ET VOl 8 Support systems CH 1,3

Question 1

Three of the four methods of cooling are forced-air, air-to-air, air-to-liquid. What is the fourth?

Answer 1

convection

Question 2

When utilizing forced-air cooling, an air filter must be provided at the air outlet to remove dust and dirt from the exhaust air.

Answer 2

false

Question 3

Heat is removed from the air passing by the heat producing source in an air-to-air cooling system by forcing it through what component?

Answer 3

3. Heat exchanger

Question 4

Efficiency is increased in an airto- liquid cooling system by the use of what system component?

Answer 4

1. Liquid heat exchangers

Question 5

What number of basic cooling systems make up a typical liquid cooling system?

Answer 5

2

Question 6

The secondary cooling system transfers the heat load from the electronic equipment to the primary system.

Answer 6

true

Question 7

The Navy uses what number of basic configurations of liquid cooling systems?

Answer 7

3

Question 8

Which of the following water resources is/are used for primary cooling?

Answer 8

Seawater and chilled water

Question 9

The cooling water for the primary cooling system is either seawater or chilled water. The seawater is from the sea and the chilled water is from what source?

Answer 9

The ship’s air conditioning plant

Question 10

When temperature range is considered to be critical, what type of cooling system would most likely satisfy this need?

Answer 10

Type III (cw/dw heat exchanger with a cw/dw heat exchanger standby)

Question 11

What type of liquid cooling system can satisfactorily be operated when seawater temperatures reach 95°F?

Answer 11

TYpe I (sw/dw heat exchanger with sw/dw heat exchanger standby

Question 12

What is Type II Liquid cooling config?

Answer 12

SW/DW heat exchanger with CW/DW heat exchanger stby

Question 13

In a primary cooling system, flow regulator may be known by what other term?

Answer 13

4. Orifice plate

Question 14

Open looped seawater systems are also called one-pass because the seawater flows through the system only once.

Answer 14

true

Question 15

Secondary cooling systems are which of the following types?

Answer 15

Closed-loop only

Question 16

An expansion tank is installed in what system to compensate for changes in coolant volume?

Answer 16

3. The distilled water

Question 17

What term best describes a expansion tank that is located above the highest point in the secondary system and vented to the atmosphere

Answer 17

4. Gravity tank

Question 18

What term best describes an expansion tank that requires an air charge on the tank and is located below the highest point in the secondary cooling system?

Answer 18

Compression tank

Question 19

What definition best describes the word submicron?

Answer 19

Less than one millionth of a meter

Question 20

The Type II cooling system employs what configuration?

Answer 20

One SW/DW heat exchanger and one standby CW/DW heat exchanger

Question 21

The Type III cooling system employs what configuration?

Answer 21

One CW/DW heat exchanger and one standby CW/DW heat exchanger

Question 22

In a Type III cooling system, the two-way temperature regulating valve is used instead of a threeway valve to regulate the temperature in what system component(s)?

Answer 22

2. The secondary loop

Question 23

Heat exchanger

Answer 23

is constructed to be shell-type and tube-type in which the secondary coolant flows through the shell, while the primary coolant flows through the tubes.

Question 24

Flow regulators

Answer 24

It is used to provide a constant flow of coolant through the system

Question 25

Expansion tank

Answer 25

It maintains a positive pressure on the circulating pump inlet, compensates for changes in the coolant volume and it vents air from the system.

Question 26

Seawater strainer

Answer 26

It is used in the seawater cooling system to remove debris and sea life, which could clog the pressure and flow control devices.

Question 27

Temperature regulating valve

Answer 27

It regulates the amount of cooling water flowing through or bypassing a heat exchanger to maintain a desired temperature of distilled water going to the electronic equipment

Question 28

Circulating pump

Answer 28

It is used to circulate secondary distilled water

Question 29

Demineralize

Answer 29

It maintains the secondary cooling system’s purity

Question 30

An oxygen analyzer is used to measure the amount of dissolved oxygen in the liquid cooling system. The presence of oxygen causes oxidation within the cooling system.

