code calculations
- Thread starter reno
- Start date
- Status
bphgravity
Senior Member
- Location
- Florida
Re: code calculations
I have seen it done both ways, however I believe the correct way is to apply the demand allowances per 220.13 to the non-continuous receptacle loads and add then add the whole portion of the continuous loads.
I have seen it done both ways, however I believe the correct way is to apply the demand allowances per 220.13 to the non-continuous receptacle loads and add then add the whole portion of the continuous loads.
- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
Re: code calculations
That table and the paragraph that calls upon its use is limited in scope to receptacle outlets. I don?t think that the concept of ?continuous loads? applies to receptacle outlets. Or perhaps a better way to put it is that any lamp or other device that might be plugged into a receptacle outlet, and that might be turned on for more than 3 continuous hours, has already been taken into account in the 180 VA number.
That table and the paragraph that calls upon its use is limited in scope to receptacle outlets. I don?t think that the concept of ?continuous loads? applies to receptacle outlets. Or perhaps a better way to put it is that any lamp or other device that might be plugged into a receptacle outlet, and that might be turned on for more than 3 continuous hours, has already been taken into account in the 180 VA number.
bphgravity
Senior Member
- Location
- Florida
Re: code calculations
I too have never considered applying continuous loading to receptacle, however, in Stallcup's Electrical Design Book, published by the NFPA , he clearly shows calculating receptacle loads for both continuous and non-continuous operation. This is based on the requirements of 230.42(A)(1).
I also have a Tom Henry Electrical Calculations Workbook that does not apply a continuous loading factor to receptacles.
In conclusion, I don't think one could assume or apply a continuous loading to a receptacle unless it is specifically stated or determined to be continuous by plans or specifications.
I too have never considered applying continuous loading to receptacle, however, in Stallcup's Electrical Design Book, published by the NFPA , he clearly shows calculating receptacle loads for both continuous and non-continuous operation. This is based on the requirements of 230.42(A)(1).
I also have a Tom Henry Electrical Calculations Workbook that does not apply a continuous loading factor to receptacles.
In conclusion, I don't think one could assume or apply a continuous loading to a receptacle unless it is specifically stated or determined to be continuous by plans or specifications.
- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
Re: code calculations
Bear in mind that publication by the NFPA only means that they get the money for sales of the book. It does not mean that the book bears the same weight of authority as the NEC itself.
I agree. I will also submit that this requirement is not often included in the plans and specs.
- Status