Prompt stringlengths 16 335 | Text stringlengths 25 3.89k | Rejected Text stringlengths 1 545 ⌀ |
|---|---|---|
How should the equipment grounding conductor contacts of receptacles and cord connectors be grounded? | NEC Section 406.4_(C) requires that these contacts shall be grounded by connection to the equipment grounding conductor of the circuit supplying the receptacle or cord connector.\n - [NEC Section 406.4_(C)](https://2023.antflix.net#406.4_(C)): "The equipment grounding conductor contacts of receptacles shall be connecte... | NEC Section 406.4_(C) requires that these contacts shall be grounded by connection to the equipment grounding conductor of the circuit supplying the receptacle or cord connector. |
When existing nongrounding types of receptacles need replacing, what type of receptacle must be used? | NEC Section 406.4(D)(2) requires that existing nongrounding types of receptacles be replaced with the grounding type and connected to the equipment grounding conductor. Where a grounding means does not exist in the receptacle enclosure, either a nongrounding or a ground-fault circuit-interrupter type of receptacle must... | NEC Section 406.4(D)(2) requires that existing nongrounding types of receptacles be replaced with the grounding type and connected to the equipment grounding conductor. Where a grounding means does not exist in the receptacle enclosure, either a nongrounding or a ground-fault circuit-interrupter type of receptacle must... |
What precautions must be taken when receptacles are connected to circuits having different voltages, frequencies, or types of current (AC or DC) on the same premises? | NEC Section 406.4_(F) requires that attachment plugs used on such circuits not be interchangeable.\n - [NEC Section 406.4_(F)](https://2023.antflix.net#406.4_(F)): "Receptacles connected to circuits that have different voltages, frequencies, or types of current (ac or dc) on the same premises shall be of such design th... | NEC Section 406.4_(F) requires that attachment plugs used on such circuits not be interchangeable. |
What location requires all 15- and 20-ampere receptacles to be protected with a ground-fault circuit-interrupter? | NEC Section 210.8 requires that all of these areas have receptacles protected with GFCI.\n - [NEC Section 210.8](https://2023.antflix.net#210.8): "A listed Class A GFCI shall provide protection in accordance with 210.8(A) through (F). The GFCI shall be installed in a readily accessible location. Informational Note: See... | NEC Section 210.8 requires that all of these areas have receptacles protected with GFCI. |
Which one of the following is not allowed to supply branch circuits? | NEC Section 210.9 does not allow branch circuits to be derived from autotransformers unless the circuit supplied has a grounded conductor that is electrically connected to a grounded conductor of the system supplying the autotransformer.\n - [NEC Section 210.9](https://2023.antflix.net#210.9): "Branch circuits shall no... | NEC Section 210.9 does not allow branch circuits to be derived from autotransformers unless the circuit supplied has a grounded conductor that is electrically connected to a grounded conductor of the system supplying the autotransformer. |
According to the NEC, what constitutes a bathroom in electrical wiring systems? | NEC Article 100 defines a bathroom as an area including a basin with one or more of the following: a toilet, tub, a urinal, a shower, a bidet. A room with only one fixture does not qualify as a bathroom.\n - [NEC Section ](): "" | NEC Article 100 defines a bathroom as an area including a basin with one or more of the following: a toilet, tub, a urinal, a shower, a bidet. A room with only one fixture does not qualify as a bathroom. |
What is the maximum load allowed by the NEC for cord- or plug-connected load to a 15-ampere receptacle? | NEC Table 210.21_(B)(2) limits the load to 12 amperes when connected to either a 15 or 20 ampere circuit.\n - [NEC Section ](): "" | NEC Table 210.21_(B)(2) limits the load to 12 amperes when connected to either a 15 or 20 ampere circuit. |
What is the maximum load allowed by the NEC for cord- or plug-connected load to a 20-ampere receptacle? | NEC Table 210.21_(B)(2) stipulates 16 amperes as maximum for a 20-ampere receptacle.\n - [NEC Section ](): "" | NEC Table 210.21_(B)(2) stipulates 16 amperes as maximum for a 20-ampere receptacle. |
What is the minimum rating allowed for a single receptacle connected to a branch circuit? | NEC Section 210.21_(B) requires that a single receptacle have a rating no less than the branch circuit.\n - [NEC Section 210.21_(B)](https://2023.antflix.net#210.21_(B)): "No body text available" | NEC Section 210.21_(B) requires that a single receptacle have a rating no less than the branch circuit. |
What is the minimum branch-circuit rating for household electric ranges with a rating of 8.75 kW or more? | NEC Section 210.19(4)(3) requires that branch circuits supplying electric ranges with 8.75 kW or more be rated no less than 40 amperes.\n - [NEC Section 210.19](https://2023.antflix.net#210.19): "Branch-circuit conductors for circuits not exceeding 1000 volts ac or 1500 volts dc shall be sized in accordance with 210.19... | NEC Section 210.19(4)(3) requires that branch circuits supplying electric ranges with 8.75 kW or more be rated no less than 40 amperes. |
What is the minimum rating for heavy-duty lampholders if not of the admedium type? | NEC Section 210.21_(A)(4) requires heavy-duty lampholders to have a rating of not less than 660 watts if of the admedium type and not less than 750 watts if of any other type.\n - [NEC Section 210.21_(A)](https://2023.antflix.net#210.21_(A)): "Where connected to a branch circuit having a rating in excess of 20 amperes,... | NEC Section 210.21_(A)(4) requires heavy-duty lampholders to have a rating of not less than 660 watts if of the admedium type and not less than 750 watts if of any other type. |
