Voltage Drop

    Phase
    Conductor
    V
    A
    m
    mm²
    cos φ

    Voltage Drop Limits by Standard

    StandardLightingPowerTotal Max
    IEC 603643%5%5%
    NEC (US)3%3%5%
    BS 7671 (UK)3%5%5%
    DEWA (UAE)2.5%4%5%

    Voltage drop sizing is one half of the LV/MV design — pair it with the matching transformer class and cable specification.