This is a calculation and code question.
I am working on designing a 400A 3 phase service upgrade for a large residence. I have determined that it will require 60 circuits total. Section 408.15 states that there can be no more that 42 overcurrent devices in one panel. Therefore I need to use a feed-through lug panel. I will be using a 42ckt (1st) and a 30ckt (2nd) panel
My question is this, do I need to match the amerage rating of the 1st panel with the 2nd panel? Or can I size the 2nd panel for the calculated load on that panel (70A)? Because it seems that Sq.D only makes 225A & 600A feed-through panels. I would like to minimize the cost to my client.
Thank you in advance for your assistance.
Keith
I am working on designing a 400A 3 phase service upgrade for a large residence. I have determined that it will require 60 circuits total. Section 408.15 states that there can be no more that 42 overcurrent devices in one panel. Therefore I need to use a feed-through lug panel. I will be using a 42ckt (1st) and a 30ckt (2nd) panel
My question is this, do I need to match the amerage rating of the 1st panel with the 2nd panel? Or can I size the 2nd panel for the calculated load on that panel (70A)? Because it seems that Sq.D only makes 225A & 600A feed-through panels. I would like to minimize the cost to my client.
Thank you in advance for your assistance.
Keith