Module 9

Question 1

Electric circuits are protected from overheating by means of?

Answer 1

Fuses

Question 2

The three types of Circuit Protection devices most commonly used in aircraft circuits are?

Answer 2

Fuses,Circuit breakers, current limiters

Question 3

Aircraft fuse capacity is rated in?

Answer 3

Amps

Question 4

What is an important factor in selecting aircraft fuses?

Answer 4

The the capacity matches the circuit requirements

Question 5

A circuit protection device called a current limiter is essentially a slow blow fuse and is designed to be used in?

Answer 5

heavy power circuits

Question 6

What is the advantage of a current limiter?

Answer 6

It will accept overload for a certain amount of time

Question 7

A circuit breaker is installed in an aircraft electrical system primarily to protect the?

Answer 7

Circuit

Question 8

The circuit breaker in the the instrument lighting system protects the?

Answer 8

Wiring system from too much current.

Question 9

What is the advantage of a circuit breaker when compared to a fuse?

Answer 9

Resettable & reusable

Question 10

In aircraft electrical systems automatic reset circuit breakers?

Answer 10

Should not be used in circuit protection.

Question 11

A thermal switch or thermal protector as used in an electrical motor, is designed to:

Answer 11

open the circuit & protect the motor from overheating by allowing it to cool down.

Question 12

The normal rating of electrical switches refers to continuous _________ rating with the contacts _________

Answer 12

current, closed

Question 13

What is the purpose of the selection of De-rated switches for known continuous load current applications?

Answer 13

Better efficiency & longer life

Question 14

The navigation lights of some aircraft consist of a single circuit controlled by a single switch which has an On position and an Off position, with no additional positions possible. This switch would be referred to as a ?

Answer 14

Single pole, Single throw two position switch.

Question 15

What kind of switch should you install in a single wire circuit that required the switch to be manually held in the on position?

Answer 15

Single pole, single throw two position normally open switch

Question 16

A certain switch is described as a single-pole double-throw switch (SPDT). The “Throw” of a switch indicated the number of:

Answer 16

circuits each pole can complete through the switch.

Question 17

Circuits that must be operated only in an Emergency, or whose inadvertent activation could endanger a system, frequently employ?

Answer 17

Guarded switches

Question 18

An aircraft electrical circuit control relay is?

Answer 18

An electrically operated switch.

Question 19

A battery-generator system provides direct current, on installations requiring alternating current from the battery-generator system it is necessary to have?

Answer 19

An inverter

Question 20

Static inverters are electronic devices that change DC to AC with the use of

Answer 20

An oscillator

Question 21

The purpose of a rectifier in an electrical system is to change:

Answer 21

AC to DC

Question 22

Certain transport aircraft use AC electrical power for all normal operation and battery-furnished DC electrical power for standby emergency use. In aircraft of this type that operate no DC generators, the batteries are kept charged by

Answer 22

Rectifiers

Question 23

Aircraft which operate only AC generators (alternators) as a primary source of electrical power normally provide current suitable for battery charging through the use oF?

Answer 23

Stepdown transformer & rectifier

Question 24

A typical application for Zener diodes is?

Answer 24

As voltage regulators