Properly use Table 220.84

[Electricalhelp]

I was curious how I would apply the demand factor using Table 220.84.

The existing unit has over 62 Dwelling Unit, and they want to add an additional 20 Units

If I know the total load for the existing unit, I was wondering if I can use the Demand factor of 23% (62 and Over), which will include the existing and 20 new units in my calculations.

Or if each floor has 20 Apartments, do I have to use the demand factor of 38% for each floor. Than add the total loads up for each floor at the end.

 

[charlie b]

Pick any point in the distribution system, and calculate the load downstream of that point. You use the demand factor associated with the number of units that are downstream of that point. So it is not a matter of how many units are on a floor, unless each floor has a distribution panel that feeds all unit branch panels on that floor. For calculating the service load, you count all the units.

 

[Electricalhelp]

Thank you for the help.

Each floor has a distribution panel, so I will need to use the demand factor for each floor to see if there is enough capacity on the panel to add the new apartments on each distribution panel.