**1. The cable length is 100 m per roll, plus or minus 0.5 meters, is in line with the national standard requirements;
**2. The decoration of the common wire models: BV single strand, BVR multi-strand, BVV Shuangjiao single strand, BVVR Shuangjiao;
**3. Wire Common Specifications: 1 square /1.5 /2.5 square square / 4 sq / 6 square feet / 10 square etc.
**4. wire marked difference BV / BVR's: BV as a single strand, BVR multi shares, the same cross-sectional area of the BVR about 10% more expensive than the BV;
**5.BVR compared with BV advantages: first, to facilitate the construction of hydropower, the second, when the board is not easy to bend the line break;
**6. GB GB4706.1-1992 / in 1998 expressly provided for the wire load current value, which is the basic method of circuit transformation followed.