Search results
Results From The WOW.Com Content Network
The international standard IEC 60446 Basic and safety principles for man-machine interface, marking and identification - Identification of equipment terminals, conductor terminations and conductors was a standard published by the International Electrotechnical Commission (IEC) that defined basic safety principles for identifying electrical conductors by colours or numerals, for example in ...
The UK changed colour codes three decades after most other European countries, as in 1977 the change of neutral and phase colours was not considered safe by the IEE. Blue, previously used as a phase colour, is now the colour for neutral. Black, which was previously used for neutral, now indicates a phase.
Three-phase transformer with four-wire output for 208Y/120 volt service: one wire for neutral, others for A, B and C phases. Three-phase electric power (abbreviated 3ϕ [1]) is a common type of alternating current (AC) used in electricity generation, transmission, and distribution. [2]
The single-phase colours of red phase and black neutral are replaced by brown phase and blue neutral. These colours have been used in appliance flexible cables since 1969. The cable core colours are described in IEC 60304 (1982-01), Standard colours for insulation for low- frequency cables and wires. The three-phase phase colours are brown ...
Lighting and general purpose receptacles are at 120 volts AC, with larger devices fed by three wire single-phase circuits at 240 volts. In commercial construction, three-phase circuits are often used. Common 3 phase configurations within a building are 208v/120 wye, 120/240 center tapped delta and 480v/277v wye. Lighting is usually fed by 277 V ...
However, it is a common misconception that "hot" conductor colour-coding is required by the Code. In the United States, colour-coding of three-phase system conductors follows a de facto standard, wherein black, red, and blue are used for three-phase 120/208-volt systems, and brown, orange or violet, and yellow are used in 277/480-volt systems.
The first letter of the color code is matched by order of increasing magnitude. The electronic color codes, in order, are: 0 = Black; 1 = Brown; 2 = Red; 3 = Orange;
Since some wiring may be reversed, which would make motors turn backward, many machines on construction sites feature a phase swap plug that allows the L2 and L3 phase pins to be swapped, thereby reversing the phase sequence. Three-phase electric motors do not need the neutral wire to function, so that there is also a red four pin variant (3 ...