BS Cable Sizing Calculations

This section details the BS7671 standards De-rating factor, Voltage Drop, Short Circuit, Earth Fault and Cable Temperature calculations.

Reference BS standard tables used for Core Sizes and Current Rating is

BS Standard Table 4D1A to Table 4J4A

The core sizes and current ratings of cables are used in the equations to calculate the voltage drop, and cable sizes under short circuit and earth fault conditions

Note:
Flexible cables and DC cable sizes are not covered in this release.