When must temporary wiring used on a construction project be removed? | NEC Section 590.3_(D) requires that temporary service be removed immediately upon completion of the construction. The actual time permitted will vary from jurisdiction to jurisdiction, but usually the temporary service is disconnected at the same time the permanent service is connected.\n - [NEC Section 590.3_(D)](http... | NEC Section 590.3_(D) requires that temporary service be removed immediately upon completion of the construction. The actual time permitted will vary from jurisdiction to jurisdiction, but usually the temporary service is disconnected at the same time the permanent service is connected. |
What type of plugs must all temporary 125-volt, single-phase, 15-, 20-, and 30-ampere receptacle outlets be equipped with? | NEC Section 590.6_(A)(1) requires all temporary receptacles to be protected with Ground-fault circuit-interrupters (GFCIs) for the protection of workers on the job.\n - [NEC Section 590.6_(A)](https://2023.antflix.net#590.6_(A)): "Temporary receptacle installations used to supply temporary power to equipment used by pe... | NEC Section 590.6_(A)(1) requires all temporary receptacles to be protected with Ground-fault circuit-interrupters (GFCIs) for the protection of workers on the job. |
What is not a requirement for an intersystem bonding termination device? | required bonding conductors covered in Articles 770 and 830. NEC Article 250.94. The NEC requires a bonding termination point be provided at the service equipment for connecting\n - [NEC Section ](): "" | required bonding conductors covered in Articles 770 and 830. NEC Article 250.94. The NEC requires a bonding termination point be provided at the service equipment for connecting |
What is the minimum size conductor that may be connected in parallel? | larger; comprising each phase, polarity; neutral, or grounded circuit conductor; to be connected in NEC Section 310.10(H)(1) allows aluminum, copper-clad aluminum; or copper conductors; 1/0 or parallel.\n - [NEC Section 310.10](https://2023.antflix.net#310.10): "The conductors described in 310.4 shall be permitted for ... | larger; comprising each phase, polarity; neutral, or grounded circuit conductor; to be connected in NEC Section 310.10(H)(1) allows aluminum, copper-clad aluminum; or copper conductors; 1/0 or parallel. |
When conductors are paralleled, how are they connected? | The ends of two or more conductors are connected to the same lug or terminal at each end of the conductor runs. NEC Section 310.10(H)(1).\n - [NEC Section 310.10](https://2023.antflix.net#310.10): "The conductors described in 310.4 shall be permitted for use in any of the wiring methods covered in Chapter 3 and as spec... | The ends of two or more conductors are connected to the same lug or terminal at each end of the conductor runs. NEC Section 310.10(H)(1). |
Where must AFCIs be installed on all branch circuits? | Section 210.12_(B) has been expanded and requires that all branch circuits supplying outlets in these areas be protected by an arc-fault circuit interrupter: In addition, family rooms, dining rooms; living rooms; parlors, libraries, dens, bedrooms sunrooms, recreation rooms, closets, hallways, or similar rooms or areas... | Section 210.12_(B) has been expanded and requires that all branch circuits supplying outlets in these areas be protected by an arc-fault circuit interrupter: In addition, family rooms, dining rooms; living rooms; parlors, libraries, dens, bedrooms sunrooms, recreation rooms, closets, hallways, or similar rooms or areas... |
What is the temperature adjustment for conductors installed in 2-inch conduit above a roof and exposed to sunlight? | NEC Table 310.15_(B)(3)(c) requires that a 22-degree € (40 F) temperature adjustment adder be applicable ambient temperature. This temperature is applied to the outdoor temperature to determine the 310.15_(B)(2)(b).\n - [NEC Section ](): "" | NEC Table 310.15_(B)(3)(c) requires that a 22-degree € (40 F) temperature adjustment adder be applicable ambient temperature. This temperature is applied to the outdoor temperature to determine the 310.15_(B)(2)(b). |
What is the maximum overcurrent protection allowed on No. 14 AWG copper wire when used in a raceway for branch circuits? | NEC Section 240.4(D)(3) specifies 15 amperes.\n - [NEC Section 240.4](https://2023.antflix.net#240.4): "Conductors, other than flexible cords, flexible cables, and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in 310.14, unless otherwise permitted or required in 240... | NEC Section 240.4(D)(3) specifies 15 amperes. |
What is the maximum overcurrent protection allowed on No. 12 AWG copper wire when used in a raceway for branch circuits? | NEC Section 240.4(D)(5) specifies 20 amperes.\n - [NEC Section 240.4](https://2023.antflix.net#240.4): "Conductors, other than flexible cords, flexible cables, and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in 310.14, unless otherwise permitted or required in 240... | NEC Section 240.4(D)(5) specifies 20 amperes. |
What is the maximum overcurrent protection allowed on No. 10 AWG copper wire when used in a raceway for branch circuits? | NEC Section 240.4(D)(7) specifies 30 amperes.\n - [NEC Section 240.4](https://2023.antflix.net#240.4): "Conductors, other than flexible cords, flexible cables, and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in 310.14, unless otherwise permitted or required in 240... | NEC Section 240.4(D)(7) specifies 30 amperes. |
Which locations prohibit the use of Type MI cable? | Highly corrosive conditions can cause deterioration of the metal jacket. NEC Section 332.12(2).\n - [NEC Section 332.12](https://2023.antflix.net#332.12): "Type MI cable shall not be used under the following conditions or in the following locations: In underground runs unless protected from physical damage, where neces... | Highly corrosive conditions can cause deterioration of the metal jacket. NEC Section 332.12(2). |
What is the allowable ampacity of a 600MCM copper conductor type TW? | Because the NEC is used internationally; lower and higher ambient temperatures were added to provide factors for colder and warmer climates. NEC Table 310.15_(B)(16) (formerly Table 310.16).\n - [NEC Section ](): "" | Because the NEC is used internationally; lower and higher ambient temperatures were added to provide factors for colder and warmer climates. NEC Table 310.15_(B)(16) (formerly Table 310.16). |
