Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

NEETS > NEETS 15 ch 1,4 > Flashcards

NEETS 15 ch 1,4 Flashcards

1
Q

What is the name given to a variety of rotary electromechanical, position sensing devices?

A

The synchro

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the primary purpose of a synchro system?

A

Precise and rapid transmission of data between equipment and stations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name the two general classifications of synchro systems.

A

Torque and control.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the difference between a torque synchro and a control synchro?

A

A torque synchro is used for light loads and a control synchro is used in systems desired to move
heavy loads.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Using table 1-1, name two synchros that provide a mechanical output.

A

The torque receiver (TR) and the torque differential receiver (TDR).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does the code 26V-11TX4D mean on a synchro nameplate?

A

It is the third modification of a 26-volt 400-hertz (torque) synchro transmitter whose bodydiameter is between 1.01 and 1.10 inches.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which of the two synchro designation codes is indicated by 5DG on a synchro nameplate?

A

The Navy prestandard designation code.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

On the synchro schematic symbol, what indicates the angular displacement of the rotor?

A

The position of the arrow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two major components of a synchro?

A

The rotor and the stator.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which of the two main types of rotors can have either a single winding or three Y-connected
windings?

A

The drum or wound rotor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does the stator receive its voltage?

A

By the magnetic coupling from the rotor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where are the external connections made on standard synchros?

A

At the terminal board

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What major factors determine the load capacity of a torque-synchro transmitter?

A

. The number and type of synchro receivers, the mechanical loads on these receivers and the
operating temperatures of both the transmitter and receivers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Define the term “torque.”

A

A measure of how much load a machine can turn.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What unit of measurement refers to the torque of a synchro transmitter?

A

Ounce-inches.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of equipment normally uses 26-volt 400-hertz synchros?

A

. Aircraft.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When will a synchro generate more heat than it is designed to handle?

A

When it is overloaded.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How do synchros differ from conventional transformers?

A

Synchros have one primary winding that can be turned through 360º and three secondary
windings spaced 120º apart.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe the zero-position of a synchro transmitter.

A

The transmitter is in its zero-position when the rotor is aligned with the S2 stator winding.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When is the maximum voltage induced into a stator coil?

A

. When the rotor coil is aligned with the stator coil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What three factors determine the amplitude of the voltage induced into a stator winding?

A

The amplitude of the primary voltage, the turns ratio, and the angular displacement between the
rotor and the stator winding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the physical difference between a synchro transmitter and a synchro receiver?

A

A synchro receiver uses some form of damping to retard excessive oscillations or spinning.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What method is used to prevent oscillations in large synchro units?

A

Mechanical damping.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What two components make up a simple synchro transmission system?

A

A synchro transmitter and a synchro receiver.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What leads in a simple synchro system are connected to the ac power line?

A

The rotor leads.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the relationship between the transmitter and receiver stator voltages when their rotors
are in correspondence?

A

The voltages are equal and oppose each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the name given to the angle through which a transmitters rotor is mechanically rotated?

A

Signal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What two receiver leads are reversed to reverse the rotor’s direction of rotation?

A

. 1 and S3.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the most likely problem if the transmitter shaft reads 0º when the receiver shaft indicates
180º?

A

. The rotor leads on either the transmitter or the receiver are reversed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the purpose of using differential synchros instead of regular synchros?

A

. Differential synchros can handle more signals than regular synchros and also perform addition
and subtraction functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the two types of differential synchros?

A

The TDX and the TDR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Other than their physical differences, what is the major difference between a TDX and a TDR?

A

Their application: a TDX has one electrical and one mechanical input with an electrical output.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What determines whether a differential synchro adds or subtracts?

A

The way the differential synchro is connected in a system is the deciding factor on whether the
unit adds or subtracts its inputs

34
Q

In a TDX system when does the TR rotor follow the TX rotor exactly?

A

When the TDX rotor is on 0º.

35
Q

What is the angular position of a TX rotor when it is pointing toward the S1 winding? (Hint.
Remember synchros are labeled counter clockwise from 0º.

A

240º.

36
Q

In a TDX system with standard synchro connections, the TX rotor is at 120º and the TDX rotor is
at 40º. What position will the TR indicate?

A

. 80º.

37
Q

What connections in a TDX system are reversed to set up the system for addition?

A

The S1 and S3 leads are reversed between the TX and the TDX, and the R1 and R3 leads are
reversed between the TDX rotor and the TR.

38
Q

What connections in a TDR system are reversed to set up the system for addition?

A

The R1 and R3 leads between the TDR rotor and the TX to which it is connected

39
Q

In a TDR system connected for addition in what direction will the TDR rotor field turn when the
TX rotor to which it is connected turns counterclockwise?

A

Clockwise.

40
Q

What type of synchro is used in systems requiring large amounts of power and a high degree of
accuracy?

A

A control synchro

41
Q

What are the three types of control synchros?

