ELE1510: FINAL EXAM TEST NOTES

Pataasin ang iyong marka sa homework at exams ngayon gamit ang Quizwiz!

4

?. Connect cable connector to box with locknut. (What stage is this in the BX Armour Cable Installation)

2

?. Insert insulating bushing to protect wire. Strip 1" of insulation with proper tools. (What stage is this in the BX Armour Cable Installation)

3

?. Install special BX connector snuggly onto armour cover. (What stage is this in the BX Armour Cable Installation)

1

?. Use Hacksaw to cut 6" of armour covering. Ensure insulation is not cut. (What stage is this in the BX Armour Cable Installation)

A

A 14 gauge wire is thicker in diameter than an 18 gauge wire? A. TRUE B. FALSE

b

A 50 VA transformer with a primary voltage of 120 volts and a secondary voltage of 24 volts has an available current on the secondary side of: a. 0.42 amps b. 2.08 amps c. 2.4 amps d. 0.48 amps

Series-Parallel Circuit

A circuit in which some of the circuit components are connected in series and others are connected in parallel.

Parallel Circuit

A circuit in which there are multiple paths for electricity to flow. Each load connected in a separate path receives the full circuit voltage, and the total circuit current is equal to the sum of the individual branch currents.

Series Circuit

A circuit in which there is only one path for electricity to flow. All of the current in the circuit must flow through all of the loads.

Fuse

A circuit interrupting device consisting of a strip of wire that melts and breaks an electric circuit if the current exceeds a safe level. To restore service, the fuse must be replaced using a similar fuse with the same size and rating after correcting the cause of failure.

Circuit

A closed path in which electrons from a voltage or current source flow. Circuits can be in series, parallel, or in any combination of the two.

Inductor

A coil of wire wrapped around an iron core. The inductance is directly proportional to the number of turns in the coil.

Polarity

A collective term applied to the positive (+) and negative ( - ) ends of a magnet or electrical mechanism such as a coil or battery.

Corona

A corona discharge is an electrical discharge brought on by the ionization of a fluid such as air surrounding a conductor that is electrically charged. Spontaneous corona discharges occur naturally in high-voltage systems unless care is taken to limit the electric field strength.

Ground Fault Circuit Interrupters

A device intended for the protection of personnel that functions to de-energize a circuit or portion thereof within an established period of time when a current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit.

Kilowatt-hour Meter

A device used to measure electrical energy use.

Resistor

A device usually made of wire or carbon which presents a resistance to current flow.

Generator

A device which converts mechanical energy into electrical energy.

Electromotive Force

A difference in potential that tends to give rise to an electric current. Measured in volts.

Waveform

A graphical representation ofelectrical cycles which shows the amount of variation in amplitude over some period of time.

Ferroresonance

(nonlinear resonance) a type of resonance in electric circuits which occurs when a circuit containing a nonlinear inductance is fed from a source that has series capacitance, and the circuit is subjected to a disturbance such as opening of a switch. It can cause overvoltages and overcurrents in an electrical power system and can pose a risk to transmission and distribution equipment and to operational personnel.

Ohm

(Ω) A unit of measure of resistance. One ohm is equivilant to the resistance in a circuit transmitting a current of one ampere when subjected to a potential difference of one volt.

B

A number 12 AWG copper wire is rated for how many amps? A. 15 amps B. 20 amps C. 10 amps D. 5 amps

A

A pictorial diagram is used to: a. Show component location. b. Indicate how the system works. c. Indicate part numbers of the devices. d. Determine wiring sizes for the equipment

Dielectric Constant

A quantity measuring the ability of a substance to store electrical energy in an electric field.

A

A rectified electrical current, as created by a rectifier, is one that: a. Changes alternating current into direct current b. Changes direct current into alternating current d. Destroys or wrecks the current e. Alternately pulsates DC and AC flow

Protective Relay

A relay device designed to trip a circuit breaker when a fault is detected.

B

A relay reduces or steps down voltage. a. TRUE b. FALSE

Variable Resistor

A resistor that can beadjusted to different ranges of value.

B

A schematic diagram is used to: a. Show component location. b. Indicate how the system works. c. Indicate the part numbers of the devices. d. Determine wire sizes for the appliance.

Transistor

A semiconductor device with three connections, capable of amplification in addition to rectification.

Diode

A semiconductor device with two terminals, typically allowing the flow of current in one direction only. Diodes allow current to flow when the anode is positive in relation to the cathode.

Semiconductor

A solid substance that has a conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects. Devices made of semiconductors, notably silicon, are essential components of most electronic circuits.

Electron

A tiny particle which rotates around the nucleus of an atom. It has a negative charge of electricity.

C

A transformer has a primary voltage of 120 volt and a secondary voltage of 4200 volt. The ratio for the transformer is: a. 4200:1 b. 42:1 c. 1:35 d. 1:4200

d

A transformer having a ratio of 1 : 85 with a primary voltage of 120 volt and 250 VA rating. What is the available secondary current side? a. 2.08 amps b. 0.48 amps c. 2.94 amps d. 0.0245 amps

B

A transformer that has 100 windings on the primary side and 20 windings on the secondary side has a ratio of: a. 1:5 b. 5:1 c. 1:1 d. 0.2

B

A transformer that has more windings on the primary side than on the secondary side would be considered a: a. Step up transformer b. Step down transformer c. Auto transformer d. Stationary transformer

A

A transformer that has more windings on the secondary side than on the primary side would be considered a: a. Step up transformer b. Step down transformer c. Auto transformer d. Stationary transformer

b

A transformer with a ratio of 1 : 85 would be considered a: a. Fixed transformer b. Step up transformer c. Variable core transformer d. Step down transformer

A

A transformer with a ratio of 10 : 1 has a primary voltage of 240 volts. With an available current of 6 amps on the secondary side. What is the VA rating of the transformer? a. 144 VA b. 1440 VA c. 24 VA d. 240VA

b

A transformer with a ratio of 5 : 1 has a primary voltage of 120 volts. What is voltage on the secondary side? a. 120 Volts b. 24 Volts c. 600 Volts d. 60 Volts

Volt

A unit measure of voltage. One volt is equal to the difference of potential that would drive one ampere of current against one ohm resistance.

