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I am trying to simulate in LabView, an overcurrent relay of an electrical substation. 

I need to build the protection VI. Generate internally an overcurrent fault signal that can be compared to a Time-Current Characteristic Curve (IEC or IEEE), and then give a open-circuit signal. HELP!

Edited by Alvaro Espínola
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You didn't give much to go on, since I'm not familiar with IEC or IEEE Time-Current curves.  So attached is some code that allows you to set the current and the Amp Hours are then calculated and if it goes over a limit then a boolean turns on.

Overcurrent Test.vi

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  • 2 years later...

Why post a critical remark to what looks like a homework question from 2.5 years ago? Acquiring electrical current data is not the challenge of this problem which is very doable with the correct hardware. The challenge is knowing when the current exceeds the "Time-Current Characteristic Curve". The curve defines for a given current level how much time passes before an over-current occurs. The higher the current the quicker the reaction time, but the shapes can vary.  


Edited by gleichman
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