NCCR Electrical Practice Test

These questions are part of the practice quiz. Start practicing

• Where should an ammeter be connected in a circuit?
• Percent slip of an induction motor refers to the:
• The NEC guideline for voltage drop is 3%. For a 240-volt system, the minimum circuit voltage is approximately which value?
• Which device’s secondary circuit can produce a dangerously high voltage if opened?
• Voltage is defined as:
• What instrument is used to perform an insulation-resistance test on 480-volt feeder conductors?
• In a sine wave, the number of times per second the identical pattern repeats is known as the
• Which term describes an unintended conducting path between two points in an electrical system?
• If a circuit has 240 V and a resistance of 5 Ω, what is the current?
• Rubber personnel protective insulating equipment must be marked with the appropriate voltage rating and:
• A Type X conduit body has how many conduit entries?
• What is the primary current required to produce a 1.25 A secondary current on a 4000:5 current transformer?
• An electrician reporting to the work area notices that the temporary wiring has been damaged. What should the electrician do?
• Which plan shows the location of structures and equipment on a property?
• What is the standard size system used in the United States for electrical conductors?
• What is the total resistance of a circuit that has a 50-ohm resistor, a 75-ohm resistor, and a 100-ohm resistor in series?
• Which instrument is used to measure current?
• Rubber personnel protective insulating equipment must be marked with voltage rating and what other information?
• What does a wattmeter indicate?
• What is a dropout plate?
• Where is the easiest place to reverse the rotation of a 3-phase motor?
• Which NEMA enclosure type is designed to be watertight and resistant to corrosion?
• The opposition to current flow referred to as?
• In a three-phase panel, standing in front of the equipment, the C phase is located on which side relative to the A phase?
• What is the name of the system of grounding electrodes interconnected by grounding conductors buried in the earth to provide lower resistance?
• A conduit piston (mouse) is used for what application?
• Which term describes a drum used to take the pull rope around when installing heavy cables with a puller?
• Which description best defines a confined space?
• Which of the following is not a correct Ohm's Law formula?
• Horsepower ratings given to electric motors relate to the motor's mechanical output.
• The transformer coils of the primary and secondary share no electrical connection, but current flows through them due to which phenomenon?
• The conducting connection, whether intentional or accidental, between any two components of an electrical system is a
• What does NEC stand for?
• In an AC circuit, which term describes how effectively the circuit uses current to produce useful work?
• Which instrument is used to check insulation resistance on cables?
• In a parallel circuit consisting of four resistors, the total number of independent current paths equals how many?
• An assembly containing two or more insulated conductors and having an overall jacket is known as a
• Verifying the presence or absence of voltage should be performed only by
• What is the unit of electrical current?
• Which statement best describes NEMA 4X enclosures?
• With a circuit of a lagging power factor of 0.5, what should be done?
• Generally, the most ideal conductor is made of which material?
• Reducing the capacitance in a capacitor-start motor results in what effect on starting torque?
• The minimum acceptable DC megohm resistance of a 4,160-volt motor is approximately
• In a 240/120 Three-Phase Delta Four-Wire System, the ungrounded conductor with the higher voltage to ground must be identified with the color:
• The AIC Rating Indicates the Device's Ability to Interrupt Which of the Following?
• Cable markings show all of the following, EXCEPT
• Which action should be taken with damaged extension cords?
• What is the voltage ratio for dual-voltage motors?
• A circuit with a source of 120 volts is connected across four parallel 60 ohms resistors. The current through each resistor is:
• If a 90 degree stub is to be bent using 10 degree segments, how many bends are required?
• What is the name of the tester used to verify phase sequence?
• If a circuit has 15 cycles per 1/4 second, what is its frequency in Hertz?
• The turns ratio of a 3-phase transformer is 115 to 1; with a 13.8 kV primary, what is the approximate secondary voltage?
• Normally, the easiest place to reverse the leads to change the direction of rotation of a 3-phase motor is at the
• In a control switch, which contacts are open in the START position?
• The network of buried conductors that connects grounding electrodes to reduce earth resistance is called a
• In AC circuits, the quantity expressed by volt-amperes corresponds to which of the following?
• The potential across the circuit is 480 volts and the current is 50 amps. What is the resistance?
• Compounds made of porcelain and plastic are used as
• Which NEMA enclosure type is approved for general indoor use and is NOT dust-tight or drip-proof?
• In the circuit described, what is the total current drawn from the source?
• Damaged tools or extension cords should be____.
• What instrument is used to test insulation resistance between heating cable conductors and metallic grounding?
• What is the center-to-center distance for two 30-degree bends in an offset bend with a height of 18 inches?
• The Insulation Thickness of 220 Mils Converts to Approximately How Many Inches?
• Which color code is used to identify the ungrounded conductor with the higher voltage to ground in a 240/120 delta four-wire system?
• Indoor switchgear MUST be stored in a location that protects it from
• In a power cable puller system, which drum is the rope wrapped around?
• Which expression correctly represents electrical power in terms of voltage and current?
• What is the recommended safety practice when using a ladder?
