Size a single circuit from load current, run length and permissible voltage drop. Regional derating: United Kingdom @ 30°C default ambient.

    Circuit Inputs

    regional default (30 °C)

    Result

    Base ampacity
    63 A
    Derated ampacity
    63 A
    Voltage drop
    4.72 V (1.18%)
    Cable OD
    22.9 mm
    Temp factor
    1.00
    Grouping factor
    1.00
    Conductor factor
    1.00
    Solar factor
    1.00
    Ambient
    30 °C

    Assumptions and scope

    Region
    United Kingdom (user-entered)
    Nominal voltage
    400 V (three-phase) (regional default)
    Ambient temperature
    30 °C (regional default) (regional default)
    Grouped circuits
    1 (user-entered)
    Solar exposure
    None (simplified model)
    Conductor
    Copper (user-entered)
    Insulation
    XLPE (user-entered)
    Voltage-drop limit
    3 % (user-entered)
    Status
    Planning estimate — requires independent engineering verification (simplified model)
    Not assessed by this planning estimator
    • Installation method is not modelled by the current simplified dataset
    • Protective-device coordination is not assessed by this planning estimator
    • Short-circuit/adiabatic withstand is not assessed

    Standard and table names shown in this tool are repository-labelled educational references for a simplified planning model. They have not been independently verified and no claim of alignment or compliance with any regional standard is made.