Answer 30

true

Question 31

When inspecting a telltale drain, you discover that it is leaking. What failure does it indicate?

Answer 31

3. The tube joint

Question 32

The overall effectiveness of the heat exchanger is determined by comparing the primary inlet temperature to its outlet pressure. The result of this comparison is best described by what term?

Answer 32

Temperature gradient

Question 33

The device that is inserted in the heat exchanger’s water box to concentrate electrolytic action to it vice to the metal of the heat exchanger’s tubes is made of what material (s)?

Answer 33

2. Zincs only 3. Zinc anode only

Question 34

Who is the best qualified person on board to determine the overall condition of the cooling system?

Answer 34

1. Engineering officer

Question 35

The expansion tank sight glass should normally read in what range?

Answer 35

2/3 to 4/5 full

Question 36

The low-level alarm switch is usually set at 20 percent of tank capacity. The alarm will initially sound when the distilled water level reaches which of the following levels?

Answer 36

20%

Question 37

What term best describes the word makeup water?

Answer 37

1. Distilled water

Question 38

When, if ever, may potable water be used in electronic cooling systems?

Answer 38

never

Question 39

What is the maximum permissible chloride that may be used in cooling system water?

Answer 39

0.065 epm

Question 40

What is an indication that the 1-42. 1-43. 1-44. 1-45. 1-46. 1-47. duplex strainer is clogged?

Answer 40

The pressure reading will be 5 to 10 psi above the clean basket reading

Question 41

If the pressure drop is less than that of a clean basket reading, the basket may be missing.

Answer 41

true

Question 42

The three-way temperature regulating valve is used where seawater is the primary cooling medium, and the two-way valve is used where chilled water is the primary cooling medium.

Answer 42

true

Question 43

The basic operation of both the two-way temperature regulating valve is the same as the three-way temperature regulating valve except that the two-way valve has a manual override feature.

Answer 43

false both have manual override

Question 44

Temperature regulating valve corrective maintenance consists only of visual checks for leaks and corrosion.

Answer 44

false

Question 45

Which of the following devices is used to regulate flow in a seawater cooling system

Answer 45

3. The orifice plate

Question 46

Which of the following flow regulators is used to regulate flow in the chilled water system?

Answer 46

3. The variable orifice (constant Flow regulator)

Question 47

Which of the following devices would be used to protect a cooling system from over pressurization?

Answer 47

4. The relief valve

Question 48

What is the function of a typical low-flow switch?

Answer 48

1. To indicate low coolant flow

Question 49

In a venturi-type flowmeter, the flow rate is measured by what process?

Answer 49

1. The pressure differential

Question 50

Which of the following flowmeters allows visual inspection of the coolant for entrained air?

Answer 50

4. The rotameter-type

Question 51

Operating a circulating pump with insufficient coolant flow could cause which of the following malfunctions?

Answer 51

The overheating of the pump only 2. The seizure of the pump only

Question 52

What percent of the coolant flows through the demineralizer in one hour?

Answer 52

5%

Question 53

Which of the following demineralizer components is used to remove small particles from the coolant?

Answer 53

4. The submicron filter

Question 54

Which of the following contaminations is least likely to occur in a distilled water and ethylene glycol coolant system?

Answer 54

bacterial

Question 55

Demineralize performance and coolant purity is monitored by measuring what property of the coolant?

Answer 55

Conductivity

Question 56

Scheduled maintenance of a demineralizer consists primarily of performing what preventive action?

Answer 56

Replacing the filters and cartridges

Question 57

Which of the following contaminates could be considered a source of contamination for an oxygen analyzer sensor?

Answer 57

Oil from your fingers

Question 58

What position on an alarm switchboard is used for alarm acknowledgement?

Answer 58

standby

Question 59

What position on an alarm switchboard is used to simulate an alarm position?

Answer 59

test

Question 60

What is the first step in isolating the extent of waveguide flooding?

Answer 60

1. Secure the cooling system

Question 61

Which of the following systems comprises the shipboard power distribution system?

