IEC IDMT curves

Multiple tools relating to IEC IDMT curves. Images can be exported and used in reports if desired.

Time calculator : Calculate the trip time for any IEC IDMT curve based on given I/Is and TMS multipliers.

Result comparison : Compare on-site trip test results to see whether they're within a % range of the required time.

Curve grading : Compare the grading between two relay curves (including definite time) for a given fault level.

AC Fault Waveforms

Visualise an AC fault waveform based on the rms current and XR ratio. Make and break values are also calculated, including the DC break component.

Power calculator

Accompanying tool for the article Reactive Power & Power Factor.


Losses calculator : Calculate the active and reactive losses of a transformer based on the load.

XR convertor : Calculate the X and R values for a transformer based on voltage, rating, impedance and copper losses.

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