woodworkingsparky
Member
Hello, I am designing a 20 unit apartment building and have run into some confusion while computing the service size(120/208v, three phase).
I have figured 20 , 12kw ranges at 29,000 va per table 220.19. In the example this load is divided by two in order to figure a per phase demand. The per phase demand is then multiplied by three to arrive at an equivalent three phase load. Why is this done? Is not a load a load when we are talking in VA?
In the above example, I computed my equivalent three phase load to be 43,500 va. If a load is truly a load why is this step needed.
Where I'm going with this is that I also have roughly 53,000 va of air conditioning load - single phase. Do I also need to convert this to an equivalent three phase load, if so, why?
Thank you in advance for your time.
I have figured 20 , 12kw ranges at 29,000 va per table 220.19. In the example this load is divided by two in order to figure a per phase demand. The per phase demand is then multiplied by three to arrive at an equivalent three phase load. Why is this done? Is not a load a load when we are talking in VA?
In the above example, I computed my equivalent three phase load to be 43,500 va. If a load is truly a load why is this step needed.
Where I'm going with this is that I also have roughly 53,000 va of air conditioning load - single phase. Do I also need to convert this to an equivalent three phase load, if so, why?
Thank you in advance for your time.