Where can splices in an ENT system be made? | NEC Section 362.56 specifies that splices and taps may be made only in junction boxes, Outlet boxes or conduit bodies: Also see NEC Article 300.15.\n - [NEC Section 362.56](https://2023.antflix.net#362.56): "Splices and taps shall be made only in accordance with 300.15." | NEC Section 362.56 specifies that splices and taps may be made only in junction boxes, Outlet boxes or conduit bodies: Also see NEC Article 300.15. |
Why should dissimilar metals in contact anywhere in the system be avoided? | NEC Section 344.14 requires protection of metal conduits from corrosive influences.\n - [NEC Section 344.14](https://2023.antflix.net#344.14): "Where practicable, dissimilar metals in contact anywhere in the system shall be avoided to eliminate the possibility of galvanic action. Stainless steel and aluminum fittings a... | NEC Section 344.14 requires protection of metal conduits from corrosive influences. |
Where shall Type MC (metal-clad) cable not be used? | NEC Section 330.12(2) does not permit Type MC cable to be used in areas where corrosive conditions exist unless the metallic sheath or armor is resistant to the conditions, or is protected by material resistant to the conditions.\n - [NEC Section 330.12](https://2023.antflix.net#330.12): "Type MC cable shall not be use... | NEC Section 330.12(2) does not permit Type MC cable to be used in areas where corrosive conditions exist unless the metallic sheath or armor is resistant to the conditions, or is protected by material resistant to the conditions. |
Where may Type NMC cable be used? | NEC Section 334.10_(B) permits Type NMC cable to be installed in dry or moist locations.\n - [NEC Section 334.10_(B)](https://2023.antflix.net#334.10_(B)): "Type NMC cable shall be permitted as follows: For both exposed and concealed work in dry, wet, damp, or corrosive locations, except as prohibited by 334.10(3)In ou... | NEC Section 334.10_(B) permits Type NMC cable to be installed in dry or moist locations. |
In what areas may Power and control tray cable (Type TC) not be used? | NEC Section 336.12(1) prohibits the use of Type TC cable in areas where the cable will be exposed to physical damage.\n - [NEC Section 336.12](https://2023.antflix.net#336.12): "Type TC tray cable shall not be installed or used as follows: Installed where it will be exposed to physical damageInstalled outside a raceway... | NEC Section 336.12(1) prohibits the use of Type TC cable in areas where the cable will be exposed to physical damage. |
What is the minimum size IMC conduit allowed for electrical systems for building construction? | NEC Section 342.20_(A) prohibits the use of IMC conduit smaller than trade size 1/2 inch.\n - [NEC Section 342.20_(A)](https://2023.antflix.net#342.20_(A)): "IMC smaller than metric designator 16 (trade size 1/2) shall not be used." | NEC Section 342.20_(A) prohibits the use of IMC conduit smaller than trade size 1/2 inch. |
What is the maximum continuous load (in amperes) that can be used on a 240-volt; 20-ampere circuit assembly together with its overcurrent device that is listed for continuous operation at 100 percent of its rating when supplied by two No. 12 AWG conductors with THW insulation? | A circuit supplied by an assembly together with its overcurrent device that is listed for continuous operation at 100 percent of its rating may carry the full load. Since No. 12 conductor is rated at 20 amperes, the maximum current permitted for continuous loads is 20 amperes. NEC Section 210.20_(A), Exception.\n - [NE... | A circuit supplied by an assembly together with its overcurrent device that is listed for continuous operation at 100 percent of its rating may carry the full load. Since No. 12 conductor is rated at 20 amperes, the maximum current permitted for continuous loads is 20 amperes. NEC Section 210.20_(A), Exception. |
What is an AFCI? | NEC Article 100 Definitions defines an arc-fault circuit-interrupter as a device intended to provide functioning to de-energize the circuit when an arc fault is detected. Section 210.12_(A) provides the protection from the effects of arc faults by recognizing characteristics unique to arcing and by requirements.\n - [N... | NEC Article 100 Definitions defines an arc-fault circuit-interrupter as a device intended to provide functioning to de-energize the circuit when an arc fault is detected. Section 210.12_(A) provides the protection from the effects of arc faults by recognizing characteristics unique to arcing and by requirements. |
Where a cable or raceway wiring method is installed through holes bored in wooden floor member, what protection must be provided? | NEC Section 300.4_(A)(1) requires steel plates or bushings for protection.\n - [NEC Section 300.4_(A)](https://2023.antflix.net#300.4_(A)): "No body text available" | NEC Section 300.4_(A)(1) requires steel plates or bushings for protection. |
What is the required minimum thickness of the plate when steel plates are used to protect a cable or wiring method? | NEC Section 300.4_(A)(1) requires a minimum thickness of 1/16 inch.\n - [NEC Section 300.4_(A)](https://2023.antflix.net#300.4_(A)): "No body text available" | NEC Section 300.4_(A)(1) requires a minimum thickness of 1/16 inch. |
Which of the following do not require GFCI protection for all 125-volt, 15- and 20-ampere receptacles? | Outlets in basements supplying a permanently-installed fire or burglar alarm, need not be GFCI protected. NEC Section 210.8 Exception; Outlets in unfinished basements, storage areas, work areas and the like.\n - [NEC Section 210.8](https://2023.antflix.net#210.8): "A listed Class A GFCI shall provide protection in acco... | Outlets in basements supplying a permanently-installed fire or burglar alarm, need not be GFCI protected. NEC Section 210.8 Exception; Outlets in unfinished basements, storage areas, work areas and the like. |
