sceepe
Senior Member
Ok here is situation. Panel 1 is service entrance and feeds panel 2. Panel 2 feeds loads. If all conductors are sized to provide 2% Vdrop for feeders and 3% Vdrop for branch circuits (per Ashrae 90.1).
Is it permissible to have 2% drop from poco xfmr to panel 1, 2% drop from panel 1 to panel 2, and 3% dropped from panel 2 to a load? This would mean load voltage could be 7% below poco xfmr voltage. This would be worse if you had more intermediate panels. Is there any code requirement for maximum cumulative voltage drop (or minimum voltage) at the terminal load?
Is it permissible to have 2% drop from poco xfmr to panel 1, 2% drop from panel 1 to panel 2, and 3% dropped from panel 2 to a load? This would mean load voltage could be 7% below poco xfmr voltage. This would be worse if you had more intermediate panels. Is there any code requirement for maximum cumulative voltage drop (or minimum voltage) at the terminal load?