Voltage Drop Calculations

[bWgibb]

Describe the solution you'd like
A function that calculates the voltage drop of a cable. I believe the inputs required would be 1ph or 3ph, conduit/buried/tray/free air, etc.), voltage, amperage at end of run, spacing between conductors. This function would be ideal the same as Southwire's online calculator (linked below).

Describe alternatives you've considered
None

Link to Formulas and Example References
https://www.southwire.com/ca/en-ca/calculator-vdrop

Additional Context

• There would have to be a standardization on cable data (e.g. impedance data).
• The function may require an input of what code book to follow if the code has specific rules for how to calculate voltage drop.

[engineerjoe440]

Hi there, @bWgibb! Thanks for this suggestion! It seems like that's some kind of proprietary calculator, or one that doesn't have direct documentation available. Do you know if there's any documentation on the formula(s) used on that page that we could use to apply as a function in ElectricPy?

I did a little digging through the Javascript on that page to see just how it's built up, and it seems like there's a call to some server to do the actual calculation, which means there's not really a way to determine the calculation directly from that page.

Do you have any other insight, or thoughts that I might've missed?

Thanks, again!!!!

[bWgibb]

A couple of options... we could ask Southwire to open-source it as part of their contribution to the technical community. This may be a long shot.

I would recommend the starting place for the voltage drop formulas being either NEC or IEEE 525. We could develop functions for voltage drop based on source (e.g. one as per NEC, one as per IEEE 525, etc.). Ideally we stick to the physics and first principles, however.

[engineerjoe440]

Thank you, @bWgibb! That would be terrific! Would you be willing to reach out to Southwire, and/or to pull resources for NEC/IEEE-525? I'd be very happy to author some functions and tests with some resources!

Thank you!