• The device used to prevent moisture from accumulating in hazardous wet locations is called a
• Rubber gloves MUST be electrically tested at MAXIMUM intervals of
• In the event of an emergency where the lockout / tagout device is left secured , who can remove the lockout / tagout device
• What is the source voltage in a circuit that consumes 1200 watts at a current of 5 amps?
• What is the unit of electrical resistance?
• What is the standard time rating for a continuous duty rated electric motor?
• A three-way switch is which type of switch?
• What is the purpose of a Lockout/Tagout System?
• A swivel joint connection in a cable tray installation requires which of the following?
• Which instrument is commonly used to test insulation integrity in electrical equipment?
• Which contact(s) are open when the switch is in the START mode?
• Which category rating would be appropriate for voltage measurements at service equipment in an industrial facility?
• What is the diagram used to show a direct connection from point A to B for conductors?
• Which instrument is used to measure DC voltage?
• Which choice best describes the two types of pushbutton operators typically used in motor controls
• What is the unit of electrical resistance?
• Which interval are rubber insulating gloves tested at?
• A conduit piston (mouse) is used for what application?
• Which of the following best identifies the source for overcurrent device minimum requirements?
• Which symbol represents the overload relay in a schematic diagram?
• A current transformer has a rating of 4000:5; if 1000 amps load is on the primary, the secondary output would produce
• To reverse the rotation of a three-phase motor, you should swap any two T leads.
• Horsepower ratings on electric motors indicate the motor's mechanical output power.
• A ladder tray is characterized by consisting of what?
• Time delay fuses are designed to do what in circuits?
• A dropout plate serves what function in cable tray systems?
• What is the recommended method of attaching self-regulating heating cables to pipes?
• Which contacts are closed in the RUN mode?
• In a high-leg delta system, what is the voltage on the high leg to neutral?
• What is the equivalent resistance of four 60 Ω resistors in parallel?
• In a circuit with four resistors in parallel, how many current paths are available for current flow?
• What connector should be used to splice a 15 kV shielded cable?
• To prevent moisture from accumulating in hazardous wet locations, which device is used?
• For a #8 copper conductor (16,510 cmil) carrying 39 A over 215 feet one-way at 120 V, what is the voltage drop?
• The outer covering on a liquid-tight flexible metal conduit is used for
• The conductors used to connect the system grounded conductor or the equipment to a grounding electrode or to a point on the grounding
• In an AC circuit, the volt-amperes measurement is the same as which quantity according to the material?
• If a conductor carries 2 A and has a resistance of 5 ohms, what is the voltage across it?
• Which of these is used as a guide to assist cables entering a conduit?
• The Equipment Grounding Conductor is used to interconnect and bond:
• Which statement about class 0 rubber protective equipment is correct?
• Which component protects wires from the sharp edges of conduit and is joined to the metal?
• In a sine wave, the frequency describes cycles per second.
• A conductor with 220 mils of insulation would have an insulation thickness of
• A drill motor breaks down during an installation. What should be done?
• If a circuit breaker is marked Al/Cu, what does this indicate?
• Which inscription on a circuit breaker indicates suitability for both copper and aluminum conductors?
• Which type of conductor is approved for installation in a wet location?
• Which type of transformer core assembly offers low resistance to magnetic lines of force?
• Time delay fuses are most commonly used in circuits subject to what type of current?
• To reverse the rotation of a three-phase motor, which action should be taken?
• For a fixed number of poles in an AC motor, which factor determines its speed?
• Copper and silver are examples of what electrical component category?
• When is it required that conductors be derated?
• According to NEC Article 240.4(D)(5), 12 AWG copper shall be protected against overcurrent by a device with a maximum ampacity of
• IEC style contactor coils are marked with the labels of
• What type of conduit can be safely used in a corrosive environment?
• Copper is generally considered the most ideal conductor for electrical wiring. Which material is it?
• Wire connectors labeled with only the wire size should ONLY be used with what type of conductors?
• What is the minimum pull box length for a 2 inch conduit run when conductors are pulled straight?
• When installing more than one ground rod, the MINIMUM spacing between rods?
• Which classification describes locations where combustible fibers may be present?
• What type of conduit body is characterized by a threaded straight hub on each end?
• Which arrangement is recommended when multiple #2 AWG conductors are pulled together on a fish tape?
• A drawing showing a point A to point B hookup of conductors is called a
• What is the minimum burial depth for bare copper conductor?
• To measure DC voltage with proper polarity, how should the voltmeter be connected?
• A Type X conduit body has how many conduit entries?
• The resistor alloy heating element used in power-limiting heating cables has a:
• In hazardous locations where metal conduit is required, the conduit MUST be threaded with
• For a current transformer rated 4000:5, what is the secondary current when the primary current is 2000 amps?
• An insulated type 600 volt crimp terminal for a 12-10 AWG is typically identified by which color code?
• Before using a multimeter to check voltage on a breaker, you should:
• Lockout/tagout procedures are designed to prevent which situation during maintenance?
• According to the NEC, the minimum circuit operating voltage for a 240-volt circuit with a 3% voltage drop is approximately what value?
• Which color code identifies a crimp terminal for 12-10 AWG used with 600 V insulation?
• Regarding ground ring installations, which statement is true?