Watt-hour

A unit of electrical energy equivalent to a power consumption of one watt for one hour.

Watt

A unit of electrical power. One watt is equivalent to one joule per second, corresponding to the power in an electric circuit in which the potential difference is one volt and the current one ampere.

Ampere-Hour

A unit of measure for battery capacity. It is obtained by multiplying the current (in amperes) by the time (in hours) during which current flows. For example, a battery which provides 5 amperes for 20 hours is said to deliver 100 ampere - hours.

Farad

A unit of measure for capacitance. One farad is equal to one coulomb per volt.

Hertz

A unit of measure for frequency. Replacing the earlier term of cycle per second (cps).

Henry

A unit of measure for inductance. If the rate of change of current in a circuit is one ampere per second and the resulting electromotive force is one volt, then the inductance of the circuit is one henry.

Ampere

A unit of measure for the intensity of an electric current flowing in a circuit. One ampere is equal to a current flow of one coulomb per second.

Volt-Ampere

A unit of measure of apparent power. It is the product of the rms voltage and the rms current.

VARS

A unit of measure of reactive power. Vars may be considered as either the imaginary part of apparent power, or the power flowing into a reactive load, where voltage and current are specified in volts and amperes.

Armoured Cable

AC (Designations)

B

All relay contacts on an electrical schematic must be designated: a. The same as the coil that operates them. b. The same as the amperage of the coil. c. With the device numbers they have. d. With the voltage applied to them.

Inverter

An apparatus that converts direct current into alternating current.

Circuit Breaker

An automatic device for stopping the flow of current in an electric circuit. To restore service, the circuit breaker must be reset (closed) after correcting the cause of the overload or failure. Circuit breakers are used in conjunction with protective relays to protect circuits from faults.

Direct Current

An electric current that flows in only one direction.

Alternating Current

An electric current that reverses its direction many times a second at regular intervals.

Relay

An electrical coil switch that uses a small current to control a much larger current.

Rectifier

An electrical device that converts an alternating current into a direct one by allowing a current to flow through it in one direction only.

D

An electrical multimeter includes which of the following meters? A. Voltmeter B. Ammeter C. Ohmmeter D. All the listed choices

Voltage

An electromotive force or "pressure" that causes electrons to flow and can be compared to water pressure which causes water to flow in a pipe. Measured in volts.

Ammeter

An instrument for measuring the flow of electrical current in amperes. Ammeters are always connected in series with the circuit to be tested.

Voltmeter

An instrument for measuring the force in volts of an electrical current. This is the difference of potential (voltage) between different points in an electrical circuit. Voltmeters have a high internal resistance are connected across (parallel to) the points where voltage is to be measured.

Ohmmeter

An instrument for measuring the resistance in ohms of an electrical circuit.

Open Circuit

An open or open circuit occurs when a circuit is broken, such as by a broken wire or open switch, interrupting the flow of current through the circuit. It is analogous to a closed valve in a water system.

Conductor

Any material where electric current can flow freely. Conductive materials, such as metals, have a relatively low resistance. Copper and aluminum wire are the most common conductors.

Insulator

Any material where electric current does not flow freely. Insulative materials, such as glass, rubber, air, and many plastics have a relatively high resistance. Insulators protect equipment and life from electric shock.

Electrolyte

Any substance which, in solution, is dissociated into ions and is thus made capable of conducting an electrical current. The sulfuric acid - water solution in a storage battery is an electrolyte.

Load

Anything which consumes electrical energy, such as lights, transformers, heaters and electric motors.

b

Are Three-way or Four-way switches considered as disconnecting means? a. Yes b. No

d

Calculate the Power of a simple circuit with an applied voltage of 120 volts, having a total current of 10 amps. Answer? a. 12 watts b. 0.83 watts c. 120 watts d. 1200 watts

b

Calculate the Power of a simple circuit with an applied voltage of 60 volts, having a total current of 10 amps. Answer? a. 10 watts b. 600 watts c. 120 watts d. 12 watts

2

Conventional Theory assumed electrons flowed from negative to positive 1. TRUE 2. FALSE

b

Current through the load of a parallel circuit increases as the resistance of the load increases a. TRUE b. FALSE

b

Current through the load of a parallel circuit increases as the resistance of the load increases a. TRUE b. FALSE

Dry Locations

D (Designations)

b

DC transformer will allow for a smoother transformer secondary output. a. TRUE b. FALSE

Piezoelectricity

Electric polarization in a substance (especially certain crystals) resulting from the application of mechanical stress (pressure).

C

Electrical current is measured in: A. Volts B. Ohms C. Amps D. Watts

a

Electrical power is: a. The rate that electrical energy is delivered to a load b. The resistance rating of a load c. The voltage rating of a load d. The amperage rating of a load

A

Electrical pressure is measured in: A. Volts B. Ohms C. Amps D. Watts

1

Electron theory states that electrons flow from negative to positive 1. TRUE 2. FALSE

Solid State Circuit

Electronic (integrated) circuits which utilize semiconductor devices such as transistors, diodes and silicon controlled rectifiers.

