National Electrical Installation Standards

Standards as High as Your Own

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Tuesday, March 6, 2018

Question:

There are many good voltage drop calculation calculators available on the Web.  You can also do your own using the NEC and Table 9. However, do you know of a voltage drop calculator for medium voltage? Say 4,160 volts. I need to calculate the voltage drop for a 600 HP, 4,160 volt motor, 80 full load amps.

Thanks, Alton Tupa

A

Answer:

Hey Alton thanks for your question. Here are some online voltage drop calculators that seem to allow voltages above 1000 and there are probably others You should confirm with the providers that they are actually intended to be used for that purpose.

https://www.generalcable.com/eu/en/information-center/tools-applications/gc-app-medium-voltage

http://www.calculator.net/voltage-drop-calculator.html

https://www.electricaltechnology.org/2014/12/advance-voltage-drop-calculator-voltage-drop-formula.html

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