STORE LOAD CALC

[Toros]

Hi
conducting load calc forunder- remode store, a service up grade;
should I include or calculate air conditioning in continous load part of the calc????

tanx

 

[Dennis Alwon]

a/c is usually calculated at 100%. Optional method

(C) Heating and Air-Conditioning Load. The largest of
the following six selections (load in kVA) shall be included:
(1) 100 percent of the nameplate rating(s) of the air conditioning
and cooling.
(2) 100 percent of the nameplate rating(s) of the heat pump
when the heat pump is used without any supplemental
electric heating.
(3) 100 percent of the nameplate rating(s) of the heat pump
compressor and 65 percent of the supplemental electric
heating for central electric space-heating systems. If the
heat pump compressor is prevented from operating at
the same time as the supplementary heat, it does not
need to be added to the supplementary heat for the total
central space heating load.
(4) 65 percent of the nameplate rating(s) of electric space
heating if less than four separately controlled units.
(5) 40 percent of the nameplate rating(s) of electric space
heating if four or more separately controlled units.
(6) 100 percent of the nameplate ratings of electric thermal
storage and other heating systems where the usual load
is expected to be continuous at the full nameplate
value. Systems qualifying under this selection shall not
be calculated under any other selection in 220.82(C).

 

[jumper]

a/c is usually calculated at 100%. Optional method

I do not think you can use optional method for commercial.
220.18(A) would apply I believe. Easiest way is to use the MCA since it has the 125% built in, so 100% of the MCA works well IMO.

IV. Optional Feeder and Service Load Calculations
220.80 General.
Optional feeder and service load calcula-
tions shall be permitted in accordance with Part IV.

220.82 Dwelling Unit.
(A) Feeder and Service Load.
This section applies to 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.