Answer 61

1. The casualty power system only 2. The emergency power system only 3. The ship’s service system only

Question 62

What is the function of the switchboard bus ties?

Answer 62

To permit switchboards to be cross connected and to allow paralleling of generators

Question 63

On small ships, centrally locating switchboards (with respect to the load) and feeding them directly from the generators have which of the following advantages?

Answer 63

1. It simplifies the installation 2. It reduces size and weight requirements 3. It reduces equipment requirements

Question 64

Circuit information plates are located on which of the following locations

Answer 64

The distribution panels and bus transfer equipment

Question 65

Why is the phase sequence important to the power distribution system aboard ship?

Answer 65

The phase sequence determines the direction of rotation of three-phase motors

Question 66

What service is provided by bus transfer equipment?

Answer 66

It provides two sources of power to vital ship’s equipment

Question 67

If NORMAL power were to fail supplying the HF transmitter, ALTERNATE power would be restored by the use of which of the following components?

Answer 67

Manual bus transfer (MBT) only

Question 68

Aboard ships, switchgear groups are physically separated as much as practical to achieve what objective?

Answer 68

Afford greater protection from battle damage

Question 69

Which of the following actions is NOT a function provided by switchboards aboard ships?

Answer 69

Automatic shifting of power to alternate sources if normal power is lost

Question 70

What is the purpose of disconnect 2-11. 2-12. 2-13. 2-14. links?

Answer 70

They provide isolation from one switchboard while repairs are being conducted on another

Question 71

The output of all ac generators is developed in what part of the generator?

Answer 71

The armature windings

Question 72

What are the two major assemblies of an ac generator?

Answer 72

Armature and fields

Question 73

Three-phase generators have singlephase windings located what number of degrees out of phase from the other windings?

Answer 73

120° out of phase with the other two windings

Question 74

The three-phase, four-wire, STAR connected power distribution system is also know by what other term?

Answer 74

Wye connected

Question 75

In a transformer, electrical energy is transferred from one circuit to another through which of the following actions?

Answer 75

Electromagnetic induction

Question 76

Energy in a transformer is always transferred without a change in frequency, but you can expect a change in which of the following attributes?

Answer 76

Current and voltage

Question 77

Which transformer winding is designated as the primary winding?

Answer 77

The one that receives energy from an ac source

Question 78

What are the two principle types of transformers?

Answer 78

1. Core and shell

Question 79

Most power supply transformers are designed to operate at frequencies of

Answer 79

50 to 60 HZ

Question 80

Transformers of higher frequencies are of smaller design and permit savings of weight and use of associated equipments.

Answer 80

true

Question 81

The use of varnish to insulate adjacent laminations in a transformer core helps minimize which of the following factors?

Answer 81

Hysteresis losses

Question 82

In transformer lead markings high voltage leads are marked H1, H2, H3, etc. The letter signifies high voltage, what does the number indicate?

Answer 82

The higher the number, the higher the voltage

Question 83

Transformer secondary lead markings are identified by which of the following letters?

Answer 83

X

Question 84

Which of the following types of equipment are used to supply 400 Hertz power to a transformer?

Answer 84

1. Motor-generator units (older) 2. Static converters (newer)

Question 85

What is the primary purpose of the casualty power system?

Answer 85

To make temporary connections to vital circuits

Question 86

Casualty power bulkhead terminals are permanently installed on opposite sides of bulkheads for what reason?

Answer 86

To transfer power through decks without loss of watertight integrity

Question 87

A portable cable used to rig ac casualty power can carry (a) what maximum amount of current and (b) for what maximum number of hours?

Answer 87

(a) 200 A (b) 4 hours

Question 88

Shore power connections aboard ship may be used to supply power to another ship alongside.

Answer 88

true

Question 89

When testing shore power cables, you should use which of following grounds as a shore ground resistance?

Answer 89

The ship’s hull or metal ext

Question 90

What is the key component of the phase-sequence indicator?

Answer 90

1. The three-phase induction motor