Previous Exam Answers
Dry-type transformers rated over which voltage shall be installed in a vault?
35,000 volts
For other than a totally enclosed switchboard or switchgear, what is the minimum amount of space that shall be provided between the top of an unshielded switchboard or switchgear and any combustible ceiling?
36 inches Find Citation.
Approximately how many kilowatts are used by a three-phase, 480-volt ac motor that draws a current of 52 amperes and has a power factor rating of 88%?
38 kW Watts = 3phase x 480-volt x 52amp?????
Disregarding exceptions, liquidtight flexible metal conduit shall be supported and secured at intervals not to exceed
4 1/2 feet
How many quarter bends are allowed in IMT between pull points?
4 bends
All employees must receive training on working in confined and enclosed spaces when working in open pits that are greater than how many feet in depth?
4 feet
A motor with a code letter of D shall have what range of kilowatt-amperes per horsepower with locked rotor?
4.00 to 4.49
An appliance for a residence is rated at 30 amperes. It is continuously loaded and is not motor-operated. What is the minimum branch circuit rating that is required if the branch circuit device is not listed for continuous loading?
40 Amperes
What is the minimum branch-circuit rating for ranges of 8-3/4 kW or more?
40 amperes
Infrared lamp commercial and industrial heating appliances shall have overcurrent protection NOT exceeding which of the following?
50 Amperes
The feeder conductor ampacity shall not be less than that of the service conductors where the feeder conductors carry the total load supplied by service conductors with an ampacity of:
55 Amperes or less Find citation
Disregarding exceptions, what is the minimum size copper-clad aluminum underground service conductor permitted?
6 AWG
The nameplate on a nonmotor generator arc welder shows the primary current is 60 amperes with a duty rating of 80%. What is the minimum allowable AWG size copper conductor with TW insulation?
6 AWG
What is the minimum size copper conductor permitted for use for a 6,000 volt service?
6 AWG
What is the minimum size copper equipment grounding wire for a 150 amp feeder?
6 AWG
What is the minimum size copper-clad aluminum equipment grounding conductor for a feeder with a 100-ampere overcurrent protection device?
6 AWG
What is the maximum number of disconnects permitted per service grouped in any one location?
6 disconnects
A GFCI-type receptacle is required if installed within how many feet from the outside edge of the sink?
6 feet
If installed and routed on the outside of a raceway, the length of the equipment bonding jumper shall not exceed how many feet?
6 feet
What is the maximum spacing for supports of 10 AWG copper conductors located in a vertical raceway?
100 feet
What is the ampere load of a 3-hp single-phase motor at 240 volts with an efficiency rating of 83%?
11.23 Amperes
The base of a 24-foot non-self-supporting ladder shall be placed approximately how far from the vertical structure upon which is leaning?
6 feet
Unless otherwise provided, MC cables shall be secured at intervals not exceeding which of the following?
6 feet
Where practicable, what is the minimum amount of separation that shall be maintained between communications wires and cables on buildings and lightning conductors?
6 feet
Receptacles in residential units shall be installed such that no point measured horizontally along the floor line of any wall space is more than how far from a receptacle outlet?
6 feet Find citation
What is the maximum weight of a luminaire that can be supported by the screw shell of a lampholder?
6 pounds
Resistance-type heating elements in electric space-heating equipment shall be protected at not more than how many amperes?
60 amperes
The ampacity of the conductors from the generator terminals to the first distribution device(s) containing overcurrent protection shall not be less than what percentage of the nameplate current rating?
115%
What clearance must be maintained when overhead spans of open conductors or open multiconductor cables of not over 1,000 volts, nominal, pass over residential property?
12 feet
Conductors that supply a single motor used in a continuous duty application shall have an ampacity of not less than what percentage of the motor full-load current rating?
125%
Overcurrent protection for feeders and branch circuits supplying electric vehicle supply equipment shall be sized for continuous duty and shall have a rating of not less than what percentage of the maximum load of the electric vehicle supply equipment?
