Final Practice Flashcards

1
Q

Proper ground conductors must be of a sufficient gauge to carry any _______, which may be imposed upon it.________

A

current, currents

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

Grounding protects automation systems from what four(4) potential damages?

A)operator system error

B) voltage fluctuations

C) loss of voltage

D) surges

E) short circuits

F) lighting

G) Power system harmonics

A

B) voltage fluctuations

D) surges

E) short circuits

F) lighting

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

Braided outer conductors or metal foil wrapped around 2 conductors in a signal line are called

A

(shields, shielding)

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

Instrumentation wires come in twisted pairs. One wire is black and the other is White. For DC electrical circuits, the following colour-coding designation is used for Polarity. (the majority of time!)

Match

White wires

Green wires

Black wires

  1. are designated to have positive polarity in DC circuits
  2. designated to have negative polarity in DC circuits
  3. are designated to be connected to ground in DC circuits (no polarity).
A

White wires are designated to have positive polarity in DC circuits

Green wires are designated to be connected to ground in DC circuits (no polarity).

Black wires designated to have negative polarity in DC circuits

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

The function of any grounding system is, therefore, to bring the voltages on all circuits within a system to the same reference or common point

A) True
 	B) False
A

A) True

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

Multi-strand wires are the most common type of conductor in use in industry today.

A) True
 	B) False
A

A) True

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

A Megger device is basically a small high voltage generator.

The Megger generates relatively high voltages in amounts of 1000V

A) True
 	B) False
A

A) True

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

In general, effective grounding means:
A) The path to ground is continuous & permanent

B) be of sufficient capacity and made of aluminum

C) Any and all terminals on the ground system must be corrosion-free and tight, to avoid resistance at the terminal junctions

D) Terminated in a control room or enclosed wire way

A

A) The path to ground is continuous & permanent

C) Any and all terminals on the ground system must be corrosion-free and tight, to avoid resistance at the terminal junctions

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

The two types of coupling that exist are________and ________

A

(inductive, capacitive)

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

Usually the frame of an electrical device is a reference point, where all the circuits of the device eventually connect together

A

Chassis Ground (Common)

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

Is simply a point in a series of circuits where a common reference can be found.

A

System Common

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

common reference point where all circuits will lead to an earth-body connection.

A

Earth Ground

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

Usually caused by the double grounding of the neutral conductor in a system.

A

Ground Loops

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

Is a conductor, provided to ensure electrical continuity in any metallic non-current-carrying parts of electrical equipment

A

Bonding Conductor

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

Used to keep non-current carrying equipment equi-potential to each other

A

Bonding Jumper

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

noise introduced into circuits through conductors, and caused by switching transients

A

Conducted Noise

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

noise produced by communication radios, etc.

A

Radiated (Plane Wave) Noise

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

noice introduced into a system via electromagnetic field induction (capacitive or inductive).

A

Coupled Noise

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

Improper grounding of intrinsically safe barriers in IS applications. Depending on the application and model, some of these units shouldn’t be grounded!

    A) True
 	B) False
A

A) True

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

Instrumentation cabling and equipment is shielded to prevent accidental shock to personal.

A) True

B) False
A

B) False

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

Which of the following statements is true for a delta-connected three-phase system?
A) Phase voltage is higher than line voltage by a factor of 1.732
B) Line voltage is less than phase voltage by a factor of 1.732
C) Line voltage and phase voltage are the same
D) Line voltage is higher than phase voltage by a factor of 1.732

A

C) Line voltage and phase voltage are the same

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

A three-phase load has a phase voltage of 240V and a phase current of 18A. What is the apparent power of this load?

A) 22,449VA
B) 12,960 VA
C) 4320 VA
D) 7483 VA

A

B) 12,960 VA

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

An alternator with a line voltage of 2400V supplies a delta-connected load.The line current supplied to the load is 40A. Assuming the load is a balanced three-phase load, what is the impedance of each phase?

A) 26.4 ohms
B) 103.9 ohms
C) 34.7 ohms
D) 60 ohms

A

B) 103.9 ohms

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

Which of the following statements is true for a wye-connected three-phase system?

A) Line voltage is higher than phase voltage by a factor of 1.732
B) Phase voltage is higher than line voltage by a factor of 1.732
C) Line voltage and phase voltage are the same
D) Line voltage is less than phase voltage by a factor of 1.732

A

A) Line voltage is higher than phase voltage by a factor of 1.732

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

A delta-connected alternator is connected to a wye-connected resistive load. The alternator produces a line voltage of 240V and the resistors have a value of 6 ohms each.
Find

  • True Power
  • Line current to the load
  • phase voltage of the load
A
  1. 6V
  2. 1 A

9600 watts

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

A three-phase wye-connected load is connected to a 480V three-phase line. The line current to the load is 36A. If this load is pure resistive, what is total amount of power being used in this circuit?

