Dictionary of Electrical Engineering
Commonly used terms in the Electrical industry.
-
nano
-
prefix for metric unit that indicates division by one billion.
-
nanometer
-
a metric measure of distance equivalent to one billionth of a meter.
-
National Electrical Code (NEC)
-
a standard for electrical construction, published by the National Fire Protection Association (NFPA 70-1). The National Electrical Code is often adopted by local jurisdictions and used by their electrical inspectors.
-
National Electrical Manufacturers Association (NEMA)
-
an electrical trade association that establishes standards for electrical equipment. In the case of electric motors, NEMA establishes standard frame sizes, starting torque, starting current, and other quantities for a given horsepower machine.
-
National Fire Protection Association (NFPA)
-
sponsor and publisher of the National Electrical Code and other safety standards.
-
National Television System Committee (NTSC)
-
a body that recommended the standard for colored television broadcasts in the U.S. in 1953. NTSC video contains 525 lines, a field rate of 59.94 fields/second, a horizontal frequency of 15,734.264 Hz, and an interlaced color subcarrier frequency of 3.579545 MHz. The NTSC format is also in use by many countries other than the U.S.
-
natural commutation
-
commutation of current from one switching device to another in a power electronics converter at the instant the incoming voltage has a higher potential than that of the outgoing wave, without the aid of any commutation circuitry.
See commutation
-
nautical mile (nm)
-
1,852 meters. Approximately 1 minute of arc on the earth’s surface.
-
NEC
-
See National Electrical Code
-
negative sequence
-
the set of balanced but reverse sequence (acb) components used in symmetrical component analysis. Normal load currents contain no negative sequence current.