125%
Where a feeder supplies continuous loads or any combination of continuous and noncontinuous loads, the minimum feeder conductor size shall have an allowable ampacity not less than the noncontinuous load plus what percentage of the continuous load?
125%
What is the minimum size grounding equipment conductor required for a photovoltaic system?
14 AWG
Receptacles used for circuits and equipment operating at less than 50 volts shall have a minimum rating of how many amperes?
15 Amperes
Information technology equipment shall be permitted to be connected to a branch circuit by a power-supply cord with a maximum length of how many feet?
15 feet
Plug fuses shall be permitted to be used in circuits supplied by a system having a grounded neutral point where the line-to-neutral voltage does NOT exceed which of the following?
150 volts
Alternating-current systems of less than 50 volts shall be grounded where supplied by transformers, if the transformer supply system exceeds which of the following?
150 volts to ground
Two 12 AWG stranded uncoated copper conductors are run 100 feet; the current through the circuit is 20 amperes. What is the power loss of the conductors?
158 watts
Where the rated input current of the autotransformer is less than 9 amperes, what is the maximum permitted overcurrent device rating?
167% of the input current
In a power-limited fire alarm circuit, transformers supplied from power-supply conductors shall be protected by an overcurrent device rated not over
20 Amperes
Snap switches directly connected to aluminum conductors shall be listed and marked CO/ALR if rated at
20 Amperes or less
A resistor has the following colored bands (in order): orange, red, brown, silver. What is the resistor value?
320 Ohms (10% tolerance) Resistor Band Chart:
Which is NOT considered a hermetic seal?
Compression Gasket
Who is responsible for providing head protective gear to employees who are working in areas where there is a possible danger of head injury from impact, falling or flying objects, or from electrical shock and burns?
Employer
Unlisted nonconductive outside plant optical fiber cables shall not be permitted to be installed in which type of raceways?
Flexible Metal Conduit
Which is best defined as an unintentional, electrically conductive connection between an ungrounded conductor of an electrical circuit and the normally non-current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or earth?
Ground fault
What must circuit breakers used as switches in high-intensity discharge lighting circuits be marked as?
HID (High Intensity Discharge Lighting)
Where is AC cable NOT permitted to be used?
In damp locations
Where are flat cable assemblies permitted to be installed?
In exposed locations
Which type of electrical equipment is used to change voltage level or waveform, or both, of electrical energy?
Inverter
What is the maximum number of 12 AWG conductors that can be used in a 4" x 1-1/2" square box?
Nine (Box fill)
Lamp tie wires, mounting screws, clips, and decorative bands on glass shall not be required to be grounded if spaced at least how far from the lamp terminals?
1 1/2 inches
What is the minimum size EMT conduit required for three 14 AWG, six 12 AWG, and three 8 AWG conductors? All wires are THHN solid wire.
1 inch
Where an ac system is grounded at any point, the grounded conductors shall be routed with the ungrounded conductors to each service disconnecting means and shall be connected to each disconnecting means grounded conductors terminal or bus for an ac system operating at how many volts?
1,000 volts or less
A motor controller disconnecting means shall be permitted to be out of sight of the controller for motor circuits over how many volts?
1,000 volts, nominal
What is the maximum voltage drop for any branch circuit, separately derived system, operating at 120 volts line-to-line and 60 volts to ground, serving sensitive electronic equipment?
1.5%
Signs and outline lighting system equipment for wet location use, other than listed watertight type, shall be weatherproof and have drain holes not larger than
1/2 inch
EMT shall be securely fastened in place at intervals NOT to exceed which of the following?
10 Feet
A metal underground water pipe used as a grounding electrode shall be in direct contact with the earth for a minimum of how many feet?
10 feet
What is the maximum depth that can be excavated below the bottom members of an excavation support system?
24 inches
Service conductors installed as open conductors or multiconductor cable without an overall outer jacket shall have a minimum clearance of how many feet from porches and balconies?
3 feet
What is the minimum fire rating for electrical vaults housing electrical equipment over 600 volts, nominal?
3 hours Find citation.
What is the power of a 4-ohm resistive load connected to a 120-volt power supply?
