NASCLA Journeyman Electrician Exam Questions

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181.

What is the minimum separation of conductors from an intrinsically safe system within an intrinsically safe enclosure from any nonintrinsically safe circuit conductors within that enclosure?

  • 50 mm (2 in)

  • 25 mm (1 in)

  • 38 mm (1½ in)

  • 75 mm (3 in)

Correct answer: 50 mm (2 in)

Intrinsically safe systems, within enclosures is where you will find this answer.

This condition will arise where conductors originating outside the hazardous location are connected to equipment within the hazardous location. Where the enclosure is required to meet intrinsically safe system requirements, there could be mixed wiring as described. Proper electrical designs can avoid this, but if they do not or cannot, this is the requirement.

182.

When electrons are forced to change to a lower energy state, photons can be produced. What common electrical devices use this operating principle?

  • Sodium and mercury vapor lights

  • Solar cells

  • Photovoltaic

  • Photocondutive

Correct answer: Sodium and mercury vapor lights

Light particles are photons, which are pure energy. Producing electricity from light involves the use of these particles. It is in these vapor-filled lights that the current flow to them is used to change the electrons in the vapor to a lower energy state, thus producing light. 

These devices may include a capacitor in their wiring to initially boost the current or they slowly light (heat) up. 

The other options are related to the use of photons, but involve other principles.

183.

Compliance with the NEC and proper maintenance results in an installation that is essentially free from hazards but not necessarily efficient, convenient, adequate for good service or which of the following?

  • Future expansion of electrical use

  • In accordance with OSHA

  • Required by the Authority Having Jurisdiction

  • Cost-effective for the project budget

Correct answer: Future expansion of electrical use

Adequacy is addressed in Article 90 (B). Here the Code clarifies four issues the Code is not designed or adequate to address. Electricians are responsible for efficiency, convenience, good service, and expansion. Consideration should always be given to the future expansion of the electrical system. While future expansion may be unlikely in some installations, where this consideration is given, it can be very cost-effective for future additions, alterations, or designs when done during initial construction. It is good practice to ask yourself: What would I do if I was the electrician coming back to this job?

184.

How are grounded conductors of service-entrance conductors to be installed if the service-entrance conductors are installed in parallel?

  • In parallel

  • In any raceway

  • By phase

  • In a separate raceway

Correct answer: In parallel

This is about parallel conductors in more than one raceway. And just as important is the grounding of service-supplied ac systems. 

If service conductors are run in parallel, this requires neutrals to be run in parallel too. You do end up with extra, but it is required. There are possible correction factors for the neutral with a size minimum of 1/0 AWG. 

In any raceway, by phase, and in a separate raceway are wrong, but they are options people suggest.

185.

What is a change to prints or specifications before bids are opened known as?

  • Addenda

  • Change order

  • As-builts

  • Revision

Correct answer: Addenda

Addendas are often changes the architect has received from the client. These are very important to the bid process. Bids can be off by a lot if an addenda is missing.

186.

A box, cable, or raceway cannot be installed in a concealed location where a metal-corrugated, sheet decking-type roof is used. You are installing a raceway in an exposed location where this roofing is used.

What distance from the material must you maintain?

  • 38 mm (1 1/2 in)

  • 32 mm (1 1/4 in)

  • 48 mm (2 in)

  • 76 mm (3 in)

Correct answer: 38 mm (1 1/2 in)

The first need is to identify roof decking. The second is regarding physical damage to wiring methods. This type of corrugated roofing uses longer nails. The distance must be increased from that of most other installations.

187.

Is the neutral conductor in a 3-wire flex cable that carries only the unbalanced current from two phases of a 4-wire, 3-phase, wye-connected system considered to be a current-carrying conductor?

  • Yes, the neutral conductor carries only the unbalanced current resulting from the phase differences.

  • Yes, the neutral carries unbalanced current, but not necessarily the same current as each of the phase conductors.

  • No, the presence of flex sheathing does not influence whether the neutral carries unbalanced current.

  • No, it does not carry any current under balanced load conditions.

Correct answer: Yes, the neutral conductor carries only the unbalanced current resulting from the phase differences.

