How to separate positive and negative wires

1. the positive and negative poles of the wire is first distinguished from the color of the wire: red for the positive pole, black for the negative pole, this is the national standard regulations set;

2. from the symbols of the marking to distinguish between: "+" for the positive pole, "-" for the negative pole;

3. p>3. Measured by the DC file of the multimeter: when the test is positive, the test end of the red pen is positive and the test end of the black pen is negative, and vice versa, when the test is negative, the test end of the red pen is negative and the test end of the black pen is positive.

The positive and negative poles are said to be DC circuits; AC circuits, phase line "L" and zero line "N" (also often called fire "L" line and zero line "N"), non-professionals on the two easy to confuse mistaken.