Electrical Installations

Question 1

What was the driving force for developing the low smoke family of cables?

Answer 1

The navy needed a new cable that would give off less toxic fumes and smoke during a fire

Question 2

Which of the following are classifications of cable types

Answer 2

Special purpose
Non flexing
Repeated flexing service

Question 3

What is the purpose of aluminum or steel covering of armored cable

Answer 3

To give physical protection to the cable sheath during installation

Question 4

What is the purpose of using non flexing cable

Answer 4

To use with permanent installations

Question 5

Flexing service cable designed for use aboard ship is commonly referred to as being portable because

Answer 5

It is principally used as leads to portable electric equipment

Question 6

Repeated flexing, general use-cable is categorized by what means?

Answer 6

The number of conductors in the cable

Question 7

If you see the symbol HOF on a cable designation you know the cable is of what type

Answer 7

Heat and oil resistant, flexible

Question 8

If you need to find a comprehensive listing of the requirements for installing cables aboard Navy ships, you should refer to what publication

Answer 8

General specifications for ships of the U.S. Navy, NAVSEA S9AAO-AA-SPN-010

Question 9

A cable has been constructed so that it provides added protection, allowing it to function for a longer period under fire conditions. What term describes this cable?

Answer 9

Circuit integrity

Question 10

What information is on the thin marker tape present on most cables and cords under the binder or jacket

Answer 10

Name and location of the manufacturer
The year the cord or cable was made
The MILSPEC number of the cord or cable

Question 11

When selecting a replacement cable for a particular installation, you must know all EXCEPT which of the following factors?

Answer 11

The number of bends in the cable

Question 12

Before choosing the size of the cable to use in a circuit installation, what information is necessary for you to know?

Answer 12

The total connected load current, the demand factor, and the allowable voltage drop

Question 13

Which if any of the following is the reason for keeping cable runs as short as possible?

Answer 13

To keep attenuation to a minimum

Question 14

What letters would be used to designate an emergency lighting circuit on a cable supplying 115 volts ac to a circuit with a load of 120 watts

Answer 14

EL

Question 15

You are installing new cables, you should measure the bend radius at what point on the cable?

Answer 15

On the innermost portion of the cable

Question 16

In what publication will you find the exact method to use when installing cables

Answer 16

Electronics installation and maintenance handbook (EIMB)

Question 17

What action should you take before you clamp a solder-type terminal to a conductor

Answer 17

Twist the strands tightly and solder them only

Question 18

A cable has been newly installed. What type of meter should you use to test the insulation resistance?

Answer 18

A megger

Question 19

Neutral polarity in a conductor is identified by what color?

Answer 19

White

Question 20

The marking system for power and lighting cables is shown in what sequence?

Answer 20

Source, voltage, service

Question 21

A cable marked as (1-120-2)-24-C(2) indicates that the circuit is supplying a maximum voltage of ?

Answer 21

24V

Question 22

A circuit marking if (4-168-1)-4P-A(1) indicates that the circuit is supplying (a) what voltage and (b) what type of power

Answer 22

450v

Ships service

Question 23

If you want cable to present a neat appearance and to be traced easily in equipment, you should take what action

Answer 23

Lace them together

Question 24

What is the primary purpose of cable maintenance

Answer 24

To preserve the insulation resistance

Question 25

Which of the following purposes is/are served by insulation on electric cables and equipment?

Answer 25

Isolating current-carrying conductors and conductive structural parts of other circuits or equipment Insulating points of unequal potential from one another

Question 26

Electrical insulating materials are classified according to what characteristic

Answer 26

Their temperature index

Question 27

Electrical insulating materials are classified according to what characteristic?

Answer 27

Their temperature index

Question 28

What type of insulation is impregnated cotton

Answer 28

Class A

Question 29

What class of insulation is quartz

Answer 29

Class C

Question 30

What class of insulation is paper

Answer 30

Class O

Question 31

What class of insulation is asbestos

Answer 31

Class B

Question 32

Shipboard lighting transformers in a 60-hertz circuit are constructed using what class insulation?

Answer 32

Class B

Question 33

What is the limiting temperature of a piece of equipment with class N insulation?

Answer 33

200degrees C

Question 34

You would use a monograph when taking what measurement

Answer 34

The resistance/foot of a cable

Question 35

If a cable has been energized for 6 hours, what temperature should the cable be assumed to be for purposes of heating resistance?

Answer 35

104F

Question 36

What is the size and designation for casualty power cables on ac power systems

Answer 36

LSTHOF-42

Question 37

Casualty power cable leads are color coded for identification. What are the proper colors for a,b, and c phases respectively

Answer 37

Black White Red

Question 38

To provide or install shore power to a ship requires which of the following equipment?

Answer 38

Shore power station and receptacle Connecting cable Cable plug

Question 39

The shore-power system is designed to provide enough power for all equipment normally energized while at sea

Answer 39

False

Question 40

You are connecting casualty power cables in a dark compartment. What conductor feature is identified by three separate servings of twine or o-rings

Answer 40

Phase C

Question 41

What type of cable is used to connect fixed terminals that penetrate decks and bulkheads

Answer 41

LSTSGU-75

Question 42

Shore power is supplied to the ship through the use of (a) what specific length of (b) what type of cable?

Answer 42

150ft | THOF-400

Question 43

You are testing the phase sequence of a shore connection. What is indicated by a clockwise rotation of the phase sequence indicator?

Answer 43

Correct phase sequence

Question 44

Kick pipes that penetrate wooden decks should be made from what material?

Answer 44

Aluminum

Question 45

Limit switches are installed so they are connected in what configuration with (a) the master switch and (b) the voltage supply circuit?

Answer 45

Series | Series

Question 46

What is a pilot device?

Answer 46

A small device that controls a large device

Question 47

A thermal overload relay is adjusted to trip at a predetermined value. What action can you take to vary the tripping current

Answer 47

Move the relay heater coil

Question 48

What type of protection is provided by reverse-power relays?

Answer 48

They protect the generators from damage by motoring prime movers

Question 49

When two or more dc generators are connected in parallel, what device disconnects a generator from the line if the generator starts drawing power from the line?

Answer 49

A reverse-current relay

Question 50

What is the closing sequence of the contacts in an ACB circuit breaker

Answer 50

Arcing contacts close; then the main contacts close

Question 51

The instantaneous trip setting of the AQB-A250 circuit breaker is adjusted by using what components?

Answer 51

Adjusting wheels

Question 52

Which of the following circuit breakers must be manually operated to interrupt current flow

Answer 52

Type NQB | type NLB

Question 53

Selective tripping is useful aboard ship for what reason?

Answer 53

It isolates faulty circuits without interrupting other associated circuits

Question 54

When testing a grounded receptacle, what is the max acceptable resistance from the ground connection to the ships hull

Answer 54

1.0 ohms