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General Installation Requirements and Branch Circuits.
Articles 90 through 210

Article 90 - Introduction: The scope of the NEC, the inspectors responsibility, and the listing of products. Article 110 General Requirements: The general installation requirements such as splices, working space, interruption rating, mechanical execution of work. Article 200 - Grounded Conductor Identification: The identification of the grounded (neutral) conductors. Article 210 - Branch Circuits: Includes circuit rating, location of receptacles, switches and lights.

Feeder Calculations, Outside Wiring, Services, Overcurrent Protection.
Articles 215 through 240

Article 215 - Feeders: Subjects include, minimum rating, size overcurrent protection and high-leg conductor identification. Article 220 - Branch and Feeder Calculations: A general discussion of branch circuits, feeders and service calculations both standard and optional calculations. Article 225 - Outside Wiring: Disconnect and circuit conductor requirements. Articles 230 - Services: Conductor sizing and protection, equipment and disconnection means. Article 240 - Overcurrent Protection: Next size up and tap rules, location of overcurrent protection devices, etc.

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Grounding and Bonding.
Article 250

Grounding is the largest, most important and one of the least understood articles in the NEC. These questions/answers should give you a working knowledge of grounding and bonding, but more importantly, they are designed to help you analyze these critical NEC requirements. Subjects include the purpose of grounding, its operations, system grounding versus circuit grounding, location of grounding connection, enclosure grounding, equipment grounding, and methods of grounding and bonding. Also covered is the grounding electrode system, grounding conductors, grounding conductor connections and how to properly ground and bond services, transformers, separate building, enclosures and appliances!

Wiring Methods - Conductors, Cables, and Raceways.
Articles 300 through 362

Article 300 - Wiring Methods: Learn the general installation requirements for wiring methods, such as conductors must be in the same raceway, requirements when run through fire openings, plenums, etc. Article 305 - Temporary Wiring: GFCI protection and other topics. Article 310 - Conductor Properties: Such as circular mils, insulation, ampacity and overcurrent protection. Articles 328 through 362 - Cables and Raceways.

Boxes, Disconnects, Panels, Cords, Fixtures and Receptacles.
Articles 370 through 410

Article 370 - Outlet and Pull Boxes: Sizing of outlet boxes, conduit bodies, and pull boxes as well as the requirements of box supports. Article 380 - Switches: Location of switches, use of circuit breakers for switching and grounding of switch plates. Article 384 - Switchboards and Panelboards: Dedicated and working space requirements, requirements for lighting and appliance branch-circuit panelboards, and the termination of the grounded and grounding conductors. Article 400 - Cords: Use of cords and common violations. Article 402 - Fixture Wires: Uses permitted and uses not permitted as well as minimum size. Article 410 - Fixtures and Receptacles: The installation requirements for fixtures and receptacles.

Appliances, Electric Heating, Motors, Air Conditioning, Transformers.
Articles 422 through 450

Article 422 - Appliances: Use of cords and the disconnecting mean requirement and Circuit rating. Article 424 - Fixed Electric Space Heating Equipment: Conductor and overcurrent protection sizing as well as disconnecting means requirement. Article 430 - Motors: Disconnecting means for motor control circuits, controller and motors. Sizing of branch circuits and feeder conductors and short-circuit and ground-fault protection devices. Article 440 - Air Conditioning: Conductor and overcurrent protection sizing as well as the requirements for disconnecting means. Article - 450 Transformers: Transformer overcurrent protection and installation requirements.

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