In a 3-phase, 4-wire, wye-connected system, the neutral conductor is essential for carrying the net unbalanced current arising from the phase-to-neutral loads. This can vary depending on the balance and nature of the loads connected to each phase. Under purely balanced load conditions, the neutral would ideally carry no current. This scenario is specifically covered under guidelines and standards concerning ampacity calculations for flex cables, taking into account the specific characteristics and requirements of neutral conductors in wye-connected systems.

188.

Which of the following is defined as an organization, office, or individual responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure?

  • Authority Having Juristiction

  • Construction Industries Board

  • Fire marshall

  • County inspector

Correct answer: Authority Having Jurisdiction

The Authority Having Jurisdiction (AHJ), as used in NFPA documents, has broad application. Jurisdictions and agencies vary, as do their responsibilities. Where public safety is the primary consideration, the AHJ may be local, regional, state, or federal. At times, property owners are their own AHJ. It is most often city or county inspectors and fire marshalls. The other listed options may be an AHJ but are not the definition of an AHJ.

189.

How many circuits can feed a multipole, general purpose snap switch?

  • One

  • Two

  • Three

  • Four

Correct answer: One

There are four items to identify in this question:

  • Equipment for general use
  • Switches
  • Accessibility and grouping 
  • Multipole snap switches

This is the order of items in the Code, but items may be identified in any order throughout the question. We all think differently. Then, recognize the priority of each item in the Code. This should lead you to your answer.

These push button switches are designed as one, two, and three circuit switches. Two and three circuit switches must be both listed and marked as such.

190.

What is the ratio of the maximum demand of a system, or part of a system, to the total connected load of a system or the part of the system under consideration?

  • Demand factor

  • Varying duty

  • Continuous load

  • Periodic duty

Correct answer: Demand factor

Demand factor relates to load expressed in amps. The main consideration in each of the other terms is its load. The characteristics of some of these loads cause different considerations. These considerations will then play a role in determining demand factors. The details of these definitions, too numerous to list here, should be reviewed side by side in the Codebook. 

For electrical licensing exams, first understand NEC definitions found in Article 100. Electricians must then apply the definitions to the specific conditions and applications of the electrical installations and functions at hand. While definitions do not change, conditions, applications, installations, and functions are variables that change quite often. Electricians must determine these variables to properly apply definitions. At times there are more variables than mentioned here. See Section 2 (xxx.2) of other articles for possible additional definitions.

191.

When there is an orange triangle on the front of an outlet, what does the receptacle have the means to reduce?

  • Electromagnetic interference

  • Harmonics

  • Neutral potential

  • Circuit failure

Correct answer: Electromagnetic interference

This marking is an isolated ground receptacle. Receptacles are found under equipment for general use.

This marking is on the receptacle itself and not just the cover. You may see older models that are orange with a green triangle on the orange receptacle and receptacle cover.

192.

A branch circuit you will install in a 277-volt system will have a combination of continuous and noncontinuous loads on it. Branch circuit conductor sizes are required to have an ampacity not less than the noncontinuous load, plus what percent of the continuous load?

  • 125%

  • By a factor of 1.73

  • 80%

  • 85%

Correct answer: 125%

Branch circuits, conductors, and a general parameter are the main issues in this question. 210.19(A)(1)(a) addresses minimum conductor ampacity for which several reference bases are listed.

The 125% is an industry standard that applies to the ampacity of most installations. This is in accordance with 310.14. 

The other options are random demand factors for other calculations. 1.73 is a constant for transformer and phase to phase calculations. Remember 1.73, we use it inversely for different calculations.

193.

Electrical equipment capable of being reached for operation, renewal, and inspection, is referred to as?

  • Accessible

  • Exposed

  • Readily accessible

  • Concealed

Correct answer: Accessible

Here, the term accessible only applies to equipment. Where the term applies to wiring, the definition changes and relates more to building structure and finishes. Both the answer and the other options primarily pertain to the final evaluation of equipment and wiring, but may be evaluated differently in various electrical installations. 

