Electrical Calculations Software

Accurate voltage drop calculations

Provides the accurate equations

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Accurately calculating voltage drop results in lower voltage drops which leads to smaller cable sizes and saves money.

To accurately calculate voltage drop in cables utilise:

          Conductor resistance (Rc) values based on actual cable operating temperature (percent loading).

          Conductor reactance (Xc) values.  Xc = 0 for d.c. installations.

          Load power factor (cosθ).

          Accurate cable route length (L).

          Actual maximum operating load current (I).


For single phase:

For Single Phase Formula

For three phase:

For Three Phase Formula

The values for Rc and Xc are provided in the Standards.  They can also be calculated.


Standard AS/NZS 3008.1.1 Electrical Installations-Selection of cables