Kansas Journeyman Electrician Exam (ICC KGH, 2017 NEC)

Key Concepts

Article 90 — Scope, arrangement, enforcement - Purpose (90.1(A)): "the practical safeguarding of persons and property from hazards arising from the use of electricity." The Code "is not intended as a design specification or an instruction manual for untrained persons." - Covered (90.2(A)): "the installation and removal of electrical conductors, equipment, and raceways; signaling and communications conductors, equipment, and raceways; and optical fiber cables and raceways" — for public and private premises (including mobile homes, RVs, floating buildings), yards/lots/parking lots/carnivals/industrial substations, connections to the supply of electricity, and utility office buildings, warehouses, garages, machine shops, and recreational buildings not integral to a generating plant, substation, or control center. - Not covered (90.2(B)): installations in "ships, watercraft other than floating buildings, railway rolling stock, aircraft, or automotive vehicles other than mobile homes and recreational vehicles"; underground mine installations and self-propelled mobile surface mining machinery; railway installations used exclusively for rolling stock or signaling/communications;…

Key Concepts

Number of services. A building or structure shall be supplied by only one service unless permitted by 230.2(A) through (D). Additional services are permitted without special permission where capacity requirements exceed 2,000 amperes at 1,000 volts or less — 230.2(C)(1). Special permission (written consent of the AHJ) covers multiple-occupancy buildings with no space accessible to all occupants and buildings large enough to require two or more services — 230.2(B). Where a building has more than one service, feeder, or branch circuit, a permanent plaque or directory must be installed at each service disconnect location — 230.2(E). Service conductors supplying one building shall not pass through another — 230.3.

2017 NEC

Key Concepts

Minimum feeder conductor size and ampacity — 215.2(A)(1) Feeder conductors must have an ampacity not less than required to supply the load calculated per Parts III, IV, and V of Article 220, and must be sized to carry not less than the larger of 215.2(A)(1)(a) or (b): - (a) Where a feeder supplies continuous loads, or any combination of continuous and noncontinuous loads, the minimum feeder conductor size shall have an allowable ampacity not less than the noncontinuous load plus 125 percent of the continuous load (Handbook pp. 90–91). - (b) Not less than the maximum load to be served after the application of any adjustment or correction factors.

Key Concepts

Overcurrent protection of conductors - Conductors must be protected in accordance with their ampacities in 310.15, unless otherwise permitted in 240.4(A) through (G) [240.4]. - Small conductor limits apply after ambient temperature and conductor-number correction factors are applied [240.4(D)]: 18 AWG Cu — 7 A, if continuous loads do not exceed 5.6 A and protection is by branch-circuit-rated CBs or fuses listed and marked for 18 AWG Cu, or Class CC, J, or T fuses [240.4(D)(1)]; 16 AWG Cu — 10 A, continuous loads not over 8 A [240.4(D)(2)]; 14 AWG Cu — 15 A [240.4(D)(3), Handbook p. 150]. - 240.4(B) permits the next higher standard OCPD rating above conductor ampacity only if all three conditions are met: (1) the conductors are not part of a branch circuit supplying more than one receptacle for cord-and-plug-connected portable loads, (2) the ampacity does not correspond to a standard fuse/CB rating, and (3) the next…

Key Concepts

General wiring requirements (Article 300) - Chapter 3 wiring methods are used for 1000 volts, nominal, or less where not specifically limited; permitted over 1000 volts where specifically permitted elsewhere — 300.2(A). - Cables/raceways laid in notches in wood members must be protected by a steel plate at least 1.6 mm (1/16 in.) thick, installed before the building finish — 300.4(A)(2). - Cable or raceway run parallel to framing members or furring strips: nearest outside surface not less than 32 mm (1-1/4 in.) from the nearest edge where nails or screws are likely to penetrate — 300.4(D). - Under metal-corrugated sheet roof decking: not less than 38 mm (1-1/2 in.) from the lowest surface of the decking to the top of the cable, raceway, or box — 300.4(E). - Vertical raceway conductor support: copper 6 AWG through 1/0 AWG — supports at intervals not greater than 100 ft — Table 300.19(A).

Key Concepts

Luminaire locations (Art. 410, Part II) - No cord-connected luminaires, chain-, cable-, or cord-suspended luminaires, lighting track, pendants, or ceiling-suspended (paddle) fans within a zone 900 mm (3 ft) horizontally and 2.5 m (8 ft) vertically from the top of the bathtub rim or shower stall threshold [410.10(D)]. Luminaires inside that footprint up to 8 ft must be marked for damp locations, or wet where subject to shower spray. - Luminaires under metal-corrugated sheet roof decking: not less than 38 mm (1½ in.) from the lowest surface of the decking to the top of the luminaire [410.10(F)]. - Combustible material must not be subjected to temperatures above 90°C (194°F) [410.11; also 410.118 for recessed]. - Lampholders over highly combustible material must be unswitched; unless an individual switch is provided for each luminaire, they must be at least 2.5 m (8 ft) above the floor or located/guarded so lamps cannot be readily removed…

2017 NEC

Key Concepts

Motor controller markings — 430.8. A controller must be marked with the manufacturer's name or identification, the voltage, the current or horsepower rating, and the short-circuit current rating. Exception No. 4: the short-circuit current rating is not required for controllers rated less than 2 hp at 300 V or less that are listed exclusively for general-purpose branch circuits.

Controller ratings for small stationary motors — 430.83(C). For stationary motors rated 2 hp or less and 300 volts or less, a general-use switch may serve as controller if its ampere rating is not less than twice (200 percent of) the motor full-load current. Alternatively, a general-use ac snap switch (ac only) may be used where the motor FLC is not more than 80 percent of the switch's ampere rating.

Key Concepts

• Table values, not nameplate. For general motor applications, the values in Table 430.247, Table 430.248, Table 430.249, and Table 430.250 shall be used to determine the ampacity of conductors or ampere ratings of switches and branch-circuit short-circuit and ground-fault protection, instead of the actual current marked on the motor nameplate — 430.6(A)(1). Exception: motors built for low speeds (less than 1200 RPM) or high torques, and multispeed motors, use nameplate current ratings.
• Branch-circuit conductors. Conductors supplying a single motor used in a continuous duty application shall have an ampacity of not less than 125 percent of the motor full-load current rating as determined by 430.6(A)(1) — 430.22 (NEC, p. 501). Motor nameplate FLA is not to be used to size branch-circuit conductors.
• Wye-start, delta-run. Line-side conductors not less than 125 percent of FLC; conductors between controller and motor not less than 72 percent of FLC (58% × 1.25) —…

Key Concepts

Location classification (Article 500) - Class I, Division 1 — ignitible gases/vapors normally present [500.5(B)(1)]. Class II — hazardous because of combustible dust [500.5(C)]. Class III — easily ignitible fibers or combustible flyings handled, manufactured, or used but not likely suspended in ignitible quantities [500.5(D); 503.1]. Class III has no material group designations (Handbook commentary, 503.1); Div 1 = manufacturing/handling, Div 2 = storage with no manufacturing. - Dusts containing magnesium or aluminum are "particularly hazardous," requiring extreme precaution — Group E [500.5(C)(1), Informational Note]. - Ammonia refrigerant machinery rooms may be unclassified where mechanical ventilation operates continuously or is initiated by detection at a concentration not exceeding 150 ppm [500.5(A)].