What must be installed at or near equipment requiring servicing such as HVAC equipment in attics or crawl spaces? | NEC Section 210.70_(C) requires at least one switch-controlled lighting outlet so that service personnel light prior to entering the work area can turn on.\n - [NEC Section 210.70_(C)](https://2023.antflix.net#210.70_(C)): "For attics and underfloor spaces, utility rooms, and basements, at least one lighting outlet con... | NEC Section 210.70_(C) requires at least one switch-controlled lighting outlet so that service personnel light prior to entering the work area can turn on. |
Where must the switch be located according to NEC Section 210.70_(C) when servicing equipment in attics or crawl spaces? | The switch must be located at the usual point of entry to the area.\n - [NEC Section ](): "" | The switch must be located at the usual point of entry to the area. |
What is the maximum size of rigid metal conduit allowed for electrical construction? | NEC Section 344.20_(B) prohibits the use of conduit larger than 6 inches.\n - [NEC Section 344.20_(B)](https://2023.antflix.net#344.20_(B)): "RMC larger than metric designator 155 (trade size 6) shall not be used. Informational Note: See 300.1(C) for the metric designators and trade sizes. These are for identification ... | NEC Section 344.20_(B) prohibits the use of conduit larger than 6 inches. |
What does the NEC define as an "unfinished basement"? | NEC Section 210.8(4)(5) defines 'unfinished basement' as portions or areas of the basement not intended as habitable rooms and limited to storage areas, work areas, and the like.\n - [NEC Section 210.8](https://2023.antflix.net#210.8): "A listed Class A GFCI shall provide protection in accordance with 210.8(A) through ... | NEC Section 210.8(4)(5) defines 'unfinished basement' as portions or areas of the basement not intended as habitable rooms and limited to storage areas, work areas, and the like. |
Where does NEC Section 210.8(4)(3) require ground-fault circuit-interrupter protection for residential outdoor receptacles? | NEC Section 210.8(4)(3) requires all residential outdoor receptacles to be provided with GFCI protection.\n - [NEC Section 210.8](https://2023.antflix.net#210.8): "A listed Class A GFCI shall provide protection in accordance with 210.8(A) through (F). The GFCI shall be installed in a readily accessible location. Inform... | NEC Section 210.8(4)(3) requires all residential outdoor receptacles to be provided with GFCI protection. |
According to NEC Section 210.50_(C), how many feet away must appliance receptacle outlets be installed from the intended location of the appliance? | NEC Section 210.50_(C) requires that the outlet be installed within 6 feet of the intended location of the appliance.\n - [NEC Section 210.50_(C)](https://2023.antflix.net#210.50_(C)): "Appliance receptacle outlets installed in a dwelling unit for specific appliances, such as laundry equipment, shall be installed withi... | NEC Section 210.50_(C) requires that the outlet be installed within 6 feet of the intended location of the appliance. |
What is the purpose of all electric services? | All electric services are provided for the purpose of delivering electrical energy from the supply system to the wiring system on the premises served.\n - [NEC Section ](): "" | All electric services are provided for the purpose of delivering electrical energy from the supply system to the wiring system on the premises served. |
What is the Service lateral defined as? | Service lateral: The underground conductors through which service is supplied between the power company's distribution facilities and the first point of their connection to the building or area service facilities.\n - [NEC Section ](): "" | Service lateral: The underground conductors through which service is supplied between the power company's distribution facilities and the first point of their connection to the building or area service facilities. |
What are the basic components of an electric service? | High-voltage lines, Pole, Service head, Transformer, Service drop, SE cable, SE cable straps, Branch circuits to lights, receptacles, etc., Cable connector, Main disconnect, Circuit breakers, Electric meter, Main panelboard.\n - [NEC Section ](): "" | High-voltage lines, Pole, Service head, Transformer, Service drop, SE cable, SE cable straps, Branch circuits to lights, receptacles, etc., Cable connector, Main disconnect, Circuit breakers, Electric meter, Main panelboard. |
What are the power company pole and the building or other support used for the purpose called? | The overhead conductors, through which electrical service is supplied; between the last\n - [NEC Section ](): "" | The overhead conductors, through which electrical service is supplied; between the last |
What is the wiring system of the premises served called? | The conductors and equipment for delivering electric energy from the power company to the\n - [NEC Section ](): "" | The conductors and equipment for delivering electric energy from the power company to the |
What are the underground service lateral and the main disconnecting device in a building known as? | The conductors between the point of termination of the overhead service drop or\n - [NEC Section ](): "" | The conductors between the point of termination of the overhead service drop or |
What is the necessary equipment connected to the load end of the service conductors to a building or other structure and intended to constitute the main control and cutoff of the supply known as? | Service equipment\n - [NEC Section ](): "" | Service equipment |
What are the underground conductors through which service is supplied between the power company's distribution facilities and the first point of their connection to a building or area service facilities located at the building or other support used for the purpose known as? | Underground electric services frequently emanate from a pad-mounted transformer; but the service conductors run underground. From this point, the conductors can be run down a power pole in conduit to a point underground to the building NEC Article 100 Definitions See Figure 4-2.\n - [NEC Section ](): "" | Underground electric services frequently emanate from a pad-mounted transformer; but the service conductors run underground. From this point, the conductors can be run down a power pole in conduit to a point underground to the building NEC Article 100 Definitions See Figure 4-2. |