A

. CX, CT, and CDX.

42
Q

How do the CX and CDX differ from the TX and TDX?

A

. The CX and CDX have higher impedance windings

43
Q

What three things prevent a CT rotor from turning when voltages are applied to its stator
windings?

A

The rotor is specially wound, it is never connected to an ac supply, and its output is always
applied to a high-impedance load

44
Q

When a CT is on electrical zero, what is the relationship between its rotor and the S2 winding?

A

They are perpendicular to each other

45
Q

What is the amplitude and voltage induced into the rotor when the CX is turned 90º while the CT
remains on electrical zero?

A

The voltage is maximum and in phase with the ac excitation voltage to the CX.

46
Q

What is the name given to the electrical output of a CT?

A

Error signal.

47
Q

In a control synchro system, when is the output of the CT reduced to zero?

A

When the CX and CT rotors are in correspondence.

48
Q

What is the purpose of the synchro capacitor?

A

To improve overall synchro system accuracy by reducing stator currents

49
Q

What type of synchros usually require the use of synchro capacitors?

A

TDXs, CDXs, and Cts.

50
Q

What type of current is eliminated by synchro capacitors?

A

Magnetizing current.

51
Q

How are synchro capacitors connected in a circuit?

A

They are delta-connected across the stator windings

52
Q

Why are synchro capacitors placed physically close to differentials transmitters and CTs?

A

To keep the connections as short as possible in order to maintain system.

53
Q

What is the name given to the synchro system that transmits data at two different speeds?

A

A dual or double-speed synchro system.

54
Q

What is the main reason for using a multispeed synchro system instead of a single-speed synchro
system?

A

. Greater accuracy without the loss of self-synchronous operation.

55
Q

In a dual-speed synchro system what determines the two specific speeds at which the data will be
transmitted?

A

The gear ratio between the two transmitters.

56
Q

What type of synchro system is used to transmit very large quantities?

A

A tri-speed synchro system

57
Q

What is the disadvantage of using a double receiver instead of two individual receivers?

A

If one of the receivers goes bad the entire unit must be replaced

58
Q

What is the purpose of “stickoff voltage”?

A

It is used in synchro systems to prevent false synchronizations

59
Q

What is the reference point for alignment of all synchro units?

A

Electrical zero.

60
Q

What is the most accurate method of zeroing a synchro?

A

The voltmeter method.

61
Q

What is the purpose of the coarse setting of a synchro?

A

.It ensures the synchro is on 0º, not 180º

62
Q

When is a synchro receiver (TR) properly zeroed?

A

A TR is zeroed when electrical zero voltages exist across its stator windings at the same time its
rotor is on zero or on its mechanical reference position

63
Q

What should a voltmeter read when a TX is set on coarse zero?

A

Approximately 37 volts

64
Q

What precaution should you take when you use 115 volts to zero a differential?

A

Never leave the circuit energized for more than 2 minutes

65
Q

Why should a synchro be rechecked for zero after it is clamped down?

A

. To ensure that it did not move off zero while it was being clamped

66
Q

What is the output voltage of a CT when it is set on electrical zero?

A

Zero or minimum voltage.

67
Q

When you zero a multispeed synchro system which synchro should you zero first?

A

. The coarse synchro

68
Q

What method of zeroing a synchro is perhaps the fastest but NOT necessarily the most accurate?

A

The electrical lock method

69
Q

What restrictions are placed on the use of the electrical lock method?

A

It can be used only if the leads of the synchro are accessible and the rotor is free to turn.

70
Q

When you zero a synchro with a synchro tester, what is indicated by a jump in the synchro tester’s
dial when the S1 and S3 leads are momentarily shorted?

A

. The synchro under test is not on electrical zero

71
Q

What should you do with a synchro that has a bad set of bearings?

A

Replace it.

72
Q

Name two types of trouble you would expect to find in a newly installed synchro system.

A

Improper wiring and misalignment

73
Q

What type of indicator is usually placed in the stator circuit of a torque synchro system?

A

An overload indicator.

74
Q

What is the most probable cause of trouble in a synchro system that has all of its receivers
reading incorrectly?

A

The transmitter or main bus

75
Q

If an ac voltmeter is connected between the S2 and S3 windings on a TX, at what two rotor
positions should the voltmeter read maximum voltage?

A

150º and 330º

76
Q

What precaution should you take when substituting a synchro tester in a circuit for a transmitter?

A

Use only one receiver so as not to overload the tester.

77
Q

What is a servo?

A

Direction of rotation and amount of torque.

78
Q

Compare the power sources of synchros and step-transmission systems.

A

Synchros use ac; step transmission uses dc.

79
Q

A step transmitter is a modification of what electrical device?

A

Rotary switch

80
Q

What type of mathematical problem is solved by resolvers?

A

Right-triangle, or trigonometric, problems.

NEETS (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions