Journeyman Electrician - Test 2 - 2014 NEC

The objective of Section 210.52(E)(1) is to provide readily accessible receptacles at the front and back of dwellings at a height of not more than 6 feet above grade level so that the receptacles are capable of being reached by the average person without the use of ladders

The B phase shall be that phase having the higher voltage to ground on 3-phase, 4-wire, delta-connected systems of industrial control panels. This rule applies to new installations. Other busbar arrangements are permitted for additions to existing installations and the phases are to be permanently marked and identified. Refer to Section 409.102(B).

The purpose of this rule, Section 225.18(4), is to maintain a safe clearance distance from ground to the overhead conductors to allow the passage of vehicle traffic in public areas. This rule helps to protect the conductors from physical damage and to protect persons and vehicles from accidental contact with the conductors.

Single locking and grounding receptacles, rated not less than 30-amperes, are required for providing shore power to boats. The intent of Section 555.19(A)(4) is to ensure proper connections and prevent unintentional disconnection of on-board equipment such as refrigerators and bilge pumps.

As per Section 550.32(F), an outdoor mobile home disconnecting means shall be installed so the bottom of the disconnecting means enclosure is not less than 2 ft. above finished grade or working platform. The 2 ft. clearance required above finished grade should help to prevent water from entering the enclosure.

To determine the allowable ampacity of the 3-conductor size 6 AWG XHHW aluminum SER cable, refer to Table 310.104(A) and note the cable is rated for when used in a dry location. Next, find the ampacity of the conductors before derating, which is 55 amperes, from Table 310.15(B)(16). Finally, due to the elevated temperature, apply the temperature correction factor found on Table 310.15(B)(2)(a). Do the math as shown:

Size 6 AWG AL XHHW ampacity before derating = 55 amperes
55 amperes x .87 (temperature correction) = 47.85 amperes

The intent of Section 501.15(C)(6) is to minimize the passage of gases from one portion of the electrical system to another and to ensure an adequate area is available for pouring the sealing compound. As per Table 1, Chapter 9, the maximum permitted fill area for conduit is 40%; the maximum fill area permitted for standard conduit seals is 25%. If the conduit fill exceeds 25% of the cross-sectional area of the sealing fitting, a larger trade size sealing fitting is required.

The requirement of Section 406.12(B), mandating nonlocking-type receptacles to be listed tamper-resistant in guest rooms of hotel and motels is intended to increase safety for children since the rooms are also occupied by children. Tamper-resistant receptacles are designed to prevent the insertion of metal objects such as paper clips which would create a shock hazard.

Table 300.5, Column 1, shows under this condition, the cables or conductors are to have a minimum earth cover of 18 inches. The purpose of Table 300.5 is to reduce the risk of an accident during excavation near underground installed conductors, direct-buried cables, and conduits.

Section 330.30(D)(2) permits listed MC cable fittings as a means to support the last 6 ft. of MC cable supplying a luminaire in an accessible ceiling and additional means of support is not required.

The requirements of Section 760.41(B) correlate with the requirements of NFPA 72. The branch circuit supplying fire alarm equipment shall supply no other loads and shall not be supplied through ground-fault circuit interrupters or arc-fault circuit interrupters. Also see Section 760.121(B). The intent of these two sections is to maintain the circuit in the event of an arc-fault or ground-fault so the heat and smoke detectors have the ability to activate in the event of a fire.

The intent of Section 682.11 is to prevent damage to the on land service equipment in the event of tidal waters or flooding.

Section 300.5(E) does not require underground splices of direct-buried cables or conductors to be in a box or protected by a covering of concrete when made in an approved manner in accordance with Section 110.14(B). Where underground splices are made in accordance with 110.14(B), which requires the splicing means to be listed for underground use, the sealed wire connector systems are listed for underground splicing. They restore the insulation integrity of the spliced conductors in a permanent joint.

Section 250.112(I) permits equipment supplied Class 1 circuits of less than 50 volts to not be grounded.

To solve this problem apply the single-phase current formula as follows:

I = power I = 18 kW x 1,000 = 18,000 = 75 amperes
volts 240 volts 240

The grounded conductor of an ac service is connected to a grounding electrode system to limit the voltage to ground imposed on the system by lightning and line surges. It also stabilizes the voltage to ground during normal operation, including short circuits. Refer to Section 250.24(A).

