The main goal of this thesis was to create a calculation tool for measurement of wires and electronic protection tools and likewise for client’s electricians. Also the goal was to demonstrate the impact of varying installation circumstances to the measurement.

In the theoretical part of this thesis the standards of electrical installations, various of installation methods for cables and their impact for measurements and calculations was studied. Algebraic equations were mostly based for modern standards and the way to implement them in practice.

Calculation tool was implemented with Excel spreadsheet. The basis for implementation of this tool was to use the standards for electrical installations and regulations.

The end results, was a complete software for this task, which can be scaled up later by adding new functions and algebraic equations.