In a balanced three-phase, 4-wire system, what happens to the current in the neutral conductor? | The grounded or neutral conductor carries only the unbalanced load. If, say, a single-phase, 120/240-and 80 amperes on phase B, the neutral would carry only the difference between the current in phase A and that in phase B.\n - [NEC Section ](): "" | The grounded or neutral conductor carries only the unbalanced load. If, say, a single-phase, 120/240-and 80 amperes on phase B, the neutral would carry only the difference between the current in phase A and that in phase B. |
On a 240-volt, single-phase, 3-wire system, what role does the neutral conductor play? | The neutral conductor will never carry current larger than the difference between the current in the two ungrounded conductors.\n - [NEC Section ](): "" | The neutral conductor will never carry current larger than the difference between the current in the two ungrounded conductors. |
What unit is used to measure current? | Current is the rate at which electricity flows through a conductor. The unit of measurement is the ampere.\n - [NEC Section ](): "" | Current is the rate at which electricity flows through a conductor. The unit of measurement is the ampere. |
What is the minimum allowable current rating of 3-wire service-entrance conductors for a one-family dwelling? | 100 amperes\n - [NEC Section ](): "" | 100 amperes |
What is the minimum allowable current rating of 3-wire service-entrance conductors for a one-family dwelling with an initial net computed load of 10 kVA or more? | 100 amperes\n - [NEC Section ](): "" | 100 amperes |
What is the smallest copper wire size allowed for service-entrance conductors? | No. 8 AWG\n - [NEC Section ](): "" | No. 8 AWG |
What is the smallest grounded or neutral conductor for an electric service using 1100 kcmil copper conductors? | The smallest grounded or neutral conductor for an electric service using 1100 kcmil copper conductors is 2/0 copper.\n - [NEC Section ](): "" | The smallest grounded or neutral conductor for an electric service using 1100 kcmil copper conductors is 2/0 copper. |
What is the minimum size electric service required for a single-family dwelling? | The minimum size electric service required for a single-family dwelling is 100 amperes.\n - [NEC Section ](): "" | The minimum size electric service required for a single-family dwelling is 100 amperes. |
What is the name given to a system or circuit conductor that is intentionally grounded? | The name given to a system or circuit conductor that is intentionally grounded is Grounded or neutral conductor.\n - [NEC Section ](): "" | The name given to a system or circuit conductor that is intentionally grounded is Grounded or neutral conductor. |
What dimensions are used to measure the area of a dwelling to determine the lighting load? | The floor area for each floor shall be calculated from the outside dimensions of the building, dwelling unit; NEC Section 220.12.\n - [NEC Section ](): "" | The floor area for each floor shall be calculated from the outside dimensions of the building, dwelling unit; NEC Section 220.12. |
What is the smallest copper wire size allowed for service-entrance conductors supplying limited loads of a single branch circuit? | For limited loads of a single branch circuit, No. 12 copper may be used, but in no case smaller than the branch-circuit conductors. NEC Section 230.31_(B), Exception.\n - [NEC Section 230.31_(B)](https://2023.antflix.net#230.31_(B)): "The conductors shall not be smaller than 8 AWG copper or 6 AWG aluminum or copper-cla... | For limited loads of a single branch circuit, No. 12 copper may be used, but in no case smaller than the branch-circuit conductors. NEC Section 230.31_(B), Exception. |
What is the allowable number of service disconnects according to NEC regulations? | The service disconnection means shall consist of not more than six switches or six circuit breakers: NEC Section 230.71_(A)\n - [NEC Section 230.71_(A)](https://2023.antflix.net#230.71_(A)): "For the purpose of this section, disconnecting means installed as part of listed equipment and used solely for the following sha... | The service disconnection means shall consist of not more than six switches or six circuit breakers: NEC Section 230.71_(A) |
How much clearance must service conductors passing over a flat roof have from the highest point of the roof? | NEC Section 230.24_(A). See Figure 4-5 on the next page. If less than 4 inches in 12 inches, the minimum clearance of service conductors is:\n - [NEC Section 230.24_(A)](https://2023.antflix.net#230.24_(A)): "Conductors shall have a vertical clearance of not less than 2.6 m (8 ft 6 in.) above the roof surface. The vert... | NEC Section 230.24_(A). See Figure 4-5 on the next page. If less than 4 inches in 12 inches, the minimum clearance of service conductors is: |
What is the clearance required for service conductors passing over a flat roof where the voltage between conductors does not exceed 300? | NEC Section 230.24(4), Exception No.2. See Figure 4-5 on the next page.\n - [NEC Section 230.24](https://2023.antflix.net#230.24): "Overhead service conductors shall not be readily accessible and shall comply with 230.24(A) through (E) for services not over 1000 volts, nominal." | NEC Section 230.24(4), Exception No.2. See Figure 4-5 on the next page. |
When service conductors pass over not more than 4 feet of the overhang portion of the roof and terminate in a through-the-roof raceway or other approved support, what is the reduced clearance required above the roof? | NEC Section 230.24(4), Exception No. 3. See Figure 4-5 on the next page.\n - [NEC Section 230.24](https://2023.antflix.net#230.24): "Overhead service conductors shall not be readily accessible and shall comply with 230.24(A) through (E) for services not over 1000 volts, nominal." | NEC Section 230.24(4), Exception No. 3. See Figure 4-5 on the next page. |