• Which statement about connecting a voltmeter to a DC circuit is true?
• Materials made of copper or silver are considered:
• PVC conduit, fittings, and connectors are manufactured in sizes up to what maximum size?
• A 10-inch offset at 30 degrees is being made. What is the distance between center-to-center bends?
• For a high-voltage shielded cable splice, which connector type is recommended?
• The AIC Rating of an Overcurrent Protection Device Represents Its:
• Which option correctly describes the effect of increasing starting torque in a capacitor-start motor?
• Which Statement Best Describes the Auxiliary Holding Contact on a NEMA Starter?
• In typical cable markings, which attribute is not specified?
• What type of bend is used to change conduit elevation to clear an obstruction and then return to the original elevation?
• A ladder tray is designed with two parallel rails connected by what element?
• When terminating feeders to the main switchgear, the feeders must be braced to withstand
• Which category rating would a meter need to have to take voltage readings at the service switchgear of an industrial facility?
• Which of the following is not a reason why electrical systems must be grounded?
• Which conductor is specifically identified as the path from the system's grounding conductor to a grounding electrode?
• What is insulating tape?
• What is the voltage rating for class 0 rubber protective equipment?
• An electrical room involving combustible dust would have explosive mixtures develop if the dust collection system failed. What would be the hazardous classification for this room?
• Which connecting device is used to join conductors and is commonly identified as a split bolt?
• The opposing force to a flow of alternating current is called
• The NEC requires conduit and fittings installed in hazardous locations to be wrench-tight with a minimum of how many engaged threads?
• Which type of raceway would you avoid in areas subject to severe damage?
• Where is the type and size of overcurrent protection specified?
• Which instrument is commonly used to perform an insulation-resistance test on electrical feeders?
• Relays, solenoids, and transformers are examples of component devices that rely on:
• The wattage output of series resistance heating cables depends on the total circuit length and:
• Which test equipment can be used to test the condition of insulation in electrical apparatus?
• Which of the following best describes what a sectional drawing shows?
• For a straight pull, the minimum distance to the opposite wall is how many times the trade size of the largest raceway?
• What is a trapeze-type support?
• What protects the wires from the sharp edges of the conduit and is joined to the metal?
• Which drawing type shows the location of structures and equipment on a property?
• What is the dimension of the generator load conduit entry area if we plan for bottom entry?
• According to NEC, when viewing the switchboard from the front, where is the C phase located relative to the A phase?
• What is the minimum length of bare copper conductor in a ground ring?
• In an AC circuit the total opposition to the flow of current is termed
• Which type of transformer has its windings connected in series?
• If an analog voltmeter is connected to a 24 V DC circuit with the polarity reversed, what reading will occur?
• In schematics, the symbol OL denotes which component?
• In the offset problem, what is the distance between the center lines if the offset is 10 inches at 30 degrees?
• Which raceway is NOT suitable to service where exposed to severe damage?
• What is the minimum length pull box that can be placed in a 2 inch conduit run where the conductors will be pulled straight?
• What is the standard unit for measuring the cross-sectional area of a wire?
• In a series circuit, how is the total resistance determined?
• Which unit is used to measure the cross-sectional area of a conductor?
• An Auxiliary Holding Contact (Seal-In) on a typically NEMA starter is indicated by the terminal marking:
• All parts of metal cable tray must be bonded together and?
• The number of wraps on a capstan indicates what?
• The type of mounting used for lighting fixtures is indicated in the
• What two purposes does a measuring tape used inside conduit serve?
• A megger will be used to check an in-service cable. The Electrician MUST be sure that the circuit is:
• When climbing a ladder, you should face the ladder and
• PVC conduit, fittings and connectors range in size from ½ inch to:
• Which classified location indicates combustible dust is always present?
• The NEC allows copper busbars to carry 1000 amps per square inch. If a bus bar measures 1/4 inch by 2 inches, how many amps is this bar allowed to carry?
• Which instrument is used to verify the direction of alternating current phases in a multi-phase electrical system?
• Which instrument measures current in an electrical circuit?
• A dangerously high voltage is produced when someone opens the secondary circuit of a
• Which conduit bend is used to change elevation to clear an obstruction and then return to the original elevation?
• In a subpanel, the neutral bus is isolated from the grounded bus.
• In dual-voltage motor configurations, the high-to-low voltage ratio is what?
• What is used to make a slight change in elevation in a cable tray system?
• A drawing that shows the height of an object but not depth is called a
• Which of these is pulled through a raceway to test for obstructions before a cable pull?
• Before verifying that a circuit has been de-energized, which safety step must be performed first?
• 'Live-dead live' test is used to:
• A NEMA type ______ enclosure offers only protection against incidental contact.
• Which of the following is NOT an acceptable grounding electrode for a service grounding electrode system?
• The panelboard schedule provides information about which of the following?
• A drawing that shows the height of an object, but not the depth is a(n):
• Which two terminal designations mark IEC style contactor coils?
• Electrical lockout/tagout procedures are designed to keep:
• Which phrase describes the two common pushbutton operators used in motor control?
• Which principle underpins the operation of relays, solenoids, and transformers?