Wiring methods (not conductors built into equipment such as motors and controllers): metal raceways, cable armor and enclosures are joined into a continuous conductor with effective continuity to boxes and cabinets, and no wiring goes in ducts carrying dust, loose stock or flammable vapors, vapor removal ducts, or shafts containing only such ducts. Temporary wiring for power and lighting may be of a lesser class than permanent wiring but otherwise follows the subpart, and is removed as soon as construction or its purpose is complete. Feeders start at a distribution center and run as multiconductor cord or cable, in raceway, or as open conductors on insulators no more than 10 feet apart where safe from damage. Branch circuits start at a power outlet or panelboard, have overcurrent protection at conductor ampacity, open runs are fastened at intervals not over 10 feet out of harm's way, no branch conductors lie on the floor, and open-run circuits feeding receptacles or fixed equipment carry a separate equipment grounding conductor. Receptacles are grounding type and electrically connected to the grounding conductor, each branch circuit carries a separate equipment grounding conductor unless installed in complete metal raceway, and receptacles for other uses are not placed on branch circuits feeding temporary lighting or on the same ungrounded conductor of multiwire lighting circuits. Each temporary circuit has disconnect switches or plug connectors opening all ungrounded conductors. General lighting lamps are protected from contact and breakage and metal-case sockets are grounded; lights hang by their cords only if designed for it; portable lighting in wet or conductive places such as tanks and drums runs at 12 volts or less, or 120 volts with GFCI protection; boxes are used at changes in metal-clad cable or raceway; flexible cords are protected from damage and sharp edges, and may pass through doorways and pinch points only with protection; extension cords for portable tools are three-wire and rated for hard or extra-hard service, as are cords for temporary and portable lights. Temporary wiring over 600 volts is fenced or barricaded against all but authorized qualified people. Boxes and cabinets: entering conductors protected from abrasion and unused openings closed; pull and junction boxes covered (metal covers grounded), outlet boxes with covers, faceplates or canopies in energized installations; high-voltage boxes fully enclose conductors and have secured covers marked HIGH VOLTAGE (underground covers over 100 pounds qualify as secured). Knife switches are dead when open and placed so gravity does not close them, with locks where inverted or vertical double-throw. Switchboards with exposed live parts are in permanently dry places accessible only to qualified persons; panelboards are dead front in proper enclosures unless only qualified persons have access. Enclosures in damp or wet locations keep water out, weatherproof in wet locations. General wiring conductors are insulated for the conditions and identifiable by function. Flexible cords are limited to listed uses (pendants, fixtures, portable lamps and appliances, elevator cables, cranes and hoists, stationary equipment needing frequent interchange, vibration isolation, appliances designed for removal), fitted with a plug from a receptacle for some uses, and barred from substituting for fixed wiring, running through walls, ceilings or floors, doorways or windows (except protected temporary use), being attached to or concealed behind building surfaces. Cords used must be durably marked with type, size and conductor count for types S, SO, ST, STO, SJ, SJO, SJT, SJTO; are used in continuous lengths except that hard service cord No. 12 or larger may be spliced if the splice keeps the cord's insulation, sheath and usage properties; have strain relief at connections and bushings through holes. Portable cables over 600 volts use No. 8 or larger flexible stranded conductors, shielding above 2000 volts, grounding conductors, locking connectors, strain relief, only permanent molded or vulcanized splices, and marked terminations. Remaining rules cover fixture wires, fixtures and lampholders (no normally exposed live parts, except cleat-type lampholders, receptacles and rosettes mounted 8 feet or more up; fixtures over 6 pounds or 16 inches not hung by a screw shell, portable handlamps with insulating handle and guard), receptacle configuration, appliances (disconnect and rating marking), motors (disconnects in sight, meaning visible and within 50 feet, lockable where not in sight, overload and fault protection, guarding at 50 volts or more), transformers (warning of voltage, vaults for over 35 kV and hazardous oil units, no foreign pipes or storage in vaults) and capacitors (automatic discharge, interlocks or signs over 600 volts).
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.