Kilowatt

Equal to 1000 watts.

a

Equipment that is being serviced or maintained must be made inoperative a. True b. False

12367

Five (5) items needed to complete a simple circuit are: (Check all correct answers, answer by example "13567") 1. Fuse 2. Switch 3. Conductors 4. Amps 5. Volts 6. Electrical Source 7. Load

D

For BX or AC wire, what needs to be inserted to protect the wire? A. Connector B. Wire end C. Wire connector D. Insulated bushing

b

Four zone valves rated at 8 VA each can operate safely attached to a transformer rated at 25 VA a. TRUE b. FALSE

a

Given a constant supply voltage, which statement is correct? a. The current through each branch circuit in a parallel circuit depends on the resistance of the load in that branch circuit b. The current through each branch circuit in a parallel circuit is not affected by the resistance of the load in that branch circuit c. The current through the main supply to all branch circuits in a parallel circuit will be less than the current passing through any of the individual branch circuits d. The current through each branch in a parallel circuit is reduced by the resistance of the loads in the other branches of the circuit

a

Given a constant supply voltage, which statement is correct? a. The current flow through each branch circuit in a series-parallel circuit depends on the resistance of the load(s) in that branch circuit. b. The current flow through each branch circuit in a series-parallel circuit is not affected by the resistance of the load(s) in that branch circuit. c. The current flow through the main supply to all branch circuits in a series-parallel circuit will always be less than the current passing through any of the individual branch circuits. d. The current flow through each load in a series-parallel circuit will be reduced by the resistance of the other loads in the complete circuit.

a

Given a constant supply voltage, which statement is correct? a. The current through each branch circuit in a parallel circuit depends on the resistance of the load in that branch circuit b. The current through each branch circuit in a parallel circuit is not affected by the resistance of the load in that branch circuit c. The current through the main supply to all branch circuits in a parallel circuit will be less than the current passing through any of the individual branch circuits d. The current through each branch in a parallel circuit is reduced by the resistance of the loads in the other branches of the circuit

Green/Bare Wires

Ground

Black/Red/Blue Wires

Hot Wires

2

Hot wires allow electrons to flow easier than cold wires 1. TRUE 2. FALSE

d

How long is a lock-out device allowed to be on a piece of equipment? a. One hour b. One day c. One week d. As long as it takes to finish working on the equipment

b

How many amps does it take to kill a person? a. 10 milliamps can kill a person b. Less than one amp can kill a person c. Amps do not kill � its the voltage that kills d. Amps do not kill � its the resistance that kills

1

How many electrons are on the valance shell of a copper atom? 1. One 2. Two 3. Three 4. Four

a

How many lock-out devices are allowed on a piece of equipment? a. The same number as there is workers working on the equipment b. Just one c. Maximum 6 d. There is no need to place a lock-out device on at anytime

c

If 200 volts are applied to a complete and activated simple circuit with a 20 Ohm load. How many volts are there across the load? a. 10 Amps b. 2000 Watts c. 200 Volts d. 20 Ohms

a

If 200 volts are applied to a complete simple circuit with a 20 Ohm load. If the switch is open (OFF) what is the voltage across the load? a. Zero Volts b. 120 Volts c. 10 Amps d. 2000 Watts

d

If a 10 ohm resistive load has 2 amps of current passing through the load what is the power consumed by the load? a. 20 Watts b. 20 Volts c. 40 Volts d. 40 Watts

d

If a 10 ohm resistive load has 2 amps of current passing through the load what is the power consumed by the load? a. 20 Watts b. 20 Volts c. 40 Volts d. 40 Watts

b

If a load is designed for 120V, which type of circuit will allow it to deliver its design power rating? a. Series circuit b. Parallel circuit - no matter which branch it is installed in c. Series-parallel circuit - no matter which branch it is installed in d. All of the listed choices

c

If a person can not let go of a live wire, which of the following is the best option to save the person a. Separate the live wire and the person using a pole b. Apply CPR or artificial respiration c. Disconnect the electricity to that circuit d. Document the incident for the inspector

C

If a relay coil designated R 3is energized,it will cause all : a. R1-3contacts to change position. b. R1-3contacts to open. c. R3 contacts to change position. d. R3 contacts to open.

C

If a solenoid rated at 24 volts has a reading of 24 volts across the terminals but the solenoid is not working properly, what could be a possible problem from the list choices? a. The fuse is blown in the circuit b. The main switch is open c. The coil has a broken wire d. All of the listed choices

A

If a solenoid rated at 24 volts has a reading of zero volts across the terminals but the solenoid is not working properly, what could be a possible problem from the list choices? a. The fuse is blown in the circuit b. The main switch is closed c. The coil has a broken wire d. All of the listed choices

