输入参数
可编辑的示例值估算结果
实时计算结果最小 · 面积 · 压降
3.93 mm²
面积
4 mm²
Voltage-drop criterion only
压降
1.31 %
2.62 V · 39.3 W 损耗
这些结果用于初步规划。选购设备前，请核对计算假设。
系统不会自动获取位置或电价，计算以您输入的数据为准。
如何使用这个计算器
填写电流和单程线长。结果只按电压下降计算线径，载流量、保护装置和当地安装要求还需单独核对。
计算方法
DC loop resistance = 2 × one-way length × resistivity ÷ area. Voltage drop = current × resistance. Required area = 2 × length × current × resistivity ÷ allowed voltage drop. Copper ρ20 = 0.0175 and aluminium ρ20 = 0.0282 Ω·mm²/m; temperature coefficients are 0.00393 and 0.00403 /°C.
使用结果之前
Voltage-drop sizing only: this does NOT check ampacity, insulation voltage, conduit fill, bundling, ambient derating, protective devices, connectors or local electrical rules. Final cable selection must satisfy those checks. Do not use this DC model for three-phase AC.
Is the suggested mm² safe for the current?
Not necessarily. It only meets the entered voltage-drop target. An installer must separately verify ampacity and installation requirements.