What is the purpose of the Electrician's Exam Preparation Guide? | To help individuals prepare for the electrician's exam.\n - [NEC Section ](): "" | To help individuals prepare for the electrician's exam. |
What is the minimum clearance required for overhead service conductors, not in excess of 150 volts to ground, passing over any platform or projection that can be reached? | Overhead service conductors, when not in excess of 150 volts to ground, that pass over which the conductors may be reached, must have a minimum clearance of 10 feet. NEC Section 230.24_(B)(1). See Figure 4-5.\n - [NEC Section 230.24_(B)](https://2023.antflix.net#230.24_(B)): "Overhead service conductors, where not in e... | Overhead service conductors, when not in excess of 150 volts to ground, that pass over which the conductors may be reached, must have a minimum clearance of 10 feet. NEC Section 230.24_(B)(1). See Figure 4-5. |
What is the minimum clearance required for overhead service conductors, not in excess of 300 volts, passing over residential driveways and commercial areas not subject to truck traffic? | Overhead service conductors, when not in excess of 300 volts, that pass over residential driveways and commercial areas such as parking lots and drive-in establishments not subject to truck traffic must have a clearance of at least 10 feet. NEC Section 230.24_(B)(2). See Figure 4-5.\n - [NEC Section 230.24_(B)](https:/... | Overhead service conductors, when not in excess of 300 volts, that pass over residential driveways and commercial areas such as parking lots and drive-in establishments not subject to truck traffic must have a clearance of at least 10 feet. NEC Section 230.24_(B)(2). See Figure 4-5. |
What is the minimum clearance required for overhead service conductors, not in excess of 600 volts, passing over public streets, alleys, roads, parking lots, agricultural, or other areas subject to truck traffic? | Overhead service conductors, when not in excess of 600 volts, that pass over public streets, alleys, roads, parking lots, agricultural, or other areas subject to truck traffic must have a minimum clearance of 18 feet. NEC Section 230.24_(B)(4). See Figure 4-5.\n - [NEC Section 230.24_(B)](https://2023.antflix.net#230.2... | Overhead service conductors, when not in excess of 600 volts, that pass over public streets, alleys, roads, parking lots, agricultural, or other areas subject to truck traffic must have a minimum clearance of 18 feet. NEC Section 230.24_(B)(4). See Figure 4-5. |
What is the minimum clearance required for overhead service conductors passing over residential property, driveways, and certain commercial areas not subject to truck traffic? | Overhead service conductors, when not in excess of 600 volts, that pass over residential property, driveways, and those commercial areas not subject to truck traffic must have a minimum clearance of 15 feet. NEC Section 230.24_(B). See Figure 4-5.\n - [NEC Section 230.24_(B)](https://2023.antflix.net#230.24_(B)): "Over... | Overhead service conductors, when not in excess of 600 volts, that pass over residential property, driveways, and those commercial areas not subject to truck traffic must have a minimum clearance of 15 feet. NEC Section 230.24_(B). See Figure 4-5. |
How should multiconductor cables used for overhead service conductors be attached to buildings or other structures? | Multiconductor cables used for overhead service conductors must be attached to buildings or other structures using fittings approved for the purpose. An approved fitting, such as an insulator, is required for all such installations. NEC Section 230.27.\n - [NEC Section 230.27](https://2023.antflix.net#230.27): "Multico... | Multiconductor cables used for overhead service conductors must be attached to buildings or other structures using fittings approved for the purpose. An approved fitting, such as an insulator, is required for all such installations. NEC Section 230.27. |
Under what conditions are power distribution blocks permitted in a junction box? | Power distribution blocks are permitted in a junction box when the box is larger than 100 cubic inches. NEC Article 314.28_(E) states that 100 cubic inches is the minimum size box in which power distribution blocks may be installed. An Exception allows for grounding terminal bars in smaller boxes.\n - [NEC Section ]():... | Power distribution blocks are permitted in a junction box when the box is larger than 100 cubic inches. NEC Article 314.28_(E) states that 100 cubic inches is the minimum size box in which power distribution blocks may be installed. An Exception allows for grounding terminal bars in smaller boxes. |
How far from the service head must service-entrance cable be supported? | Service-entrance cable must be supported within 12 inches of the service head. An SE cable strap, or other approved fitting, must be installed within 12 inches of the service head. NEC Section 230.51_(A).\n - [NEC Section 230.51_(A)](https://2023.antflix.net#230.51_(A)): "Service-entrance cables shall be supported by s... | Service-entrance cable must be supported within 12 inches of the service head. An SE cable strap, or other approved fitting, must be installed within 12 inches of the service head. NEC Section 230.51_(A). |
How often must Type SE cable be supported according to NEC Section 230.51(4)? | Type SE cable must be supported at least every 2 1/2 feet (30 inches) to prevent sag or collapse.\n - [NEC Section ](): "" | Type SE cable must be supported at least every 2 1/2 feet (30 inches) to prevent sag or collapse. |
What clearance must service conductors have from windows, doors, porches, fire escapes, or similar locations? | Service conductors must have a clearance of not less than 3 feet from windows, doors, porches, fire escapes, or similar locations. However, conductors run above the top level of a window are permitted to be less than 3 feet. This is according to NEC Section 230.9_(A).\n - [NEC Section 230.9_(A)](https://2023.antflix.ne... | Service conductors must have a clearance of not less than 3 feet from windows, doors, porches, fire escapes, or similar locations. However, conductors run above the top level of a window are permitted to be less than 3 feet. This is according to NEC Section 230.9_(A). |