D

If a voltage drop is measured across the contacts of a relay switch, the most probable cause is: a. The relay contacts are dirty or corroded b. The coil is shorted to the casing of the device and not energized c. The coil wire is broken d. All of the listed choices

b

If one or more of the loads wired in parallel in a series-parallel circuit is not operating, none the other loads in the circuit will operate. a. TRUE b. FALSE

d

If resistance is increased (i.e. not added) in one or more branch circuit(s): a. Voltage increases b. Total current increases c. Voltage decreases d. Total current decreases

c

If the current in a circuit is 5 amps and the power consumed is 100 watts, the voltage drop across the resistive load is: a. 1 volt b. 10 volts c. 20 volts d. 120 volts

c

If the current in a circuit is 5 amps and the power consumed is 100 watts, the voltage drop across the resistive load is: a. 1 volt b. 10 volts c. 20 volts d. 120 volts

c

If the main switch of a series-parallel circuit is in the closed position (On), what would be the voltage reading across the switch? a. Applied Current b. Applied Voltage c. Zero Volts d. Zero Ohms

b

If the main switch of a series-parallel circuit is in the open position (Off), what would be the voltage reading across the switch? a. Applied Current b. Applied Voltage c. Zero Volts d. Zero Ohms

d

If the supply voltage to a parallel circuit is 120 volts, and there are three (3) resistive loads of 120 ? each, the total current is: a. 0 amps b. 1 amps c. 2 amps d. 3 amps

d

If the supply voltage to a parallel circuit is 120 volts, and there are three (3) resistive loads of 120 ? each, the total current is: a. 0 amps b. 1 amps c. 2 amps d. 3 amps

b

If the supply voltage to a parallel circuit is 120 volts, and there are three (3) resistive loads of 120 Ω each, the current through each branch circuit is: a. 0 amps b. 1 amps c. 2 amps d. 3 amps

b

If the supply voltage to a parallel circuit is 120 volts, and there are three (3) resistive loads of 120 Ω each, the current through each branch circuit is: 0 amps 1 amps 2 amps 3 amps

c

If the supply voltage to a parallel circuit is 60 volts, and there are three (3) resistive loads of 120 ? each, the current through each branch circuit is: a. 0.5 amps b. 1.5 amps c. 2.5 amps d. 3.5 amps

a

If the supply voltage to a parallel circuit is 60 volts, and there are three (3) resistive loads of 120 ? each, the current through each branch circuit is: a. 0.5 amps b. 1.5 amps c. 2.5 amps d. 3.5 amps

b

If the supply voltage to a parallel circuit is 60 volts, and there are three (3) resistive loads of 120 ? each, the total current is: a. 0.5 amps b. 1.5 amps c. 2.5 amps d. 3.5 amps

b

If the supply voltage to a parallel circuit is 60 volts, and there are three (3) resistive loads of 120 ? each, the total current is: a. 0.5 amps b. 1.5 amps c. 2.5 amps d. 3.5 amps

c

If the voltage drop across a load is 90 volts and the current in the circuit is 3 amps, the resistance presented by the load must be: a. 0 Ω b. 3 Ω c. 30 Ω d. Depends on the resistance of the other loads in the circuit

b

If the voltage drop across a resistive load is 50 volts and the power consumed is 100 watts, the current is: a. 0 amps b. 2 amps c. 0.5 amps d. Different on either side of the load

b

If the voltage drop across a resistive load is 50 volts, and the power consumed is 100 watts, the current is: a. 0 amps b. 2 amps c. 0.5 amps d. Different on each side of the load

b

If the voltage drop across a resistive load is 50 volts, and the power consumed is 100 watts, the current is: a. 0 amps b. 2 amps c. 0.5 amps d. Different on each side of the load

b

If the voltage drop across the load is 120 volts, and the current through the load is 3 amps, the power consumed by the load is: a. 120 watts b. 360 watts c. 40 amps d. 40 watts

b

If the voltage drop across the load is 120 volts, and the current through the load is 3 amps, the power consumed by the load is: a. 120 watts b. 360 watts c. 40 amps d. 40 watts

c

If the voltage supply to a series circuit is 120 volts and there are three (3) loads of 10 Ω each, the current reading will be: a. 0 amps b. 2 amps c. 4 amps d. Depends on the fuse in the circuit

b

If two equal resistive loads are wired in series to a series-parallel circuit with an applied voltage of 120V, the voltage drop across each of the series loads will be: a. 120V b. 60V c. 40V for the first load and 80V for the second load d. 120V for the first load and 60V for the second load

b

If voltage applied to the following circuit is 120 volts, and the resistance of all the loads are 120 ohms. A reading of 120 volts is taken across R3. This reading would indicate: a. Series Branch is Operational b. R3 is Defective c. Series Branch is Flickering d. R4 is Defective

d

If voltage applied to the following circuit is 120 volts, and the resistance of all the loads are 120 ohms. A reading of 120 volts is taken across R4. This reading would indicate: a. Series Branch is Operational b. R3 is Defective c. Series Branch is Flickering d. R4 is Defective

a

If voltage applied to the following circuit is 120 volts, and the resistance of all the loads are 120 ohms. A reading of 60 volts is taken across R4. This reading would indicate: a. Series Branch is Operational b. R3 is Defective c. Series Branch is Flickering d. R4 is Defective

c

If voltage applied to the following circuit is 120 volts, and the resistance of all the loads are 120 ohms. What is the total current of the circuit? a. 3 amps b. 1 amps c. 2.5 amps d. 2 amps

d

In a complete and activated simple circuit how many amps are flowing through a 15 ohm load with 300 volts applied? a. 4500 amps b. 0.05 amps c. 45 amps d. 20 amps

b

In a complete and activated simple circuit the resistance of the load is 6 ohms with a voltage applied to the load of 120 volts. How many amps are flowing through the load? a. 720 amps b. 20 amps c. 0.05 amps d. 126 amps

b

In a complete and activated simple circuit with 100 volts applied to load of 200 ohms. What is the total current of the circuit? a. 200 amps b. 0.5 amps c. 2 amps d. 2,000 amps

