Tools

Free electrical engineering tools

Interactive apps and calculators for students and working engineers. They are all free and run in your browser.

SubstationPro

Hands-on training for protection relays: overcurrent, earth fault and directional overcurrent. Work out relay settings from real system data.

Change the inputs and see the result right away.

A visual learning platform with interactive calculators and real utility examples.

See how a transmission line’s ABCD parameters change with length and line type.

Build the Y bus and Z bus of a small network step by step.

Quick answers with the formula explained.

Work out real, reactive and apparent power, current and power factor.

Find the full load current of an AC induction motor from its rating.

Calculate how fast an overcurrent relay trips for a given fault current.

Convert current to power for single-phase and three-phase circuits.

Find voltage, current or resistance when you know the other two.

Convert per-unit line parameters into real values for your simulation.

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