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5th Year, Week 2 (Motor Control 3, Intro to PLC) > Motor Control 3 > Flashcards

Flashcards in Motor Control 3 Deck (99)
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1

What are the 3 types of DC motors?

1.) Series
2.) Shunt
3.) Compound

2

How many SETS of contacts do DC motors utilize?

1 Set (2 Contacts)

3

Rheostats are ____ control devices, meaning a person has to be there to operate it.

Manual

4

How do Rheostats change motor speed?

By changing the amount of current to the armature. (To which it is usually wired in series)

5

____ are a safety feature for maintaining connection after motor speed has reached maximum.

Holding Coils

6

T/F: Contactor starting connects partial voltage when first connected.

False, full voltage is connected across the contacts.

7

____ are segments that cool and separate arcs. Usually 80% of the energy is absorbed.

Arc Chutes

8

A ____ creates a magnetic field that extinguishes the arcs.

Blowout Coil

9

What are 3 ways that drives are better than rheostats>

1.) No human required to operate
2.) Less power to operate
3.) Cheaper in the long run

10

Motor speed monitoring is done with what 2 devices?

1.) Tachometer
2.) Encoder

11

How do you reduce the speed of a DC motor?

Reduce Armature voltage

12

How do you increase the speed of a DC motor?

Reduce field winding voltage

13

What are the two parts of a DC drive?

1.) Power section
2.) Control section

14

How does the control section of a DC drive control motor speed?

By quickly switching to dictate how much of the power is delivered to the motor, and when.

15

___-loop control has motor characteristics pre-programmed into the controller.

Open-loop, which is cheaper.

16

____-loop control uses sensors to monitor motor characteristics, adjusting as needed.

Closed-loop

17

What are the two types of DC motor braking?
(Except for Friction Braking)

1.) Dynamic - Braking Resistors
2.) Regenerative - Back to power source

18

What is the most common analog range?

4-20mA

19

What are the two reasons that using 4-20mA is the most common analog range?

1.) Longer range (Current, no voltage drop)
2.) Less to no issues from electrical noise.

20

What are the three types of analog signals?

1.) Current (4-20mA)
2.) Voltage (0-5vDC, 1-5vDC)
3.) Pressure (3-15PSI)

21

A ____ converts a signal to one that is more usable by the device.

Signal Conditioner

22

Limit Alarms are also known as ____.

Level-Relays

23

How can you use a 1-5vDC device with a 4-20mA system ?

With a 250 Ohm Resistor.

24

A ____ converts one type of energy to another, usually for reading/signal purposes.

Transducer

25

What are the two parts of a transducer?

1.) Sensor
2.) Transmitter

26

What are the two types of temperature sensors that vary resistance with temperature?

1.) RTD
2.) Thermistor

27

What are the 2 types of temperature sensors that produce a small voltage when heated?

1.) Thermocouples
2.) Solid State Temperature Sensors

28

Wires coming off of a thermocouple must be as short as possible to mitigate voltage drop, so they are usually ran to a nearby ____.

Reference block.

29

What are the 3 Position Sensing devices?

1.) Linear Potentiometers
2.) Rotary Potentiometers
3.) LVDT (Movable Core)

30

What are the 6 Pressure Sensor types mentioned in the book?

1.) Deflection
2.) Differential
3.) Bourden Tube
4.) Piezoelectric
5.) Direct (Strain Gauge + Load Cell)
6.) Solid State

31

What are the 6 types of Flow sensors that the book mentions?

1.) Paddle Wheel
2.) Turbine
3.) Vortex
4.) Electromagnetic
5.) Ultrasonic
6.) Mass (Thermal + Coriolis)

32

A Vortex-type flow sensor contains a component called the ____ which contacts the liquid to create vortices, which are utilized for measuring flow.

Bluff-Body

33

Ultrasonic-type flow sensors utilize ____ in the fluid they are reading, for receiving sound waves back.

Particulates

34

Current Sinking, NPN or PNP?, switch on the positive or negative side?

Sinking = NPN = switches on the Negative side.

35

Current Sourcing, NPN or PNP?, switch on the positive or negative side?

Sourcing = PNP = switches on the positive side.

36

How is an AC/DC input module able to utilize AC power?

Because it has Reverse parallel diodes.

37

T/F: TTL input modules are heavy duty.

True

38

What are the 4 types of input modules?

1.) Current Sinking
2.) Current Sourcing
3.) AC/DC
4.) TTL

39

What are the 3 types of output modules?

1.) DC Output (Current sinking)
2.) AC Output (Uses Triacs)
3.) TTL

40

T/F: Grounds should go elsewhere other than the drive, so any possible fault current or ESD stays away from the boards.

True

41

What does ESD stand for?

Electrostatic Discharge

42

Most "smart" or Solid State devices have ____-diagnostic capabilities.

Self-diagnostic

43

____(s) give absolute control of a motor through modulation, use much less energy than older starting technologies and are cheaper in the long run

VFD's

44

T/F: VFD's allow control of motor speed, torque, direction, and stopping.

True

45

What are some things to consider when SELECTING a VFD for installation?

1.) Speed desired
2.) Torque
3.) Direction
4.) Stopping
5.) Horsepower Rating

46

The feedback loop from speed sensors is a(n) ____ type signal, and it cannot be run with power feeds to motor.