a

In a complete and activated simple circuit with 200 volts applied to load of 20 ohms. What is the total current of the circuit? a. 10 amps b. 0.5 amps c. 20 amps d. 4,000 amps

d

In a complete and activated simple circuit with 200 volts applied to the circuit and having 50 amps through the load. What is the total resistance? a. 1000 Ohms b. 250 Ohms c. 0.25 Ohms d. 4 Ohms

a

In a complete and activated simple circuit with a load of 100 ohms and the total current of 0.5 amps. What is the voltage across the load? a. 50 Volts b. 200 Volts c. 0.05 Volts d. 100 Volts

b

In a complete and activated simple circuit with a load of 100 ohms and the total current of 2 amps. What is the voltage across the load? a. 50 amps b. 200 amps c. 0.2 amps d. 102 amps

d

In a complete and live series circuit, the amperage reading will be: a. The same in all parts of the circuit b. Supply amperage c. Depends on the resistance of the loads in the circuit d. Both "a" and "c"

a

In a parallel circuit, as voltage increases, current: a. Increases b. Decreases c. Stays the same d. Fluctuates

A

In a parallel circuit, as voltage increases, current: a. Increases b. Decreases c. Stays the same d. Fluctuates

d

In a parallel circuit, if the resistance is increased (ie. Not Added) in one or more branch circuit(s): a. Voltage increases b. Total current increases c. Voltage deceases d. Total current decreases

d

In a parallel circuit, if the resistance is increased (ie. Not Added) in one or more branch circuit(s): a. Voltage increases b. Total current increases c. Voltage deceases d. Total current decreases

d

In a parallel circuit, the amperage reading at any point in the circuit will be: a. 0 Amps b. Supply amperage c. The same d. Different on the main line compared to each branch line

d

In a parallel circuit, the amperage reading at any point in the circuit will be: a. 0 Amps b. Supply amperage c. The same d. Different on the main line compared to each branch line

b

In a parallel circuit, with three (3) branches each having the same resistive load, how many watts will be across each load if the total power of the circuit is 900 watts? a. 900 Watts b. 300 Watts c. 2700 Watts d. 100 Watts

b

In a parallel circuit, with three (3) branches each having the same resistive load, how many watts will be across each load if the total power of the circuit is 900 watts? a. 900 Watts b. 300 Watts c. 2700 Watts d. 100 Watts

b

In a series circuit. The amperage reading at any point in the circuit will be: a. 0 amps b. The same c. Supply amperage d. Different on either side of the load

d

In a series-parallel circuit, the amperage readings in the circuit will be: a. The same b. Different on main line compared to each branch line c. The same in all parts of the series branch circuit d. Both b) and c)

True

In an operational series circuit, voltage drop across a load increases as resistance of the load is increased. (T/F)

A

Invertors convert DC to AC a. TRUE b. FALSE

Low Voltage

LV (Designations)

1

Larger diameter wires have less resistance to flow than thin wires 1. TRUE 2. FALSE

2

Length has no importance to the resistance of a wire 1. TRUE 2. FALSE

True Power

Measured in Watts. The power manifested in tangible form such as electromagnetic radiation, acoustic waves, or mechanical phenomena. In a direct current (DC) circuit, or in an alternating current (AC) circuit whose impedance is a pure resistance, the voltage and current are in phase.

Apparent Power

Measured in volt-ampers (VA). Apparent power is the product of the rms voltage and the rms current.

False

Most circuits in a residential house are series circuits (T/F)

B

Motor need what type of fuse: A. GP B. D C. NM D. L

Non-Metallic

NM (Designations)

White/Natural Gray/Ribbed Wires

Neutral

Oil Resistant

O (Designations)

Mutual Induction

Occurs when changing current in one coil induces voltage in a second coil.

D

On a schematic diagram, the safety controls are typically drawn: a. To the right of the loads. b. Above the loads. c. Below the loads. d. To the left of the loads.

B

On an electrical schematic, all operating controls are drawn: a. In their energized positions. b. In their de-energized positions. c. Normally closed. d. Normally open

D

On an electrical schematic, the system is shown with the: a. Disconnect closed and with all devices as though the heating is on. b. Disconnect closed and with all devices as though there is a call for action but the operation has not yet come activated. c. Disconnect open and with all devices as though there is a call for action. d. Disconnect open and with all devices as though there is no call for action.

a

Only Alternating Current will allow the secondary windings of a transformer to be induced with a pulsating magnetic field a. TRUE b. FALSE

1

Opposite charges attract one another 1. TRUE 2. FALSE

1

Oxygen is a good conductor 1. TRUE 2. FALSE

2

Oxygen is a good conductor 1. TRUE 2. FALSE

A

Relays are normally powered by low-voltage circuits of less than 10 amps while contactors are rated for currents of more than 10 amps. a. True b. False

B

Resistance is measured in: A. Volts B. Ohms C. Amps D. Watts

Service Cable

S (Designations)

A

Stationary Iron core transformers are considered near 100% efficiency a. TRUE b. FALSE

Thermoplastic

T (Designations)

Volts

The Letter "E" Represents:

Amps

The Letter "I" Represents:

Watts

The Letter "P" Represents:

Ohms

The Letter "R" Represents:

B

The VA rating of a transformer will inform the technician of the available current on the: a. Primary side b. Secondary side c. Supply current d. Supply voltage

Capacitance

The ability of a body to store an electrical charge. Measured in farads as the ratio of the electric charge of the object (Q, measured in coulombs) to the voltage across the object (V, measured in volts).

Demand

The average value of power or related quantity over a specified period of time.