As shown in Table 310.104(A) and Table 310.15(B)(16) conductors with THHN insulation have a temperature rating of 90C.

To prevent the use of floor receptacles and extension cords, receptacles are required to be installed directly above a show window. One receptacle is required for every 12 linear ft. or "major fraction thereof" (6 ft. or more). Refer to Section 210.62. The calculation for 80 continuous feet of show window is as follows:

80 ft. (show window) = 6.7 = 7 receptacles
12 ft. (per receptacle)

The requirement of Section 690.61 is to prevent energizing of otherwise de-energized system conductors or output conductors of other off-site sources such as the utility company, and is intended to prevent electrical shock. This feature is normally provided as part of the utility-interactive inverter.

As mandated per Section 430.24(1)&(2) conductors that supply more than one continuous-duty motor on a single circuit are required to have an ampacity of not less than 125% of the full-load current of the highest rated motor in the group, plus 100% of the full-load current rating of all remaining motors in the group. First, find the full-load current values of the motors as given in Table 430.250, do the math, then, select the conductor size applying Table 310.15(B)(16).

15 hp FLC - 42 amperes x 125% = 52.5 amperes
7 hp FLC - 22 amperes x 100% = 22.0 amperes
3 hp FLC - 9.6 amperes x 100% = 9.6 amperes
Total = 84.1 amperes

*NOTE: Size 4 AWG THWN conductors with an allowable ampacity of 85 amperes should be selected.

The information given on a transformer nameplate is necessary to determine the overcurrent protection, but the overcurrent protection value is not indicated on the nameplate. Refer to Section 450.11.

As required by Section 310.10(H)(2), where connected in parallel, all conductors of the same phase are to be the same size in circular mil area and have the same insulation type. In addition to the requirement of each paralleled phase conductors being the same size and insulation type, the proper grouping of phases in relation to one another can reduce inductive heating and result in a more balanced load between each conductor of a paralleled phase.

The conductors in conduits located on or near the surface of the roof are subject to a significant increase in temperature when the roof is exposed to direct sunlight. As per Section 310.15(B)(3)(c), when this condition exists we are to apply the temperature adder values given in Table 310.15(B)(3)(c) to determine the allowable ampacity of conductors.

Where transformer vaults are not protected with an automatic fire suppression system they are to be constructed of approved materials with a 3 hour fire resistance rating. This construction method is required because of the concern for containing projectiles created in a transformer explosion and to prevent the spread of burning oil to other combustible materials. Refer to Section 450.42.

The requirement of luminaires to be installed at a height of not less than 12 ft. when located within 5 ft. horizontally of a swimming pool is to prevent a shock hazard when cleaning the pool with an extended pole. See Section 680.22(B)(1).

As per Section 690.42,IN, locating the grounding connection point as close as practicable to the photovoltaic source better protects the system from voltage surges due to lightning.

As indicated in Section 90.1(B), the NEC contains provisions necessary for safety. Compliance with the Code should result in an installation that is free from hazard but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use.

The reason EMT is required to be fastened in place at least every 10 ft. and within 3 ft. of each junction box, panelboard, or other conduit termination, is to ensure the tubing is secured in place. See Section 358.30(A).

As permitted by Section 430.109(C)(2), on ac motor circuits, a general-use snap switch is permitted as a disconnecting means when suitable for use only on ac and where the motor full-load current rating is not more than 80% of the ampere rating of the switch. If the switch is rated for 15 amperes, then the motor must have a full-load current rating of not more than 12 amperes.
15 amperes (switch) x 80% = 12 amperes

Section 220.14(I) requires receptacles on a single strap to be considered a load of 180 VA each. To determine how many receptacles are permitted to be connected to a circuit, first find the VA of the circuit (volts x amperes) and divide the result by 180 VA. Thus,

120 volts x 20 amperes = 2,400 VA (circuit)
2,400 VA (circuit) 180 VA (one receptacle) = 13 outlets

Section 300.5(D)(4) lists the raceways approved to protect conductors from damage when emerging from grade and subject to physical damage. Schedule 40 PVC conduit is not approved for such use.

The intent of Section 210.19(A)(1)(a) is to ensure conductors of branch circuits have the ability to supply power to loads without overheating.

