例如截面为35平方毫米裸铜线环境温度为25℃，载流量的计算为：按升级为50平方毫米裸铝线即得50×3×1.5=225安。
For example, the ambient temperature of 35 mm2 bare copper wire is 25 ℃, and the current carrying capacity is calculated as: 50 × 3 × 1.5 = 225 a by upgrading to 50 mm2 bare aluminum wire.
对于电缆，口诀中没有介绍。一般直接埋地的高压电缆，大体上可直接采用第一句口诀中的有关倍数计算。比如35平方毫米高压铠装铝芯电缆埋地敷设的载流量为35×3=105安。95平方毫米的约为95×2.5≈238安。
For cables, the pithy formula is not covered. Generally, for the directly buried high-voltage cable, the relevant multiple in the first formula can be directly used for calculation. For example, the carrying capacity of 35 mm2 high-voltage armored aluminum core cable buried is 35 × 3 = 105 a. 95 × 2.5 ≈ 238 a for 95 mm2.
三相四线制中的零线截面，通常选为相线截面的1/2左右。当然也不得小于按机械强度要求所允许的最小截面。在单相线路中，由于零线和相线所通过的负荷电流相同，因此零线截面应与相线截面相同。
In the three-phase four wire system, the zero line section is usually about 1 / 2 of the phase line section. Of course, it shall not be less than the minimum section allowed according to the mechanical strength requirements. In single-phase line, because the load current of zero line and phase line is the same, the section of zero line should be the same as that of phase line.