Cycle

The change in an alternating electrical sine wave from zero to a positive peak to zero to a negative peak and back to zero. See Frequency.

A

The colour wire that is used for ground is: A. Green B. White C. Black D. Red

B

The colour wire that is used for neutral is: A. Green B. White C. Black D. Red

Load Rejection

The condition in which there is a sudden load loss in the system which causes the generating equipment to be over-frequency. A load rejection test confirms that the system can withstand a sudden loss of load and return to normal operating conditions using its governor. Load banks are normally used for these tests as part of the commissioning process for electrical power systems.

Service

The conductors and equipment used to deliver energy from the electrical supply system to the system being served.

d

The factors affecting power consumption of any one load in a series circuit are: a. Voltage drop across the load b. Amount of current flow in the circuit c. The resistance of the other loads in the circuit d. All the listed choices

Current

The flow of an electric charge through a conductor. An electric current can be compared to the flow of water in a pipe. Measured in amperes.

True

The higher the current flow through a load, the higher the power produced by the load. For example, a 100 watt light bulb with a current of 0.8 amps will glow brighter than the same bulb with a current of 0.4 amps. (T/F)

True

The higher the power rating of a load, the lower the resistance to flow through that load. For example, a light bulb with a power rating of 100 watts will allow more current than a bulb with a rating of 40 watts. (T/F)

a

The main disconnect switch is wired in series with the loads in a parallel circuit a. TRUE b. FALSE

a

The main disconnect switch is wired in series with the loads in a parallel circuit a. TRUE b. FALSE

b

The main fuse is wired in parallel to all loads in a series-parallel circuit. a. TRUE b. FALSE

b

The main fuse is wired in parallel with the loads in a parallel circuit a. TRUE b. FALSE

b

The main fuse is wired in parallel with the loads in a parallel circuit a. TRUE b. FALSE

Ohm's Law

The mathematical equation that explains the relationship between current, voltage, and resistance (V=IR).

Ampacity

The maximum amount of electric current a conductor or device can carry before sustaining immediate or progressive deterioration.

Dielectric Strength

The maximum electric field that a pure material can withstand under ideal conditions without breaking down (i.e., without experiencing failure of its insulating properties).

Inpedance

The measure of the opposition that a circuit presents to a current when a voltage is applied. Impedance extends the concept of resistance to AC circuits, and possesses both magnitude and phase, unlike resistance, which has only magnitude.

D

The meter used to check for continuity is called a(n): A. Continuity Tester B. Ammeter C. Ohmmeter D. Both a) and c)

B

The meter used to measure electrical current is called a(n): A. Voltmeter B. Ammeter C. Ohmmeter D. Potentiometer

A

The meter used to measure electrical potential is called a(n): A. Voltmeter B. Ammeter C. Ohmmeter D. Potentiometer

C

The meter used to measure electrical resistance is called a(n): A. Voltmeter B. Ammeter C. Ohmmeter D. Potentiometer

Armature

The movable part of a generator or motor. It is made up of conductors which rotate through a magnetic field to provide voltage or force by electromagnetic induction. The pivoted points in generator regulators are also called armatures.

Frequency

The number of cycles per second. Measured in Hertz. If a current completes one cycle per second, then the frequency is 1 Hz; 60 cycles per second equals 60 Hz

Resistance

The opposition to the passage of an electric current. Electrical resistance can be compared to the friction experienced by water when flowing through a pipe. Measured in ohms.

Reactive Power

The portion of electricity that establishes and sustains the electric and magnetic fields of AC equipment. Exists in an AC circuit when the current and voltage are not in phase. Measured in VARS.

Kilowatt-hour

The product of power in kW and time in hours. Equal to 1000 Watt-hours. For example, if a 100W light bulb is used for 4 hours, 0.4kWhs of energy will be used (100W x 1kW / 1000 Watts x 4 hours). Electrical energy is sold in units of kWh.

Inductance

The property of a conductor by which a change in current flowing through it induces (creates) a voltage (electromotive force) in both the conductor itself (self-inductance) and in any nearby conductors (mutual inductance). Measured in henry (H).

Power

The rate at which electrical energy is transferred by an electric circuit. Measured in Watts.

Power Factor

The ratio of the actual electrical power dissipated by an AC circuit to the product of the r.m.s. values of current and voltage. The difference between the two is caused by reactance in the circuit and represents power that does no useful work.

Ground

The reference point in an electrical circuit from which voltages are measured, a common return path for electric current, or a direct physical connection to the Earth.

True

The resistance of a load determines the voltage drop across the load in a operational series circuit (T/F)

Reluctance

The resistance that a magnetic circuit offers to lines of force in a magnetic field.

Rotor

The rotating part of an electrical machine such as a generator, motor, or alternator.

A

The secondary side of the transformer should be grounded by bonding: a. The common wire to ground b. The hot wire to ground c. The core to neutral d. The primary to secondary

b

The sum of the voltage drops across each load in a parallel circuit equals the supply voltage a. TRUE b. FALSE

b

The sum of the voltage drops across each load in a parallel circuit equals the supply voltage a. TRUE b. FALSE

True

The sum of the voltage drops in a series circuit equals the supply voltage (T/F)

Electron Theory

The theory which explains the nature of electricity and the exchange of "free" electrons between atoms of a conductor. It is also used as one theory to explain direction of current flow in a circuit.