Table 310.15(B)(16) shows the allowable ampacity of the conductor, before derating, is 255 amperes, which is multiplied by 0.82 [taken from the ambient temperature correction factors in Table 310.15(B)(2)(a)]. Thus the allowable ampacity is reduced to 209.1 amperes:

255 amperes x 0.82 = 209.1 amperes

Because four (4) of these conductors run in the raceway, Table 310.15(B)(3)(a) requires the allowable ampacity to be further reduced to 80%:

209.1 amperes x 0.8 = 167.28 amperes

Size 250 kcmil THWN copper ampacity before derating = 255 amperes
255 amps x .82 (temp. correction) x .8 (adjustment factor) = 167.28 amperes

Where a motor control circuit is tapped from the load side of the motor overcurrent protective device, fuse or circuit breaker, the size of the tapped conductor and the rating of the overcurrent device are based on whether the conductor stays within the motor control enclosure or leaves it. The overcurrent protective devices for motor control circuit conductors are listed in Table 430.72(B).

209.1 amperes x 0.8 = 167.28 amperes

Section 240.83(B) requires circuit breakers rated 100 amperes or less and 1000 volts or less to have the ampere rating molded, stamped, or marked into their handles or escutcheon areas. This rule aids in identifying the ampere ratings of circuit breakers.

To qualify as a grounding electrode, the size 2 AWG bare copper conductor is to be in one continuous 20 ft. length. Refer to Section 250.52(A)(4).

To solve this problem, first find the temperature adder, 40F, from Table 310.15(B)(3)(c) due to the proximity of the conduit to the rooftop exposure to sunlight then, add this value to the outdoor ambient temperature:

outdoor ambient temperature = 100 deg. F
adder (3" above roof) + 40 deg. F
TOTAL = 140 deg. F (for derating)

Table 310.15(B)(16) shows the allowable ampacity of the 8 AWG THWN copper conductors to be 50 amperes before derating, which is multiplied by 0.58 [taken from the ambient temperature correction factors in Table 310.15(B)(2)(a)]. Thus the allowable ampacity is reduced to 29 amperes:
Size 8 AWG THWN ampacity (before derating) = 50 amperes
50 amperes x .58 (temperature correction) = 29 amperes

Table 310.104(A) shows conductors with MTW insulation to be oil resistant.

As required by Section 645.15, all non-current-carrying metal parts of an information technology system shall be bonded to the equipment grounding conductor or shall be double insulated.

The requirement in Section 210.6(A)(1), limiting the voltage of luminaires to 120 volts, is intended to reduce the exposure of residents in dwellings and similar occupancies to electric shock hazards when using or servicing permanently installed luminaires and cord-and-plug connected portable lamps.

As per Section 550.32(C) mobile home service equipment shall be rated at not less than 100 amperes at 120/240 volts, single-phase.

The intent of this rule, addressed in Section 680.71, is to prevent a shock hazard in the area surrounding a hydromassage tub that may have the presence of water.

To minimize the potential for making inadvertent contact, overhead service-drop conductors are to have a clearance from final grade of not less than 10 ft., where the voltage does not exceed 150 volts to ground. Refer to Section 230.24(B)(1).

To calculate the voltage-drop on this circuit, first locate the circular mil area of the conductors (52,620 CM) as indicated in Chapter 9, Table 8. Then apply the single-phase voltage-drop formula:

VD = 2KID VD = 2 x 12.9 x 90 amps x 225 ft. = 9.92 volts dropped
CM 52,620 CM

Section 525.32 was initiated due to the transient nature of carnivals, fairs and similar events. Verification of the grounding system continuity each time equipment is reconnected helps ensure the safety of workers and personnel of the general public who may come in contact with electrical equipment.

The intent of Section 110.26(A)(2) is to provide enough accessible working space for personnel to operate and maintain the equipment in a safe manner.

The required GFCI protection as mandated in Section 511.12 applies to receptacles supplying specific types of utilization equipment used by repair technicians in commercial garages and similar occupancies where the floor surface is typically concrete slabs with direct or indirect contact with the earth. Section 210.8(B)(8) requires all 125-volt, single-phase 15- or 20-ampere receptacles in commercial garages to be provided with GFCI protection. In this environment the possibility of dampness or standing water increase the potential for electric shock.

Note 1 to Table 430.52 clarifies the use of Class CC fuses for motor branch-circuit, short-circuit, and ground-fault protection is permitted and they are to be sized at the same value as nontime-delay fuses.

Table 408.5 shows the minimum amount of wiring space required between the bottom of enclosures and busbars. This wiring space is provided to permit adequate clearance distance for the installation and termination of the conductors in the enclosure.

