Service Calculation

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GSXR600

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Hi,
I am taking a service calc. class and was wondering what would you guys do for a dedicated receptacle if you are not sure what is being plugged into it? Would you count it at 180VA or 2400 VA? Also would these be subject to the demand factor?

I really appreciate your guys thoughts.
 
GSXR600 said:
Hi,
I am taking a service calc. class and was wondering what would you guys do for a dedicated receptacle if you are not sure what is being plugged into it? Would you count it at 180VA or 2400 VA? Also would these be subject to the demand factor?

I really appreciate your guys thoughts.
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Are you talking about a residential application or non dwelling unit?
 
If commercial/industrial
A receptacle is normally not considered to be a continuous load. Per NEC 220.14(I) a receptacle outlet shall be calculated at no less than 180va for each single or multiple receptacle on one strap (Or yoke).

If you are trying to find how many receptacle are permitted on a circuit, I believe you would need to no the ampacity of the circuit, then divide the VA rating by 180va. Example: Circuit ampacity=15A @120v=1800va. 1800v a/180va=10 yokes.
On your question of demand, read NEC 220.14 (H) and (I). Then 220.44. This should help you.
 
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for instance on alot of commcercial projects the owner request dedicated receptacles for who knows what?? Are these to be calculated at 180 VA each of should they be considered at worse care senario for 220.14 (a)?? If there were calcuated per 220.14 (a) they would not be subject to the demand factor.
 
GSXR600 said:
for instance on alot of commcercial projects the owner request dedicated receptacles for who knows what?? Are these to be calculated at 180 VA each of should they be considered at worse care senario for 220.14 (a)?? If there were calcuated per 220.14 (a) they would not be subject to the demand factor.
Click to expand...
As stated above, read NEC 220.44. Then re-read what I wrote. I guess I should add, if you do not know the number of receptacles involved with your feeder/service calculation then add 1va for each square foot of the building per NEC 220.14(K)2. (See 220.14K2)
 
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