Feeder Ampacity used for Voltage Drop Calc

[indmik]

What ampacity should I use to calculate voltage drop on a residential dwelling unit in an apartment building. Is it the service feeder ampacity calculated based on NEC 220?
Thanks have a great day!

Concepts in Electricity by Mike Holt grad 1984

 

[augie47]

I normally see it based on an Art 220 calculated load for that unit unless someone want to cover "future" situations.

 

[indmik]

Thanks, thought so.