Check on Load Calculation

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Little Bill

Little Bill

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Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
I need some oversight on my load calculation. Here is what I came up with.
3400 sq ft @ 3va = 10200VA
4 (assuming) SABC @ 1500VA = 6000VA
2 Laundry circuits @ 1500VA = 3000VA
Double oven @ 9600VA =9600VA
2 Dish washers @ 1200VA = 2400VA
2 Dryers @ 5000VA = 10000VA
Total General Load = 41200VA
First 10000 kVA @100%
40100 - 10000 = 31200VA
31200 x 40% = 12480VA
12480VA + 10000 = 22480VA
20400VA HVAC load (largest of AC vs Heat on 2 units)
20400VA + 22480VA = 42880VA
42880VA ÷ 240V = 179A

If this is correct then I could use a 200A service.
 
Garbage disposal? Garage door openers? Water heater? Built in Microwave? Hydomassage tub? Pumps of any kind (well, sump)?
 
suemarkp said:
Garbage disposal? Garage door openers? Water heater? Built in Microwave? Hydomassage tub? Pumps of any kind (well, sump)?
Click to expand...
I've never added garage door openers. They pull very little and are now DC motors. Water heater is gas, gas cooktop, no hydro tub, garbage disposal?
 
Little Bill said:
I need some oversight on my load calculation. Here is what I came up with.
3400 sq ft @ 3va = 10200VA
4 (assuming) SABC @ 1500VA = 6000VA
2 Laundry circuits @ 1500VA = 3000VA
Double oven @ 9600VA =9600VA
2 Dish washers @ 1200VA = 2400VA
2 Dryers @ 5000VA = 10000VA
Total General Load = 41200VA
First 10000 kVA @100%
40100 - 10000 = 31200VA
31200 x 40% = 12480VA
12480VA + 10000 = 22480VA
20400VA HVAC load (largest of AC vs Heat on 2 units)
20400VA + 22480VA = 42880VA
42880VA ÷ 240V = 179A

If this is correct then I could use a 200A service.
Click to expand...
Is this a 2 family? Article 220.85 might effect calculation. Also did you apply the demand factor from 220.42 to your lighting/general purpose receptacle calculations?
 
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