A

29,929 watts

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

How many degrees out of phase are the voltages of a three-phase system?

A

120 deg

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

Which of the following statements is true for a delta-connected three-phase system?

A) Phase current is higher than line current by a factor of 1.732
B) Line current is higher than phase current by a factor of 1.732
C) Line current and phase current are the same
D) Line current is less than phase current by a factor of 1.732

A

B) Line current is higher than phase current by a factor of 1.732

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

A delta-connected three-phase load is connected to a 560V line.

The loads have an impedance of 14 ohms per phase. What is the apparent power of this connection?

A

67,200 VA

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

A delta connection has 30A of current flowing through each phase winding. How much current is flowing through each of the lines supplying power to the load?

A

52A

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

The windings of a three-phase alternator are connected delta. The alternator is producing a line-to-line voltage of 480V. What is the voltage across the phase windings?

A

480 V

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

An alternator with a line voltage of 2400V supplies a delta-connected load.

The line current supplied to the load is 40A.

Assuming the load is a balanced three-phase load, what is the impedance of each phase?

A

103.9 ohms

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

A wye-connected load has voltage of 600V applied to it. What is the voltage applied across each phase?

A

347V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

A three-phase alternator supplies power to a delta-connected resistive load. The alternator has a line voltage of 480V and each resistor of the delta load has 8 ohms of resistance.

Find:
I phase of load
I line
E phase

A

I Line (load) = 103.92A

E phase (load) = 480V

I Phase (load) = 60A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

A hazardous location is classified as a Zone 2 if flammable vapors are present less than _____ hrs per year.

A

10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Intrincisally Safe ( IS) wiring and grounding must comply with the following:
A) use only one ground
B) wiring must be placed in a separte panel
C) be separate from power and other cables
D) R of ground > 1 ohm
E) colored light blue
F) Ground wire must be at least 12 AWG and insulated except at the connection point

A

B) wiring must be placed in a separte panel

C) be separate from power and other cables

E) colored light blue

F) Ground wire must be at least 12 AWG and insulated except at the connection point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Seals are required when conduit crosses and area classification boundary.

A) True
 	B) False
A

A) True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

The two factors which define the explosive properties of a particular gas in CEC groups are:
A) pressure and temperature
B) degree of corrosiveness and water content
C) temperature and volume displaced
D) pressure and explosive wave propagation rate

A

A) pressure and temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q
What is the Act called that is a comprehensive legistlative framework for public safety in the Province of Alberta?
A) The Building Code
B) The Regulations Act
C) The Provincial Fire Code
D) The Safety Codes Act
A

D) The Safety Codes Act

40
Q

Protection by design and unable to ignite combutible materials, under normal or fault conditons is called

A

Intrinsically Safe

41
Q

Conduit and cable seals are designed to operate under process pressure conditions.

A) True

B) False
42
Q

An Explosion Proof enclosure means:
A) Enclosure designed to trap gas or vapors and allow them to be safely vented to atmosphere.
B) Enclosure that prevents an internal explosion from occuring in the first place.
C) Enclosure designed to withstand an internal explosion withour rupture
D) Enclosure that, if opened, will allow gas or vapors to escape

A

C) Enclosure designed to withstand an internal explosion withour rupture

43
Q
A calibration performed on an active system is called a(n):
A) bench calibration
B) in situ bench calibration 
C) lab traceable calibration
D) in situ field calibration
A

D) in situ field calibration

44
Q

What one safety issue should be highlighted when performing field calibrations on electrical equipment?

A) mistaking a high voltage area for a low voltage area during calibration.
B) ensure you are calibrating the correct instrument
C) performing a calibration when the process is not completely de-energized.
D) performing the calibation when not required to do so.

A

A) mistaking a high voltage area for a low voltage area during calibration.

45
Q

Threaded joints on covers and conduit entries in an Explosion Proof enclosure, is considered:
A) a tortuous path to reduce the energy of gas when flowing into an enclosure
B) a path of no gas flow at all.
C) an easy path to vent gases
D) a strong mechanical joint to ensure that the enclosure remains immovable

A

A) a tortuous path to reduce the energy of gas when flowing into an enclosure

46
Q

The main component used in a barrier protected in an IS system is the fuse.

