#### FlyWhale

##### Member
I'm stumped on this load calculation. I can't seem to figure it out.

A single family dwelling is supplied by a 120/240v, single phase service. The dwelling has 2500 square feet and the following:

10,000 VA fixed space heater at 240v
11,000 VA range at 240v
4,500 VA clothes dryer at 240v
800 VA disposal motor at 120v
Two non-motor, 120v, not fastened in places appliances, with a total combined nameplate rating of 2,500 VA.

What would be the total minimum load using the standard method?

#### Little Bill

##### Moderator
Staff member
Can you show us your work and how you figured it, and maybe we can direct you from there?

#### FlyWhale

##### Member
Can you show us your work and how you figured it, and maybe we can direct you from there?

I'm on mobile so I'll do my best

2,500 ft² x 3VA/ft² = 7500VA. Per 220.12

10,000 VA fixed space heater @ 100%. Per 220.51

11,000 VA range turns to 8 kW per table 220.55
Also to mention kVA shall be considered equivalent to kW in 220.55
So...8000VA?

4,500 VA clothes dryer turns to 5000 VA. Per 220.54

The 2 non-motor appliances at 2,500 VA

800 VA x 1.25 = 1,000 VA per 220.50 which took me to 430.24 (1)

10,000 fixed space heater
8,000 range
5,000 clothes dryer
1,000 disposal motor
2,500 non-motor appliances
3,000 (1,500 x 2) per 220.52 (a)
1,500 per 220.52 (b)

Using the example in Annex D...
7,500 + 3,000 ( 220.52 (a)) + 1,500 ( 220.52 (b)) + 10,000 + 1,000 + 2,500

= 25,500

3,000 VA @ 100% per table 220.42
25,500 VA - 3,000 VA = 22,500 @ 35% = 7,875

7,875 + 8,000 + 5,000 = 20,875 VA

20,875 is not what I'm supposed to get.... it's supposed to be 32,650 VA.

#### Dell3c

##### Member
2500x3=7500
7500
3000SA
1500LA
=12000va
12000
-3000
=9000
x0.35
3150va
+3000
=6150GL
(6150GL + 5000dryer + 8000range + 1000disp. + 2500va 10000heat)=32650VA

#### FlyWhale

##### Member
2500x3=7500
7500
3000SA
1500LA
=12000va
12000
-3000
=9000
x0.35
3150va
+3000
=6150GL
(6150GL + 5000dryer + 8000range + 1000disp. + 2500va 10000heat)=32650VA
I see.... can you explain why they are added in that specific fashion?

#### Dell3c

##### Member
Table 220.42 Dwelling units..
220.52 Small Appliance & Laundry " The Last sentence" : These loads shall shall be permitted to be included in the general lighting load and subjected to the demand factors provided in Table 220.42

Last edited:

#### FlyWhale

##### Member
Table 220.42 Dwelling units..
I understand that part. I suppose what I'm asking is where did the standard method come from? ...as in, why are the appliances added in afterwards?