Section 250.102(D) permits a single equipment bonding jumper to connect two or more raceways or cables if the bonding jumper is sized in accordance with 250.122 for the largest overcurrent device protecting the conductors in the raceway. Since the largest overcurrent device protecting the conductors in this raceway is rated 300 amperes, Table 250.122 shows the load side equipment bonding must be a 4 AWG copper conductor.

Section 408.5 mandates where conduits enter a floor-standing switchboard at the bottom, the conduit or raceways, including their end fittings, shall not rise more than 3 in. above the bottom of the enclosure. The intent of this rule is to provide adequate wiring space to permit installation of the conductors in the enclosure.

As indicated in Section 324.10(E), the use of FCC systems is permitted in damp locations. But according to Section 324.12(4), the use of FCC systems is prohibited in schools, and hospital buildings, even though parts of these buildings may be office spaces.

Section 422.16(B)(1)(2) permits the length of the cord for a kitchen waste disposer to be no more than 36 in. This length should be adequate to connect the appliance without the use of potentially hazardous extension cords under the counter.

As per Section 424.20(A)(3) thermostatically controlled switching devices are allowed to serve as both controllers and disconnecting means for fixed electric space heating equipment where designed so that the circuit cannot be energized automatically after the device has been placed in the OFF position. This design feature eliminates shock hazards when servicing the equipment.

As mandated by Section 800.100(D), a bonding jumper not smaller than 6 AWG is required between the communications grounding electrode and the power grounding electrode system

Section 314.28(A)(1) applies to minimum dimensions of pull and junction boxes containing conductors 4 AWG or larger. For straight pulls, the minimum length of the box is based on eight times the largest raceway entering the box.

3 in. (largest conduit) x 8 = 24 inches

Where Type UF cable is installed as NM cable, according to Section 340.112, the conductor insulation shall be rated 90C. However, the ampacity of the cable is determined according to rules established for NM cable in Section 334.80.

The intent of Section 680.58 is to eliminate a potential shock hazard for personnel within 20 ft. of a fountain where water or dampness may be present.

The reason the emergency controls for motor-fuel dispensers to be located remote, but not more 100 ft. from the dispensing units is so that if an emergency occurs, the person operating the emergency controls is not exposed to the hazard. Refer to Section 514.11(B).

Section 312.6(B)(2) and Table 312.6(B) provide the requirements for wire-bending space where straight-in wiring or offset bends are used at the terminals.

To determine the minimum size required of the conductors to supply this motor, first find the full-load current rating of the motor, 74.8 amperes, from Table 430.250. Next, as per Section 430.22 multiply by 125%. Then, divide by the temperature correction factor, 0.75, from Table 310.15(B)(2)(a). Finally, select the conductor size, 1 AWG THWN, from Table 310.15(B)(16).

25 hp motor FLC = 74.8 amperes x 125% = 93.5 amperes
93.5 amps .75 (temperature correction) = 124.6 amperes

*NOTE: The wire size needs to be increased because of the elevated ambient temperature. Size 1 AWG THWN conductors with an allowable ampacity of 130 amperes should be selected.

The intent of Section 210.52(H) is to minimize strain or damage to cords and receptacles when performing household chores and tasks.

The purpose of Section 210.21(B)(1) is to prevent overloading the receptacle. In general, when a branch circuit supplies a single receptacle the receptacle is to have an ampere rating equal to the branch circuit rating.

In compliance with Section 220.54, the minimum load to be used for household electric clothes dryers is the larger of either 5000 VA or the nameplate rating of the dryer.

When calculating the total load for a farm service, the demand for the second largest load is 75%, because it is assumed all the loads will not be used continuously for an indefinite period of time. Refer to Table 220.103.

The objective in Section 690.31(C)(1) is most PV modules are designed for direct series connection by using factory-installed leads and connectors. To accomplish this series connection without wasting conductors in a multiconductor cable, use of a listed single-conductor Type USE-2 cable is permitted in PV source circuits.

The minimum requirements in Section 551.71 ensures the availability of the properly rated receptacles in RV parks.   Most RV sites have both 20-ampere and 30-ampere receptacles available.  Many RV sites have 20-ampere, 30-ampere and 50-ampere receptacles mounted on a common pedestal.