A) True

B) False
47
Q

All electrical equipment used in hazardous locations must consist of a certification mark.

A) True
 	B) False
48
Q

Symbols for

  1. Intrinsically Safe
  2. Increased Safety
  3. Oil Immersed
  4. Pressurized
  5. Powder filled
  6. Encapsulation
  7. Non-Incendive
  8. Special Protection
A

Symbols for

  1. Intrinsically Safe i ia ib
  2. Flame Proof d
  3. Increased Safety e
  4. Oil Immersed o
  5. Pressurized p
  6. Powder filled q
  7. Encapsulation m
  8. Non-Incendive n
  9. Special Protection s
49
Q

“p” protection is where a purge or pressurization is applied to an enclosure to prevent explosive gases from entering the enclosure.

A) True
 	B) False
50
Q

Class II, Division I are areas described as follows:
A) an area where there is a hazardous area containing combustible fibers in active manufacturing
B) an area where there is a hazardous area containing combustible dusts under normal operating conditions
C) an area where there is a hazardous area containing combustible dusts under abnormal operating conditions
D) an area where there is a hazardous area containing combustible fibers in storage.

A

B) an area where there is a hazardous area containing combustible dusts under normal operating conditions

51
Q

Class 1 further divides into three zones; which are determined by:
A) frequency and duration of exposure to explosive gas
B) whether or not the area is ventilated
C) area and location of a particular part of a plant
D) the type of group that is present

A

A) frequency and duration of exposure to explosive gas
B) whether or not the area is ventilated
C) area and location of a particular part of a plant

52
Q

As an instrumentation technician/technologist you are allowed to install power wiring.

A) True

B) False
53
Q

A grain elevator would be classed as a:

A) class 2 enviroment
B) class 1 enviroment
C) class 3 enviroment
D) non-hazrdous enviroment
A

A) class 2 enviroment

54
Q

Install only essential electrical equipment in hazardous areas.

A) True
 	B) False
55
Q

Equipment that under normal operation is incapable of igniting gases or vapors are called:

A) Positive Ventilation
B) Explosion Prrof
C) Non-Incendive
D) Instrincially Safe

A

C) Non-Incendive

56
Q
If the concentration range for methane is 5% to 17 % by volume, then 5% by volume of methane is considered to be:
A) 100% UEL
B) 0% UEL
C) 100% LEL
D) 0% LEL
A

C) 100% LEL

57
Q

A Class I location is identified as Zone 1 if flammable gasses or vapors occur in normal operation.

A) True
 	B) False
58
Q

Gas groups are divided into 2 main areas:

A) mining and surface industries
B) Acetylene and all other gases
C) A and B
D) Class I and Class II

A

A) mining and surface industries

59
Q

The CEC applies to all jurisdictions in Canada.

A) True
 	B) False
60
Q

In Canada, all new installations must conform to the new Zone system

A) True
 	B) False
61
Q

If your facility is classified under the old Division system, then you can continue using that system, even when adding new additions to the installation.

A) True
 	B) False
62
Q

As an Instrumentaiton Technician/technologist, you are allowed to install and terminate electrical connections to measurment and control equipment.
A) True
B) False

63
Q
Identify the hazardous class for the following materials:
rayon fibers
grain dust	
gasoline	
wood shavings	
cotton
aluminum dust
flammable paint and solvents	
acetylene
A
rayon fibers  3
grain dust  2
gasoline  1
wood shavings  3
cotton  3
aluminum dust  2
flammable paint and solvents  1
acetylene  1
64
Q

Select the following statements that describe Explosion Proof equipment.
A) Protect covers from damage when off.
B) Five thread engagments on covers
C) Keep threads and flat surfaces clean
D) De-energize circuits before removing covers
E) Use lugs to tighten covers.
F) All threads must be lubricated

A

A) Protect covers from damage when off.
C) Keep threads and flat surfaces clean
D) De-energize circuits before removing covers

65
Q

A Safety Codes officer requires a warrant to enter a jobsite in order to carry out an inspeciton for the purpose of ensuring the Act is being complied with.
A) True
B) False

66
Q
Which zone has the highest hazard level?
A) Divison 1, Zone 0
B) Divison 2, Zone 0
C) Division 1, Zone 2
D) Division 1, Zone 1
A

A) Divison 1, Zone 0

67
Q
Class 1 are hazardous because of:
A) coal dust
B) gases and vapors
C) flyings and metal particles
D) grain dusts and powders
A

B) gases and vapors

68
Q

The aim of pressurization is change the area classification from Zone 1 to Zone 2 or Zone 2 to Non-Hazardous..
A) True
B) False

69
Q

A synchronous motor is an induction motor
A) True
B) False

70
Q

The ________in a D.C. generator, changes the AC produced in the armature into D.C.

