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How To Distinguish The Purpose And Function Of A Wire By The Wire Color (2)

Apr 08, 2018

How To Distinguish The Purpose And Function Of A Wire By The Wire Color (2)

II. When selecting the wire color according to the circuit

1. AC three-phase circuit

Phase A: Yellow; Phase B: Green; Phase C: Red; Neutral or Neutral: Light Blue; Safety Ground: Yellow and Green.


2. AC circuits connected with twin wires or double strands: red and black in parallel.

3. DC circuits

Positive: Brown; Negative: Blue; Grounded neutral: Light blue.

4. semiconductor circuits

The collector of the semiconductor transistor: red; base: yellow; emitter: blue.

The anode of the semiconductor diode and rectifier diode: blue; cathode: red.

SCR anode: blue; control electrode: yellow; cathode: red.

The control electrode of the triac is yellow: the main electrode is white.

5. Internal wiring of the entire device and equipment

General Recommendation: Black; Semiconductor Circuit: White;

When there is confusion: It is permissible to select colors other than the specified color (eg, orange, purple, gray, green-blue, rose-red, etc.).

6. when the specific color

On a wire, if there are two or more than two colors that can be color-coded, depending on the specific conditions of the circuit, the color is fixed according to a certain meaning that needs to be expressed in the circuit.

Attachement: World standard for three-phase wire color requirements