In the UK the old flexible cable used Red as Positive, Black as Neutral and Green as Earth
All depends on what country you are in, wiring standards and cable type. Industrial cable in the UK is. :- Red = Live Black = Neutral Copper wire = earth. (add Green/Yellow striped sleeve at junctions.) Domestic is:- Brown = Live Blue = neutral Green/yellow stripe = Earth Europe Black = Live Blue = Neutral Brown = Earth
Red - active, (commonly known as your live cable) Black - Neutral Green - Earth
In the UK, we use three pin plugs. Neutral (blue cable), Positive (brown cable), Earth (green and yellow striped cable). Positive is also known as the Live cable. The Earth cable is an important safety feature that directs electricity safely to earth should a short-circuit cause the device's metal body (a toaster, for instance) to become live and a dangerous shock is possible to any one touching the device's metal body. Before the modern standard colouring was introduced, black was the neutral, red the positive, and green the earth. This old colouring can still be found in buildings built before the change-over.
For 3 phase, L1 is red; L2 is yellow; L3 is green; Neutral is blue; Earth is yellow&green. For single phase, L is red or brown; Neutral is black or blue; Earth is yellow&green.
The old UK colouring (still found in old installations) was black = neutral, red = positive, green = earth. The new colouring is blue = neutral, brown = positive, yellow and green stripes = earth. With the new colours: on a UK 3 pin plug when facing the contact screws on the back with the cover removed: blue goes to the left contact as there is an 'L' in blue, and Brown is to the right contact as there is an 'R' in brown.
this website is useless !
red = positive black or blue is negative and green and yellow = earth In the USA, black is considered L1 (or load 1). Red is considered L2 (or load 2). White is considered neutral, and green is considered ground or earth. White can sometimes carry the L1 or load, as in a return from a switch. Normally an electrician places an identifier on the white wire to note that it is carrying load.
In a typical residential situation there is 220 to 240 volts between the two hot wires that are typically red and black and 110 to 120 volts between neutral and either black or red. The voltage between neutral and earth should be zero.
By tradition, green is the color used for the ground cable (note: NOT the Earth return or "neutral"; that's traditionally the white).
A single-phase cable will have a line and a neutral conductor and, possibly, but not necessarily, an earth (ground) conductor. A high-voltage three-phase cable will have three line conductors. A low-voltage three-phase cable is likely to have three line conductors and a neutral conductor.
when neutral short to earth