A

COMMUTATOR

71
Q
What type of motor was the first to be invented?
A) single phase A.C. motor
B) D.C. generator
C) D.C. motor
D) A.C. generator
A

C) D.C. motor

72
Q

Alternators operate on the same principle of electromagnetic inductions as D.C. generators, but they
A) don’t require a magnetic field needed to achieve an output voltage
B) have armature conductors rotate outside the magnetic field
C) have no commutator to change the AC produced in the armature into D.C
D) have no Rotor that actually spins

A

C) have no commutator to change the AC produced in the armature into D.C

73
Q

A voltage induced in the armature windings that opposes the applied voltage in known as ________)electro-motive force

74
Q
The entire North American continent is powered by A.C. generators connected 
A) individually in series
B) individually in parallel
C) together in series
D) together in parallel
A

D) together in parallel

75
Q

The principle of operation of all three-phase motors is a Rotating magnetic field!
A) True
B) False

76
Q

The function of the commutator in a D.C. motor is to act as a ________switch to keep the current flowing in the proper direction through the armature.

77
Q

Most of the electric power in the world today is produced by A.C. Generators or ________

A

Alternators

78
Q

The three basic types of three-phase motors: 1st is the Squirrel-________motor. Then the ________-rotor motor. And finally the one that runs at constant speed is referred to as the ________

A

cage
Wound
synchronous

79
Q

The position at which there is no induced voltage in the armature of a D.C. generator is called the Neutral ________

80
Q

What two (2) factors determine the amount of Torque developed by a D.C. motor?
A) type of commutator used in the machine
B) What the Pole pieces are made of
C) The strength of the magnetic field of the armature
D) The strength of the magnetic field of the pole pieces

A

C) The strength of the magnetic field of the armature

D) The strength of the magnetic field of the pole pieces

81
Q

The principle of operation of a D.C. motor is Attraction and ______of magnetism.

82
Q

The ______are used to make contact with the commutator[IN A D.C. MACHINE] and to carry the output current to the outside circuit.

83
Q
The Armature marking on a D.C. generator are labeled
A) F1 & F2
B) no markings
C) A1 & A2
D) S1 & S2
A

C) A1 & A2

84
Q

The three factors that cause the magnetic field to rotate are:

  1. The three voltages are 120 degrees out of phase
  2. The arrangement of the stator windings
  3. The voltages ______polarity at regular intervals.
85
Q

What is a “synchronous speed”?
A) The speed of the rotation rotor
B) speed of cutting action of rotor
C) the speed on the nameplate of a motor.
D) The speed of the rotating magnetic field

A

D) The speed of the rotating magnetic field

86
Q

The output voltage of a 3 phase alternator is controlled by the amount of D.C. ______current.

A

excitation

87
Q

A rotating armature always produces A.C. voltage

A) True
 	B) False
88
Q

The TORQUE produced by an induction motor is based on 3 attributes:

  1. The strength of magnetic field of the rotor
  2. The strength of magnetic field of the stator
  3. The ______difference between rotor and stator flux.
A

phase angle

89
Q
What frequency should be applied to a six-pole motor to produce a synchronous speed of 400 RPM?
A) 80 Hz
B) 20 Hz
C) 40 Hz
D) 60 Hz
A

B) 20 Hz

f = [6 x 400Hz]/120

90
Q

Calculate the number of turns needed in the secondary winding of a transformer to transform a primary voltage of 300 volts down to a secondary voltage of 180 volts, if the primary winding has 1150 turns of wire.

91
Q

What are common efficiencies of transformers?

A

90 to 99 %

92
Q

Laminated cores are preferred because ________

A

A)

lamination acts as an insulator to reduce eddy currents

93
Q

When you use a Step-down transformer the current on the primary side will always be ____________ the secondary current!

94
Q

The most common type of control transformer uses what configuration?

A

two primary and one secondary winding

95
Q

What is an Auto-transformer?

A

A transformer that has only one winding for both primary and secondary

96
Q

Center-tapped Transformers have what is referred to as a Neutral conductor. This conductor will carry the

A

Sum of the unbalanced load

97
Q

The ability of one coil to induce a voltage into another coil is referred to as______

A

mutual induction