When installing a service head, how must the conductors of different potential be brought out? | Service heads must have conductors of opposite potential brought out through separately bushed openings. This requirement is specified in NEC Section 230.54_(E).\n - [NEC Section 230.54_(E)](https://2023.antflix.net#230.54_(E)): "Service heads shall have conductors of different potential brought out through separately ... | Service heads must have conductors of opposite potential brought out through separately bushed openings. This requirement is specified in NEC Section 230.54_(E). |
What must metal enclosures for service conductors and equipment do? | panelboards, safety switches, etc. must be grounded with the system's equipment ground. NEC Section 250.80. All metal enclosures or housings for service conductors; such as meter bases, auxiliary gutters\n - [NEC Section 250.80](https://2023.antflix.net#250.80): "Metal enclosures and raceways for service conductors and... | panelboards, safety switches, etc. must be grounded with the system's equipment ground. NEC Section 250.80. All metal enclosures or housings for service conductors; such as meter bases, auxiliary gutters |
What size service is required for a 120/240-volt; single-phase load with a demand load of 36 kVA? | Divide the voltage between phases into the total volt-amperes or watts. Thus, 36,000/240 = 150 amperes\n - [NEC Section ](): "" | Divide the voltage between phases into the total volt-amperes or watts. Thus, 36,000/240 = 150 amperes |
What size copper THW conductors are required for the service load in Question 4-32? | NEC Table 310.15_(B)(16) shows that 1/O THW wire has a current-carrying capacity of 150 amperes when the ambient temperature is 75°C or below\n - [NEC Section ](): "" | NEC Table 310.15_(B)(16) shows that 1/O THW wire has a current-carrying capacity of 150 amperes when the ambient temperature is 75°C or below |
What size rigid steel conduit is required to contain the three conductors in Question 4-32? | Table C.8 in NEC Annex C shows that 1/2 inch conduit can contain three No. 1/O THW conductors without exceeding the 40% fill requirements\n - [NEC Section ](): "" | Table C.8 in NEC Annex C shows that 1/2 inch conduit can contain three No. 1/O THW conductors without exceeding the 40% fill requirements |
What percentage of fill is allowed in a conduit with three conductors? | When three or more conductors with any type insulation, other than lead-covered, are installed in a raceway, the conductors may not exceed 40% of the raceway's cross-sectional area. NEC Chapter 9, Table 1.\n - [NEC Section ](): "" | When three or more conductors with any type insulation, other than lead-covered, are installed in a raceway, the conductors may not exceed 40% of the raceway's cross-sectional area. NEC Chapter 9, Table 1. |
If THHN copper conductors are used for the service-entrance, what size is required? | Due to the insulation on THHN conductors, they are able to stand a higher temperature and therefore have a greater current-carrying capacity. NEC Table 310.15_(B)(16) or Table 310.15_(B)(7), when applicable.\n - [NEC Section ](): "" | Due to the insulation on THHN conductors, they are able to stand a higher temperature and therefore have a greater current-carrying capacity. NEC Table 310.15_(B)(16) or Table 310.15_(B)(7), when applicable. |
What size electrical metallic tubing (EMT) is required to contain the service conductors? | 14/4 inch EMT is sufficient to handle three No. THHN conductors without exceeding the required 40% fill. NEC Table 4, Annex C.\n - [NEC Section ](): "" | 14/4 inch EMT is sufficient to handle three No. THHN conductors without exceeding the required 40% fill. NEC Table 4, Annex C. |
When using 2 1/2-inch rigid steel conduit for a through-the-roof 120/240 volt service mast, what is the minimum distance the conduit can protrude above the roof? | NEC Section 230.24_(A) Exception No.3 allows a reduction in clearance above only the overhanging portion of the roof to not less than 18 inches.\n - [NEC Section 230.24_(A)](https://2023.antflix.net#230.24_(A)): "Conductors shall have a vertical clearance of not less than 2.6 m (8 ft 6 in.) above the roof surface. The ... | NEC Section 230.24_(A) Exception No.3 allows a reduction in clearance above only the overhanging portion of the roof to not less than 18 inches. |
What is the minimum size copper grounding electrode conductor allowed on an electric service? | NEC Table 250.66 specifies a No. 4 copper or No. 2 aluminum conductor as the minimum size grounding electrode conductor.\n - [NEC Section ](): "" | NEC Table 250.66 specifies a No. 4 copper or No. 2 aluminum conductor as the minimum size grounding electrode conductor. |
Where should the main service disconnecting means be located? | The service disconnecting means must be installed at a readily accessible location either outside of a building or structure, or inside nearest the point of entrance of the service conductors NEC Section 230.70_(A)(1).\n - [NEC Section 230.70_(A)](https://2023.antflix.net#230.70_(A)): "The service disconnecting means s... | The service disconnecting means must be installed at a readily accessible location either outside of a building or structure, or inside nearest the point of entrance of the service conductors NEC Section 230.70_(A)(1). |
What does the NEC require for circuits over 150 volts to ground containing fuses? | Disconnecting means must be provided on the supply side of all fuses in circuits of over 150 volts to ground. NEC Section 240.40.\n - [NEC Section 240.40](https://2023.antflix.net#240.40): "Cartridge fuses in circuits of any voltage, and all fuses in circuits over 150 volts to ground, shall be provided with a disconnec... | Disconnecting means must be provided on the supply side of all fuses in circuits of over 150 volts to ground. NEC Section 240.40. |
