Three-phase five-wire system: it includes three-phase wires (A, B and C wires), neutral wire (N wire) and ground wire (PE wire) of alternating current.
Tn-s standard conductor colors are: A line yellow, B line blue (green), C line red, N line brown, PE line yellow-green or black.
Generally speaking, red is the fire line and blue is the zero line, both of which are fire lines. If a two-phase power supply is connected to an electrical appliance, current will flow through the wire.
Extended data 1. Color discrimination: phase A is yellow, phase B is green, phase C is red, neutral line N is light blue, and protective ground PE is yellow-green. The black line in the cable is the protective grounding PE line.
Second, from the aspect of spatial arrangement: we are facing the front of the power distribution panel. The vertically arranged view is A, B and C from left to right, the horizontally arranged view is A, B and C from inside to outside, and the vertically arranged view is A, B and C from top to bottom.
Third, distinguish from the electrical letters: ABC, corresponding to the following words: L 1, L2, L3, U, V, W and R, S, T.
Through the above method, ABC of three-phase wires can be quickly distinguished, thus correctly judging the phase sequence of three-phase electricity and accurately connecting wires.