Control-circuit transformers Q: Do the requirements of Article 450—Transformers and Transformer Vaults or Article 725—Class 1, Class 2 and Class 3 Remote-Control, Signaling, and Power-Limited Circuits apply to a control-circuit transformers in a 480-volt combination motor starter?
Chances are you have encountered a wiring mass—or mess—somewhere along the road when installing voice/data/video or information transport systems. Year after year of adding, changing and rewiring may have left the plenum with little room for additional wiring and cabling.
314.28 Pull and Junction Boxes Requirements pertaining to the installation and use of all boxes and conduit bodies used as outlet, device, junction or pull boxes are in Article 314 of the National Electrical Code.
Many electrical contractors, electricians and electrical inspectors have struggled with the requirements in the National Electrical Code (NEC) for placement of lights, receptacles and switches in bathtub and shower areas. Can receptacles be installed within proximity of the bathtub or shower edge?
314.28 Pull and Junction Boxes The National Electrical Code (NEC) has specific requirements detailing how to calculate the maximum numbers of conductors in boxes (outlet, device, junction, pull, etc.) and conduit bodies.
A utility-interactive photovoltaic (PV) system is defined in Section 690.2 of the National Electrical Code (NEC) (NFPA 70-2005) as a “photovoltaic system that operates in parallel with and may deliver power to an electrical production and distribution network.” NEC Article 690 covers Solar Photovol
A new definition covering supplementary overcurrent-protective devices has been added to Article 100 in the 2005 National Electrical Code (NEC) to indicate that limited protection may be provided for specific applications or utilization equipment.
Laundry GFCI receptacles Q: Are all 15- and 20-ampere, 125V receptacles installed within six feet of a laundry or utility sink in a dwelling occupancy required to be protected by a ground fault circuit interrupter even where the receptacle is not readily accessible such as behind a clothes washer o
With the acceptance of the 2005 National Electrical Code (NEC), installing and servicing fluorescent luminaires (fixtures) has become a complex situation. The design and layout of the lighting system is critical in determining certain required added features.
314.16 Number of Conductors in Outlet, Device, and Junction Boxes, and Conduit Bodies The scope of Article 314 is covered in 314.1 and covers requirements pertaining to the installation and use of all boxes and conduit bodies used as outlet, device, junction or pull boxes, depending on their use, a
Grounding-electrode continuity Q: Does the grounding-electrode conductor to driven ground rods have to be unbroken to both rods or may a splice be made at the first rod, then continue to the second ground rod by installing two ground clamps at the first ground rod, then continuing to the second rod
For approximately 40 years, unprotected or improperly protected penetrations have presented a subject of much concern to the fire-protection community. In 1996, an electrical fire occurred at 30 Rockefeller Plaza in New York City.
314.16 Number of Conductors in Outlet, Device, and Junction Boxes, and Conduit Bodies The National Electrical Code contains provisions that limit the numbers and sizes of conductors that can be installed in boxes and conduit bodies.
Flexible cord terminations Q: May a properly sized flexible cord with 15-ampere male attachment plugs on both ends be used to supply an optional standby generator for a small business? The cord is intended to plug into a receptacle on the generator and a receptacle on the outside of the building.