3,600 watts OHMS LAW: Power (watts) = Current x Resistance ( P = I V )
High-impedance grounded neutral systems in which a grounding impedance limits the ground fault current to a low value shall be permitted for which type of system?
3-phase ac systems of 480 volts to 1,000 volts
What is the minimum permitted branch circuit overcurrent protection for a 240-volt, 5,000-watt, 60-gallon water heater?
30 Amperes
What is the maximum overcurrent protection for a 10 AWG copper conductor?
30 amperes
What is the required width of the working space in front of electrical equipment with a 22-inch width?
30 inches Find citation
For permanently connected appliances, the branch-circuit overcurrent device shall be permitted to serve as the disconnecting means for appliances rated at not over
300 volt-amperes or 1/8 hp
Which type of conductor or cable is permitted to be used in a wet location?
XHHW
The length of the pull box shall not be less than how many times the outside diameter, over sheath, of the largest shielded or lead-covered conductor or cable entering the box?
48 times
For pool equipment, the disconnecting means for all ungrounded conductors shall be readily accessible and within sight from its equipment and shall be located a minimum of how many feet horizontally from the inside walls of a pool?
5 feet
What is the recommended maximum total voltage drop on both feeders and branch circuits to the farthest outlet?
5%
Lifelines for fall protection shall have a minimum breaking strength of how many pounds?
5,400 pounds
Rod-type grounding electrodes of stainless steel shall have a diameter of not less than which of the following?
5/8 inch
A panelboard for a mobile home shall be rated not less than which of the following?
50 Amperes
One horsepower is equal to how many watts?
746
The conductors, including splices and taps, shall not fill the wireway to more than what percentage of its area?
75%
What is the minimum size solid conductor permitted to be installed in a raceway?
8 AWG
A 3-hp pump is installed 220 feet from the 220-volt main service. What is the voltage drop when using 12 AWG solid wire?
8.8 volts
Temporary electric power and lighting installations for holiday decorative lighting shall be permitted for a period not to exceed how many days?
90 days
The storage batteries used as a source of power for emergency systems shall be of suitable rating and capacity to supply and maintain the total load for a minimum of how long?
90 minutes
A feeder supplies a continuous lighting load of 45 amperes and a single motor load of 30 amperes. What is the ampere rating of the feeder?
94 Amperes
What is an askarel?
A group of nonflammable synthetic chlorinated hydrocarbons used as electrical insulating media polychlorinated biphenyl (PCB)
Type MI conductors shall NOT be composed of which material?
Aluminum
A system that is connected to establish electrical continuity and conductivity is considered to be which of the following?
Bonded
When the disconnecting means of a transformer is located remotely it must be
Lockable
When installed in the same cable tray, cables operating at over 600 volts shall be of which type?
MC cable
A fitting is a part of a wiring system that is intended primarily to perform which type of function?
Mechanical
Where an electrical vault is required or specified for conductors and equipment operating at over 600 volts, nominal, the floor when in contact directly with earth shall be constructed in what manner?
Minimum of 4 inch thick concrete
For electric space heating cables, which color of lead wire is used to indicate a circuit voltage of 240 volt, nominal?
Red
When combination surface metallic raceways are used for both signaling and for lighting and power circuits, the different systems shall be run in separate compartments. Which is NOT an acceptable means of identifying by the interior finish of the different systems?
Tagging
ENT shall not be
Threaded
A minimum of how many threads needs to be engaged if machine screws are used to fasten bonding jumpers?
Two
Which type of surge protection device is permanently connected and intended for installation between the secondary of the service transformer and the line side of the service disconnect overcurrent device?
Type 1 Surge Protector
In which application is the installation of NM cable permitted?
Type III construction
Which type of service-entrance cable has a flame-resistant and moisture resistant covering?
Type SE
Define: The greatest root-mean-square (effective) difference of potential between any two conductors of a circuit.
Voltage
What is the formula for calculating power (watts)?
Watts is equal to Amps x Volts R x I
What part of a bulk storage plant is classified as Class 2, Zone 2?
drainage ditches, separators, and impounding basins