer 12

Automatic reset

Question 13

What color is a left and right wing tip position light ?

Answer 13

Left - red / Right - green

Question 14

Where is the white position / navigation light mounted ?

Answer 14

On the tail, visible from the rear

Question 15

What could cause an AC electric motor to run too fast ?

Answer 15

Excessive applied VOLTAGE or shorted field windings

Question 16

What tool is used to check a motor or generator armature for shorts and opens under load conditions ?

Answer 16

Growler

Question 17

When using a growler, what indication will occur when a short exists between an armature segment ?

Answer 17

When a metal blade is held over the armature and short exists in a segment, the blade will being to vibrate and chatter

Question 18

How is the output voltage of an alternator controlled ?

Answer 18

By varying the field CURRENT that excites the alternator

Question 19

What instruments are used to monitor electrical systems loads ?

Answer 19

Ammeteres and voltmeters

Question 20

Why would it be necessary to analyze an electrical system before increasing the load on the system ?

Answer 20

To determine the generator capacity, wire size, and protective device capacity will not be exceeded

Question 21

Name several types of electrical devices that would be considered intermittent loads on an electrical system ?

Answer 21

Landing gear, cowl and wing flap motors, radio transmitters

Question 22

Under what condition must a switch be derated from its nominal rating ?

Answer 22

When used with inductive circuits, circuits with high in rush current, and with DC motors

Question 23

At what point in a circuit should the protective device be located ?

Answer 23

As close to the source as possible

Question 24

What could cause an AC electric motor to run too slowly ?

Answer 24

Lack of lubrication, defective wiring or low voltage

Question 25

Prior to making a continuity check, what must be done to an electrical circuit ?

Answer 25

Power must be turned off