Table 220.13

[jcgjupiter]

For Offices and banks for unknown receptacles
let's say 20,000 sq ft office at 3.5 va per sq ft
then 1 va per sq ft for unknown plugs. can you use table 220.13 for a demand factor for the plugs.
I know you can if you use 180 va per plug, but in my books I have seen this done both ways in the answers to questions when the 1 va per sq foot comes to over 10 kva.

In one book they show an office 15000 sq ft with unknown plugs. 15000 times 4.5 for 60000 va and thats it.

Another book takes the 15000 and applys table 220.13. Which is it?

I see that 220.13 does say In other than dwelling units receptacle loads computed at not more than 180 va per outlet. Well does that also mean any outlet computer at 1 va per square foot?

Is my question dumb?

Any expert advice would be greatly appreciated.

 

[wrestless]

Re: Table 220.13

Not sure if Im reading it right but i think it has to do with if you dont know the receptacle count then you multiply the sq ft by 4.5 and then the answer is calculated at 100 % If you do know the amount then you can use table 220.13
Example 4000 sq ft office with 60 receptacles
4000 x 3.5 x 1.25 = 17500 VA Lighting Load at 100%
60 x 180 = 10800 (10000 at 100 % 800 at 50%=10400VA + 17500 = 27900 VA.

P.S. I am very knew at this believe it or not been
an electrician for 30 years and never did a calculation in my life before Feb 2004 I am studing for a state license hope I helped you
( if im right )

[ April 15, 2004, 05:38 PM: Message edited by: wrestless ]