Bob

Above you stated that; â€œRelative to some of the other inquiries, some loads are explicitly included in the lighting load (and no additional load allowance required) per code instruction of 210.14(J), as follows:

(1) Bathroom branch circuits of 210.11(C)(3)

(2) Outdoor outlets per 210.52(E) and Basements and Garages per 210.52(G)â€ although you used 220.82 for the calculation.

I disagree with this statement in so much as if you are using the Optional feeder and service load calculation then only 220.82 will apply.

*That position is not consistent with the examples in Appendix D. Can you cite examples or other references? See remark below regarding use of 220.14 for both standard and optional calculation. Bob_NH*

In other words you answer should have been;

(B) General Loads. The general calculated load shall be not less than 100 percent of the first 10 kVA plus 40 percent of the remainder of the following loads:

(1) 33 volt-amperes/m2 or 3 volt-amperes/ft2 for general lighting and general-use receptacles. The floor area for each floor shall be calculated from the outside dimensions of the dwelling unit. The calculated floor area shall not include open porches, garages, or unused or unfinished spaces not adaptable for future use.

(2) 1500 volt-amperes for each 2-wire, 20-ampere small-appliance branch circuit and each laundry branch circuit specified in 220.52.

(3) The nameplate rating of all appliances that are fastened in place, permanently connected, or located to be on a specific circuit, ranges, wall-mounted ovens, counter-mounted cooking units, clothes dryers, and water heaters.

(4) The nameplate ampere or kVA rating of all motors and of all low-power-factor loads.

To refer back to 220.14 will mean that the standard calculation is what is being used. The two do not intermix. *The standard feeder and load service calculation is in Part III, and the optional calculation in Part IV. Neither of those include section 220.14, which is not specific to either method of load calculation. Therefore, I believe it applies generally. That is consistent with the examples in Appendix D where neither the standard nor optional calculations include the bathroom circuit as a separate element of the load. Bob_NH.*

Also it needs to be pointed out that the optional calculation can only be used for a dwelling unit having the total connected load served by a single 120/240-volt or 208Y/120-volt set of 3-wire service or feeder conductors with an ampacity of 100 or greater.

If the calculated load using the optional calculation comes up to less than 100 amps then the standard calculation must be used. *Not correct.* *The ability to use the optional calculation depends on the ampacity of the feeder or service circuit being at least 100 Amps; not on the calculated load being at least 100 Amps. *

In this case with the limited information given it wouldnâ€™t much matter as the standard calculation still comes up to less than 100 amps and 230.79(C) comes into play;

(C) One-Family Dwelling. For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes, 3-wire.