For electrical licensing exams, first understand all NEC definitions found in Article 100. They are unique to the Code. Several key terms are separately defined where they are applied differently. Electricians must apply the correct definition to the specific application and condition of the electrical installations and/or functions at hand. While definitions do not change, conditions, applications, installations, and functions are all variables that bring different evaluations to light. Electricians make these evaluations to properly apply definitions. At times there are more variables than mentioned here. Also, see Section 2 (xxx.2) of articles for additional definitions supplied for that article.

194.

What is a protection technique utilizing stationary gas detectors in industrial establishments?

  • A combustible gas detection system

  • Encapsulation “m”

  • Flameproof “d”

  • Hermetically sealed

Correct answer: A combustible gas detection system

The NEC definition of a combustible gas detection system is a protection technique utilizing stationary gas detectors in industrial establishments.

Hazardous locations have related definitions that are not hard to learn. There are identifiers within them that, once recognized, will help you find the answers in a short amount of time.

It’s about identification, not memorization.

The other options are defined separately. If you do not know them, review them.

195.

What is the equipment that controls dc voltage and/or dc current, and that is used to charge a battery or other energy storage device called?

  • Charge controller

  • Class 3 circuit

  • Class 2 circuit

  • Controller

Correct answer: Charge controller

This is the NEC definition for a common battery charger. A computer UPS could be considered a device. Whether used commercially or industrially, a UPS is considered equipment (or a system) which should all have a charge controller regulating the input. 

A controller governs various power requirements delivered to various apparatus. Class circuits are power limiting circuits with several other parameters. Therefore, these may be but are not necessarily involved.

For electrical licensing exams, first understand NEC definitions found in Article 100. Electricians must then apply the definitions to the specific conditions and applications of the electrical installations and functions at hand. While definitions do not change, conditions, applications, installations, and functions are variables that change quite often. Electricians must determine these variables to properly apply definitions. At times there are more variables than mentioned here. See Section 2 (xxx.2) of other articles for possible additional definitions.

196.

What does the electrical grounding system serve as to an electrical service or distribution system supplying electrical energy to a structure?

  • The foundation

  • Code requirements

  • The bonding system

  • Protection from electrical hazards

Correct answer: The foundation

No different than a building that needs a solid foundation, every electrical system is built on the foundation of an effective and efficient grounding system.

The other options are or may be true, but do not satisfy the reference.

197.

The bonding conductor or grounding electrode in one family dwelling unit is required to be as short as practicable and not to exceed?

  • 6.0 m (20 ft)

  • 8.0 m (26 ft)

  • 4.0 m (14 ft)

  • 5.0 m (16 ft)

Correct answer: 6.0 m (20 ft)

Here, we find bonding conductors addressed under length. This is the order: general, grounding conductors, length.

198.

What is the name given to the opposition to current offered by the internal structure of the particular conductive material to the movement of electricity through it, to the maintenance of current in them?

  • Resistance

  • Capacitance

  • Inductance

  • Counter-electromotive force

Correct answer: Resistance

Most electricians understand resistance is the opposition to current. Here, Soares points out “to the maintenance of current in them”. This is an important point. This causes an immediate set of reactions and inverse reactions. Capacitance, inductance, and thus, counter-EMF, can play a role in the reduced effectiveness of overcurrent protection devices. Current can spill into the neutral and ground causing issues with these devices. See Soares definition.

The other options are related to and involved, but do not satisfy the answer.

199.

What class are locations in which flammable gasses, flammable liquid-produced vapors, or combustible liquid-produced vapors are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures?

  • Class I

  • Class II

  • Class III

  • Class IV

Correct answer: Class I

This is a general definition of a Class I location. Other Class I locations are those that are specified by two pages of criteria following Article 500.5(B). 

Other questions will consider what locations may include.

200.

Unless otherwise required or permitted by the Code, completed wiring installations are required to be free from connections to ground and what other two electrical conditions?

  • Short circuits and ground faults

  • Nicks and cuts 

  • Breaker trips and fire ignition

  • Fault current and overcurrent

Correct answer: Short circuits and ground faults

This question is about wiring integrity addressed in Article 100. This integrity means all circuits are free from short circuits, ground faults, or any connections to ground, unless the ground is required or permitted by the Code.

All other options are electrical conditions but are often the cause of, or the result of, short circuits, ground faults or improper grounding.