Analog

47

____(s) act like isolation transformers to mitigate harmonics put out by the VFD during the course of modulation.

Line reactors

48

T/F: It isn't important to consider power quality before installing a VFD.

False

49

____(s) protect the VFD from the elements and also protect personnel from coming into contact with energized parts.

Enclosures

50

T/F: Wiring connections aren't very important.

False

51

T/F: The motor must be grounded to the VFD's internal grounding terminal.

True

52

There are four main areas to check for issues when troubleshooting a VFD, what are they, in-order?

1.) Inputs
2.) Outputs
3.) Program
4.) Internal Components

53

A ____ is an industrial-grade computer, with one dedicated purpose or chore.

PLC

54

What is the most common programming language that is used with PLC's?

Ladder-Logic

55

In what ways are PLC's and PC's similar?

1.) Processors
2.) Memory
3.) Motherboard
4.) Expansion Slots

56

How are PLC's and PC's different?

PLC's are not pre-programmed, nor do they have removable storage media.

57

What are the three ways to program a PLC?

1.) PC
2.) Buttons on the unit
3.) Handheld programmer

58

What program does the Allen-Bradley SLC 500 'family' of PLC's operate on?

RS Logix500

59

____ PLC's aren't able to be modified, all inputs and outputs are already built in.

Stand-alone

60

T/F: The MicroLogix 1000 is a standalone unit.

True

61

The ____ is the box or cabinet that the rack (chassis) is mounted to.

Backplane

62

What is the metal rail that the processor/power supply and I/O modules are mounted on in a modular PLC system?

The Rack, or Chassis

63

What are the three types of OUTPUT signals?

1.) Analog
2.) Discrete
3.) Digital

64

T/F: Regular I/O modules can be used for stepper and servo motors.

False

65

____ manufacturing produces consumables such as food, gas, paint, paper, and chemicals.

Process manufacturing

66

____ manufacturing produces durable goods such as automobiles, fridges, and components used in larger and smaller products.

Discrete Parts Manufacturing

67

T/F: Synchronous motors have no slip.(After they are brought up to speed)

True

68

T/F: Induction motors are more expensive than synchronous motors.

False, synchronous are more expensive because they can be more precisely controlled.

69

____ motors are best suited for Direct Drive, High Horsepower, or Low RPM Loads.

Synchronous

70

What are the 2 phases of synchronous motor starting?

1.) Start-Up
2.) Attaining Synchronous Speed

71

____ motors use discrete inputs (Electronic Digital Pulses) to position the motor. This can be done clockwise or counter-clockwise with very precise control.

Stepper

72

What is stepping rate?

The maximum amount of steps in one second.

73

What is Step Angle?

The amount of rotation per pulse.

74

What is Holding torque?

The maximum load torque with the stator energized.

75

What is Detent Torque?

The maximum load torque with the stator de-energized.

76

A ____ is a motor similar to a stepper motor, but with a feedback loop for monitoring exactly how much the shaft has rotated, so corrections can be made.

Servo-motors.

77

A ____ Network is a group of locally connected machines in a company building or group of buildings.

Enterprise

78

A ____ is used as a data highway within an enterprise network.

LAN (Local Area Network)

79

A ____ network links branch offices and single mobile users to a local enterprise network or the internet.

Remote

80

A ____ network is comprised of connected enterprise networks.

Wide-Area

81

What are the 4 types of network cabling discussed in the book?

1.) UTP
2.) STP
3.) Coax
4.) Fiber

82

A ____ is a multiport repeater, similar to a signal booster

Hub

83

____ are also called "Network Media" and are the physical path on which electrical and optical signals travel.

Cables

84

____(s) are high power workstations with a specific purpose.

Servers

85

A ____ connects a device to the network.

Interface Card.

86

____(s) are devices such as printers, plotters, fax machines, and backup devices.

Peripherals

87

What is an HMI and what does it do?

Human-Machine-Interface, and it is the medium between human operators and the device/system. Displays system parameters and allows an operator to make changes.

88

What are 4 things to consider when selecting Network Media?

1.) Range
2.) Bandwidth
3.) Noise Immunity
4.) Cost

89

Unshielded Twisted Cable (UTP), which is used for most ethernet wiring, is divided into 6 different designations (ratings) what are they?

CAT3
CAT4
CAT5
CAT5E
CAT6
CAT7

90

What are the three Network Topologies?

1.) Bus - Central Network Media
2.) Ring - Connected in loop shape
3.) Star - One Central Cluster and hub.

91

Ethernet consists of what 3 parts?

1.) Physical Cable
2.) Network Rules
3.) Standard Data Packet

92

____ is a medium level control network for automation. It does NOT carry device power.

Control-Net

93

____ is the lowest level of base integration devices. It carries the device power in the same cable.

Device-Net

94

Cable ____(s) prevent the data in the cable from reflecting back off of the end points of the cable.

Terminators

95

What is the six step troubleshooting sequence?

1.) Define the Problem
2.) Decide what needs to be tested
3.) Decide what type of test should be performed
4.) Correct the Problem
5.) Verify Correct Operation
6.) Determine the cause of failure

96

____ diagrams use rectangles to identify parts of a system.

Block

97

Signal flow is divided into ____ and ____.

Power and Information

98

What are the 5 Line types in a block diagram?

1.) Linear
2.) Convergent
3.) Divergent
4.) Feedback
5.) Switched Path

99

____ is a four step method to work your way down to the issue.

Information Funneling