Example No. D11 Mobile Home (See 550.18)
A mobile home floor is 70 ft. by 10 ft. and has two small appliance circuits; a 1000-VA, 240-V heater; a 200-VA, 120-V exhaust fan; a 400-VA, 120-V dishwasher; and a 7000-VA electric range.
Lighting and Small Appliance Load
|
Lighting (70 ft. x 10 ft. x 3 VA per ft.2) |
2100 VA |
|
Small appliance (1500 VA x 2 circuits) |
3000 VA |
|
Laundry (1500 VA x 1 circuit) |
1500 VA |
|
Subtotal |
6600 VA |
|
First 3000 VA at 100% |
3000 VA |
|
Remainder (6600 VA - 3000 VA) at 35% |
1260 VA |
|
Total |
4260 VA |
|
|
Amperes per Leg
|
Leg A |
Leg B |
|
|---|---|---|
|
Lighting and appliances |
17.75 |
17.75 |
|
Heater (1000 VA ÷ 240 V) |
4.20 |
4.20 |
|
Fan (200 VA x 125% ÷ 120 V) |
2.08 |
|
|
Dishwasher (400 VA ÷ 120 V) |
3.30 |
|
|
Range (7000 VA x 0.8 ÷ 240 V) |
23.30 |
23.30 |
|
Total amperes per leg |
47.33 |
48.55 |
Based on the higher current calculated for either leg, a minimum 50-A supply cord would be required.
For SI units, 0.093 m2 = 1 ft2 and 0.3048 m = 1 ft.