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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.
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.
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
- 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.
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.
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.