d

The total current in a parallel circuit (ie. Taken at the source) will be: a. 0 volts b. Supply amperage c. 0 amps d. The sum of the current running through each branch circuits

d

The total current in a parallel circuit (ie. Taken at the source) will be: a. 0 volts b. Supply amperage c. 0 amps d. The sum of the current running through each branch circuits

d

The total current in a series-parallel circuit (i.e. taken at source) will be: a. 0 Volts b. Supply amperage c. 0 Amps d. The sum of the current passing through each branch circuit

d

The total resistance of a parallel circuit that consist of three(3) branch circuits each with thirty(30) ohm resistive loads is: a. 90 Ω b. 15 Ω c. 30 Ω d. 10 Ω

d

The total resistance of a parallel circuit that consist of three(3) branch circuits each with thirty(30) ohm resistive loads is: a. 90 Ω b. 15 Ω c. 30 Ω d. 10 Ω

a

The total resistance of a parallel circuit that consist of two(2) branch circuits each with Five(5) ohm resistive loads is: a. 2.5 Ω b. 5 Ω c. 10 Ω d. Depends on the supply voltage to the circuit

a

The total resistance of a parallel circuit that consist of two(2) branch circuits each with Five(5) ohm resistive loads is: a. 2.5 Ω b. 5 Ω c. 10 Ω d. Depends on the supply voltage to the circuit

c

The total resistance of a series circuit that consists of two 5 Ω loads is: a. 2.5 Ω b. 5 Ω c. 10 Ω d. Depends on the supply voltage to the circuit

b

The voltage applied to the parallel branch of the circuit will equal the sum of the voltage drops of each load in the circuit. a. TRUE b. FALSE

a

The voltage applied to the series branch of the circuit will equal the sum of the individual voltage drops of each individual load in that series branch. a. TRUE b. FALSE

d

The voltage drop across an open main switch, in a parallel circuit will be: a. 0 Volts b. 0 Amps c. Supply Amperage d. Supply voltage

d

The voltage drop across an open main switch, in a parallel circuit will be: a. 0 Volts b. 0 Amps c. Supply Amperage d. Supply voltage

a

The voltage drop across each branch circuit in a series-parallel circuit equals the supply voltage. a. TRUE b. FALSE

D

The voltage drop from each terminal of an open switch to ground will be: a. 0 volts b. Supply voltage c. Depends on the resistance of the loads in the circuit d. Supply voltage from one terminal and 0 volts from the other terminal

b

The voltage reading across a load in a series circuit will be: a. 0 volts b. Supply voltage c. Depends on the resistance of the load in the circuit d. 0 amps

Wattmeter

The wattmeter is an instrument for measuring the electric power (or the supply rate of electrical energy) in watts of any given circuit.

B

The wire designation "AC" represents: A. Alternating Current B. Armoured Cable C. Assisted Circuit D. Aroma Circuit

B

The wire designation "NM" represents: A. Not Much B. Non Metalic C. Negative Movement D. Next Method

B

The wire designation "S" represents: A. Secondary B. Service C. System D. Supply

c

Total resistance (Rt) in a series circuit is equal to: a. Supply amperage b. Supply voltage c. Sum of each individual resistance in the circuit d. 0 Ω

c

Turning off a load in a branch circuit of a series-parallel circuit has what effect on total current? a. None b. Amperage increases c. Amperage decreases d. Amperage fluctuates

Underground

U (Designations)

True

Voltage applied to the circuit is voltage consumed by the circuit (T/F)

2

Voltage is applied to ____________ electrons 1. Flow 2. Push 3. Attract 4. Freeze

Self Induction

Voltage which occurs in a coil when there is a change of current.

Wet Locations

W (Designations)

a

What are the total amps when 120 volts are applied to a 100 watt load? a. 0.83 amps b. 12000 amps c. 1.2 amps d. 100 amps

c

What are the total amps when 120 volts are applied to a 100 watt load? a. 0.83 amps b. 12000 amps c. 1.2 amps d. 100 amps

d

What are the total amps when 120 volts are applies to a 60 watt load? a. 7200 amps b. 2 amps c. 180 Amps d. 0.5 amps

c

What are the total watts when 100 volts are applied to a 2 ohm load? a. 200 Watts b. 50 watts c. 5000 watts d. 100 watts

Ampere

What does A represent when it comes to electrical theory?

Alternating Current

What does AC represent when it comes to electrical theory?

Ampere-Hour

What does Ah represent when it comes to electrical theory?

Direct Current

What does DC represent when it comes to electrical theory?

Ground Fault Circuit Interrupters

What does GFCI represent when it comes to electrical theory?

Volt

What does V represent when it comes to electrical theory?

Volt-Ampere

What does VA represent when it comes to electrical theory?

Watt

What does W represent when it comes to electrical theory?

Watt-hour

What does Wh represent when it comes to electrical theory?

Kilowatt

What does kW represent when it comes to electrical theory?

Kilowatt-hour

What does kWh represent when it comes to electrical theory?

Bimetal Overload

What does this symbol represent?

Cartridge Type Fuse

What does this symbol represent?

Circuit Breaker Closed

What does this symbol represent?

Circuit Breaker Open

What does this symbol represent?

Fuse

What does this symbol represent?

Thermal Overload with Heater

What does this symbol represent?

