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Three-Phase RMS Ammeter with Current Transformers

Display on an LCD following parameters for each phase: - the RMS current - the maximum reached - the maximum of sliding average.

True RMS current measurement on 3 phases with current transformers. The results are displayed on a 20x4 Character HD44780 based LCD.

The LCD displays the following values for each mains phase:

the RMS current
the maximum RMS current reached
the maximum of RMS current sliding average
Practical assembly:
The current transformers are mounted on a veroboard plate together with the zeners for protection against disconnection. They are located at the input of the main switchboard. In the picture below you can see the mains phase wires passed through the holes of the three transformer and the cable linked to the main unit.”

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