First find the VA of one circuit, 120 volts x 20 amperes = 2400 VA. Divide the the load, 9600 VA, by the value of one circuit, 2400 VA, as shown:

9600 VA = 4 lighting circuits
2400 VA

Section 210.17 does not demand that an outlet(s) for the specific purpose of charging electric vehicles be installed. However, when such outlets are installed (by choice) they are required to be supplied by a separate branch circuit with no other outlets because electric vehicle charging equipment is a continuous load that usually operates for several hours. If on a branch circuit with other outlets, the overcurrent protective device could trip due to overload.

Where equipment grounding conductors are installed in multiple raceways used in parallel conductor arrangements, Section 250.122(F) requires a full-sized equipment conductor selected from Table 250.122 based on the rating of the overcurrent device protecting the paralleled conductors. Therefore, the equipment grounding conductor in each raceway is capable of carrying a major portion of the fault current without burning open.

As per Section 410.154, where lighting track is installed in a continuous row, each section must be supported at least every 4 ft. to adequately support the track.

To determine the minimum conductor size to supply this motor, first locate the full-load current rating of the motor, 52 amperes, from Table 430.250. Next, as per Section 430.22 multiply this value by 125%. Then, select the conductor size, 6 AWG THWN, from Table 310.15(B)(16).

40 hp FLC = 52 amperes x 125% = 65 amperes

Essential electrical systems of health care facilities must have two independent sources of power, a normal source, usually from the utility company, and an alternate source such as a generator. Upon loss of the normal source of power, through an automatic transfer switch, the power is switched to the alternate source and the essential electrical systems will not encounter a total loss of power. Refer to Section 517.35(A).

As per Section 511.3(C)(2)(a) in an area of a major repair garage where natural gas vehicles are repaired, the area within 18 in. of the ceiling is considered unclassified where adequate ventilation is provided.

Section 220.12 requires a unit load not less than specified in Table 220.12 shall constitute the minimum lighting load.
First, find the lighting load, in VA, of the house using Table 220.12:

2600 sq. ft. x 3 VA = 7800 VA (total lighting VA of the house)

Next, calculate the VA of one circuit:

120 volts x 15 amperes = 1800 VA (one circuit)

Finally, determine the number of circuits required:

7800 VA (load) = 4.3 = 5 lighting circuits
1800 VA (one circuit)

The purpose of Section 210.52(A)(2)(1), requiring a receptacle to be located in a wall space 2 ft. or more in width, is to eliminate the need for extension cords in spaces often used for small pieces of furniture on which a lamp or an appliance may be placed.

Standard ampere ratings of fuses and fixed-trip circuit breakers are listed in Section 240.6(A).

The intent of Section 110.15 is to eliminate injury and property damage by marking the high-leg orange in color and making personnel aware there is a high-leg present. This requirement eliminates some of the hazards of accidentally connecting 120-volt equipment and outlets to the high-leg and causing injury to people and damage to equipment.

Section 424.3(B) indicates fixed electric space-heating equipment and motors are to be considered a continuous load. Therefore, as per 210.19(A)(1)(a), the branch circuit conductors supplying the heating equipment and associated motors are to have an ampacity of not less than 125% of the load.

According to Section 517.18(A), patient bed locations in general care areas of health care facilities shall be supplied by at least two branch circuits, one from the critical branch and one from the normal system. The intent of this requirement is to have uninterrupted power available at all times at the receptacles. In compliance with 517.18(B), all receptacles are to be listed "hospital grade" and
so identified. The receptacles are to be identified by a green dot on their face.

To solve this problem apply the single-phase current formula as follows:

I = power I = 10 kW x 1000 I = 10,000 = 41.6 amperes
volts 240 volts 240

This receptacle safeguarding covers all receptacles installed in rooms and patient care areas of pediatric locations in health care facilities. This can be accomplished through use of either listed tamper-resistant receptacles or listed tamper-resistant covers, which prevents children from inserting metal objects such as paper clips into the energized parts of the receptacle. Refer to Section 517.18(C).

This mandate in Section 404.8(B), applies to switches ganged together with any wiring device where the voltage between adjacent conductors exceeds 300 volts. The barriers are required between devices fed from two different phases of a 480Y/277-volt system because the voltage between the phase conductors would be 480 volts. This requirement also applies where switches or devices are on different systems and are in the same box, such as a switch on a 277-volt system provided for lighting and a receptacle on a 120-volt system.