D

What is the maximum number of 14 AWG wire are allowed under one #33 Wire connector A. 1 B. 2 C. 3 D. 4

D

What is the voltage reading across the pump in the following diagram: a. Zero volts b. 120 volts c. Zero ohms d. 24 volts

a

What is the Ω symbol on a CSA approved work boot mean? a. Dielectric resistance b. Good luck c. Ferrier approved d. All of the above

d

What size of a transformer would be needed to safely operate a circuit consisting of five (5) zone valves rated at 6 VA a. 6VA b. 10 VA c. 25 VA d. 50 VA

B

When a plug fused is removed from the circuit and is found to be black inside, this is an indication of: A. A fuse that indicates the limit of the rating has been exceeded B. A fuse that indicates it has had a short circuit occur C. A fuse that is still good D. A fuse that needs to be recharged

Short Circuit

When one part of an electric circuit comes in contact with another part of the same circuit, diverting the flow of current from its desired path.

d

Which conductor is considered the better conductor? a. Silver b. Copper c. Aluminum d. Gold

A

Which direction should wires be twisted together before installing a wire connector? A. Clockwise B. Counter clockwise

d

Which of the following are the factors effecting electrical shock? a. Amount of current flowing through the body b. Amount and type of voltage c. Resistance of the human body d. All of the above

a

Which of the following calculations will determine the electrical power consumed by a resistive load? a. Voltage times current b. Resistance time current c. Voltage divided by resistance d. Voltage divided by current

b

Which of the following is NOT considered an insulator a. Glass b. Water c. Wood d. Rubber

a

Which of the following light bulbs will consume the most electrical power? a. 200 watt b. 100 watt c. 60 watt d. 40 watt

d

Which of the following windings will create a stronger magnetic field in a relay coil? a. A coil with 100 wire turns and a current of 100 mA b. A coil with 10 wire turns and a current of 100 mA c. A coil with 100 wire turns and a current of 10 mA d. A coil with 1000 wire turns and a current of 1 A

b

Which statement is correct concerning a parallel circuit? a. The total resistance of the circuit is the sum of the individual resistance in the circuit b. The total resistance of the circuit will be less than the smallest resistance in the circuit c. The current reading will be the same no matter where it is taken in the circuit d. Voltage drop across each load is less than the supply voltage

b

Which statement is correct concerning a parallel circuit? a. The total resistance of the circuit is the sum of the individual resistance in the circuit b. The total resistance of the circuit will be less than the smallest resistance in the circuit c. The current reading will be the same no matter where it is taken in the circuit d. Voltage drop across each load is less than the supply voltage

d

Which statement is correct? a. As resistance increases in a series circuit, voltage increases b. As resistance increases in a series circuit, amperage increases c. As resistance increases in a series circuit, voltage decreases d. As resistance increases in a series circuit, amperage decreases

a

Which statement is correct? a. As resistance increases in a series circuit. Power usage decreases b. As voltage increases in a series circuit. Power usage decreases c. As current increases in a series circuit. Power usage decreases d. As resistance increases in a series circuit. Power usage increases

c

Which statement is correct? a. Current will still flow with one load not functioning in a series circuit b. Varying the voltage or resistance in a series circuit does not effect current c. Current will be the same throughout the series circuit d. Current will be different after each load in a series circuit

B

Which statement is correct? a. The series-parallel circuit is the most common type of circuit used in residential appliances b. A corroded switch will cause a parallel circuit to act like a series-parallel c. The series circuit is the only type of circuit used in oil appliances d. The parallel circuit is never used in appliances

c

With 120 volts applied to a 10 Ohm load in a simple circuit .What is the voltage across a closed (ON) switch? a. 120 Volts b. 12 Amps c. 0 Volts d. 10 Ohms

a

With 120 volts applied to a 10 Ohm load in a simple circuit. What is the voltage across an open (OFF) switch? a. 120 Volts b. 12 Amps c. 0 Volts d. 10 Ohms

b

With a constant supply voltage, As the resistance increases in one or more of the branches of a parallel circuit, the power consumption: a. Increases b. Decreases c. Stays the same d. Reduces the voltage drop across that branch

b

With a constant supply voltage, As the resistance increases in one or more of the branches of a parallel circuit, the power consumption: a. Increases b. Decreases c. Stays the same d. Reduces the voltage drop across that branch

b

With a constant supply voltage, decreasing the resistance of loads in a series circuit has what affect on the current? a. None b. Amperage increases c. Amperage decreases d. Amperage fluctuates

b

With a constant supply voltage, increasing the number of branch circuits with a load in a parallel circuit, has what effect on the total current draw? a. None b. Amperage increases c. Amperage decreases d. Amperage fluctuates

b

With a constant supply voltage, increasing the number of branch circuits with a load in a parallel circuit, has what effect on the total current draw? a. None b. Amperage increases c. Amperage decreases d. Amperage fluctuates

c

With a constant supply voltage, increasing the number of loads in a series circuit has what affect on the current? a. None b. Amperage increases c. Amperage decreases d. Amperage fluctuates

c

With a constant supply voltage, shutting off a load in any one branch circuit of a parallel circuit, has what effect on the total current draw? a. None b. Amperage increases c. Amperage decreases d. Amperage fluctuates

c

With a constant supply voltage, shutting off a load in any one branch circuit of a parallel circuit, has what effect on the total current draw? a. None b. Amperage increases c. Amperage decreases d. Amperage fluctuates

b

With constant supply voltage, increasing the number of parallel branch circuits with a load has what effect on total current draw? a. None b. Amperage increases c. Amperage decreases d. Amperage fluctuates


Kaugnay na mga set ng pag-aaral

ATI: Chapter 31 Angina and Myocardial Infarction

View Set

18.3 Directors and officers and shareholders

View Set

Series 7: Chapter 18. Investment Companies and other Packaged Products.

View Set

Introduction to Public Health Exam 2

View Set

PMK-EE E5 Leadership & Character

View Set

John of Damascus, Doctor of the Church

View Set

[Lección 4] Estructura 3.1 - En el cine

View Set