Feeder load

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Teague Allen

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New Mexico
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Electrician
I got asked this question on a practice exam and even after going into the NEC I was unable to figure out how they got the number they did please help.

A 1,600 sq ft dwelling unit contains 74 receptacle outlets including 14 receptacles in the kitchen, laundry, and dining areas. Using the standard calculation what is the computed feeder load for lighting receptacle, small appliance, and laundry loads in volt amps for this dwelling?

Answer: Table 220.12, 220.52(A), 220.52(B) 9,300 - 3,000 =6,300 VA---- 6,300x0.35 = 2,205 VA---- 3,000 + 2,205 = 5,205 VA. In the NEC for dwelling, it's 3va per sq ft, 1500va for small appliances, 1500va for laundry. I don't understand how they got the 9300 and why subtract 3000 from it, and I don't understand why the 6300 was multiplied by .35 and why was the 3000 added to 2205? Honestly, I don't understand the answer at all.
 
@Teague Allen
1600 x 3 = 4800
2 kit 1500 = 3000
laundry= 1500

4800 +3000 + 1500 =9300

1st 3000 @ 1000% = 3000
rest a7 35% 9300- 1st 3000 = 6300
6300 x .35 etc......
 
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Look at table Table 220.42 Lighting Load Demand Factors

220. 52 allows laundry and kit recep. to be used in this table

220.52 Small-Appliance and Laundry Loads — Dwelling Unit.
(A) Small-Appliance Circuit Load. In each dwelling unit, the
load shall be calculated at 1500 volt-amperes for each 2-wire
small-appliance branch circuit as covered by 210.11(C)(1).
Where the load is subdivided through two or more feeders, the
calculated load for each shall include not less than 1500 voltamperes
for each 2-wire small-appliance branch circuit. These
loads shall be permitted to be included with the general lighting
load and subjected to the demand factors provided in Table
220.42.
Exception: The individual branch circuit permitted by 210.52(B)(1),
Exception No. 2, shall be permitted to be excluded from the calculation
required by 220.52.
(B) Laundry Circuit Load. A load of not less than 1500 voltamperes
shall be included for each 2-wire laundry branch
circuit installed as covered by 210.11(C)(2). This load shall be
permitted to be included with the general lighting load and
shall be subjected to the demand factors provided in Table
220.42.
Click to expand...
 
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