The intent of Section 680.43(C) is to prevent personnel from operating a switch when in or on a spa or hot tub. This rule helps to prevent shock hazards.

Luminaires supported by wall outlets or ceiling outlets must be securely attached. Care should be taken to securely fasten the supporting means of the luminaire. Sections 314.27(A)(1)&(2) require boxes designed to support luminaires that weigh more than 50 lbs. must be listed and marked with the maximum weight the box can support, otherwise the luminaire shall be supported independently of the box.

As per Section 430.6(A)(2), the ampere rating provided on the motor nameplate is used to size the overload protective devices intended to protect the motor.

Section 445.13 requires where the design and operation of the generator does not prevent overloading, the ampacity of the phase conductors from the generator terminals to the first overcurrent protection device shall not be less than 115% of the nameplate current rating of the generator.

In Class II, Division 1 locations, boxes or fittings shall be provided with threaded bosses for connection to conduit or cable terminations and shall be dusttight. This requirement helps to prevent the entrance of combustible dust. Refer to Section 502.10(A)(3).

As per Section 220.82(A) the optional calculation method addressed in Section 220.82 is permitted only if the service-entrance or feeder conductors have an ampacity and calculated demand load of at least 100 amperes.

Column B of Table 220.55 shows the demand factor to be applied for one household 8 kW electric range to be 80%. Thus,
8 kW x 80% = 6.4 kW demand

Section 230.23(B) indicates the smallest size conductors permitted for overhead service-drop conductors to be 8 AWG copper or 6 AWG aluminum or copper-clad aluminum. Do not get service-drop conductors, the overhead conductors installed in free air between the utility electric supply system and the service point, confused with the service-entrance conductors; the conductors from the service point from the utility company to the service disconnecting means.

In compliance with the rules set forth by Section 422.23, requiring GFCI protection for this type of equipment will greatly reduce electrical shock hazard incidents. Tire inflation machines and automotive vacuum machines at service stations, convenience stores and car washes are often subject to damage by the public to the point of abuse and are typically exposed to the elements. This type of equipment will be typically used outdoors in rain, snow and puddles of accumulated standing water, which are contributing factors that increase the risk of an electrical shock hazard. In the past, GFCI devices have demonstrated their value in preventing electrocution in exactly these types of conditions.

Section 334.116(B) indicates the overall covering of Type NMC cable shall be flame retardant, moisture resistant, fungus resistant, and corrosion resistant.

Table 310.15(B)(16) shows the allowable ampacity of the conductors is 25 amperes, before derating, which is multiplied by 0.67 [taken from the ambient temperature correction factors in Table 310.15(B)(2)(a)]. Thus the allowable ampacity is reduced to 16.75 amperes:

25 amperes x .67 = 16.75 amperes

In compliance with Section 220.43(B), when calculating the number of branch circuits required, or the service or feeder load for track lighting, a load of 150 VA is to be included for every 2 ft. of lighting track or fraction thereof.

Table 1 of Chapter 9 shows where a conduit or tubing contains more than 2 conductors, the raceway is permitted to be filled to 40% of its cross-sectional area.

As shown, first calculate the total area occupied by the conductors, using Table 5 of Chapter 9:

Size 10 AWG THHW = .0243 sq. in. x 24 = 0.5832 sq. in.
Size 10 AWG THHN = .0211 sq. in. x 10 = 0.2110 sq. in.
Size 12 AWG THHN = .0133 sq. in. x 14 = 0.1865 sq. in.
Total = 0.9807 sq. in.

Next, use Table 4 of Chapter 9 to select the proper trade size EMT permitted to enclose the conductors. Trade size 2 in. EMT with a 40% allowable fill of 1.342 sq. in. should be selected.

In order to readily identify and trace conductors in pull boxes or junction boxes having any dimension over 6 ft., Section 314.28(B) requires all conductors to be cabled or racked up in an approved manner.

The provision at Section 330.30(D) permits interlocked armor Type MC cable to be unsupported in lengths not exceeding 3 feet from the last point of support. This would apply where flexibility is necessary to minimize the transmission of vibration from equipment such as motors.

Sections 210.8(A)(1),(2)&(3) specifically require all 125-volt, single-phase 15- and 20-ampere receptacle outlets located in garages, bathrooms and outdoors of a dwelling unit to be provided with GFCI protection. Receptacle outlets located in hallways of dwelling units are not required to be GFCI protected.