How is the general lighting load for residential services calculated? | NEC Table 220.12 shows that the general lighting load for dwelling units is calculated at 3 volt-amperes per square foot.\n - [NEC Section ](): "" | NEC Table 220.12 shows that the general lighting load for dwelling units is calculated at 3 volt-amperes per square foot. |
How are residential small appliance circuits calculated? | In addition to the number of branch circuits determined by the square-foot method (based on 3 volt-amperes per square foot), two or more 20-ampere small appliance branch circuits must be provided for all receptacle outlets in the kitchen, pantry, breakfast room, dining room, or similar area of a dwelling unit. NEC Sect... | In addition to the number of branch circuits determined by the square-foot method (based on 3 volt-amperes per square foot), two or more 20-ampere small appliance branch circuits must be provided for all receptacle outlets in the kitchen, pantry, breakfast room, dining room, or similar area of a dwelling unit. NEC Sect... |
What is required for all metal enclosures for service conductors and equipment? | NEC Section 250.80 states that metal enclosures for service conductors and equipment must be grounded.\n - [NEC Section 250.80](https://2023.antflix.net#250.80): "Metal enclosures and raceways for service conductors and equipment shall be connected to the grounded conductor if the electrical system is grounded or to th... | NEC Section 250.80 states that metal enclosures for service conductors and equipment must be grounded. |
What is the minimum amperage rating for mobile home service equipment? | Mobile home service equipment shall be rated at not less than 100 amperes, and provision must be made for connecting the mobile home feeder assembly by a permanent wiring method. NEC Section 550.32_(C).\n - [NEC Section 550.32_(C)](https://2023.antflix.net#550.32_(C)): "Mobile home service equipment shall be rated at n... | Mobile home service equipment shall be rated at not less than 100 amperes, and provision must be made for connecting the mobile home feeder assembly by a permanent wiring method. NEC Section 550.32_(C). |
What is the ampacity of the conductors required for a 120/208-volt; three-phase, 4-wire commercial service with a load of 72 kVA? | 200 amperes\n - [NEC Section ](): "" | 200 amperes |
What size aluminum THW conductors are required for the service in Question 4-46? | NEC Table 310.16 shows that 250 kcmil THW aluminum conductors are rated at 205 amperes.\n - [NEC Section ](): "" | NEC Table 310.16 shows that 250 kcmil THW aluminum conductors are rated at 205 amperes. |
What size rigid steel conduit is required for the service conductors in Question 4-47? | NEC Table 6.8 in Annex C specifies a 2 1/2-inch conduit for four 250 kcmil THW conductors.\n - [NEC Section ](): "" | NEC Table 6.8 in Annex C specifies a 2 1/2-inch conduit for four 250 kcmil THW conductors. |
What is the maximum distance between supports for the conduit in Question 4-48 if the conduit is a straight run? | NEC Table 344.30_(B)(2) specifies a maximum distance of 16 feet between 2 1/2 inch rigid conduit supports.\n - [NEC Section ](): "" | NEC Table 344.30_(B)(2) specifies a maximum distance of 16 feet between 2 1/2 inch rigid conduit supports. |
What is the maximum distance for a required support for rigid steel conduit from the service head? | NEC Section 344.30(4) states that rigid metal conduit shall be firmly fastened within 3 feet of each outlet box, junction box, cabinet, or fitting. Since a service head is classified as a fitting, the maximum distance is 3 feet.\n - [NEC Section 344.30](https://2023.antflix.net#344.30): "RMC shall be installed as a com... | NEC Section 344.30(4) states that rigid metal conduit shall be firmly fastened within 3 feet of each outlet box, junction box, cabinet, or fitting. Since a service head is classified as a fitting, the maximum distance is 3 feet. |
What is the required ampacity of conductors serving a 120/240-volt single-phase residential electric service with a total load of 30 kVA? | 30,000/240 = 125 amperes\n - [NEC Section ](): "" | 30,000/240 = 125 amperes |
What size aluminum SE cable is required for the service in Question 4-51? | NEC Table 310.15_(B)(7).\n - [NEC Section ](): "" | NEC Table 310.15_(B)(7). |
What is the maximum distance that an SE cable strap can be from either the service head or the meter base? | Cable shall be secured in place at intervals not exceeding 12 inches from every cabinet, box, or fitting; NEC Section 230.51_(A).\n - [NEC Section 230.51_(A)](https://2023.antflix.net#230.51_(A)): "Service-entrance cables shall be supported by straps or other approved means within 300 mm (12 in.) of every service head,... | Cable shall be secured in place at intervals not exceeding 12 inches from every cabinet, box, or fitting; NEC Section 230.51_(A). |
What is the maximum distance allowed between cable straps when installing Type SE cable when used as service-entrance conductors? | Cable shall be secured in place at intervals not exceeding 30 inches (2 1/2 feet); NEC Section 230.51_(A).\n - [NEC Section 230.51_(A)](https://2023.antflix.net#230.51_(A)): "Service-entrance cables shall be supported by straps or other approved means within 300 mm (12 in.) of every service head, gooseneck, or connecti... | Cable shall be secured in place at intervals not exceeding 30 inches (2 1/2 feet); NEC Section 230.51_(A). |
When a single-family dwelling has an initial load of 10 kVA or above, what is the minimum service rating? | For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes; NEC Section 230.79_(C).\n - [NEC Section 230.79_(C)](https://2023.antflix.net#230.79_(C)): "For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes, 3-wire." | For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes; NEC Section 230.79_(C). |
What is the phase-to-phase voltage in a three-phase, 4-wire Y-connected service if the phase-to-neutral voltage is 240 volts? | Phase-to-phase voltage = phase-to-neutral voltage x √3 = 240 x 1.73 = 415 volts\n - [NEC Section ](): "" | Phase-to-phase voltage = phase-to-neutral voltage x √3 = 240 x 1.73 = 415 volts |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.