GENERATOR WATTAGE CALCULATOR
Depending on how you will use your generator, there are different categories to meet your needs. This can include recreation, home standby and construction. Honda also offers Inverter Generators. Inverter generators are smaller and lighter as power is created electronically and not through a conventional alternator. Inverter power offers the cleanest power output, ideal for sensitive electronic devices.
If you want a generator for home standby, for example, if you want to run your refrigerator, you?ll need at least 2500 watts or more. And if you want to use a transfer switch so that power can go directly into your home, you?ll want a generator with at least 3000 watts.
You?ll also need to consider the maximum and rated power of the generator. This is important depending on what items you want to run off of your generator. Items such as toaster, lamps, and coffee makers are resistive, or constant loads and their total load can be calculated at amps x 1. Items such as saws and drills are reactive loads and while the running load may be small, the starting load should be calculated at running amps x 3. Remember, after the initial start less power is required for actual operation.
Always remember that simple power management will allow a smaller generator to do a big job. Very seldom are all tools or appliances operating simultaneously. When calculating power requirements, consider the starting requirements are only for the initial start and then additional tools may be operated in addition.
Remember Ohm?s Law from High School Physics? Watts = Volts x Amps Amps = Watts/Volts
So if you have two of the numbers (e.g. volts, amps) then you can find out the other (e.g. watts). This can help you to determine the rated power that you?ll need from your generator.
|
AVERAGE WATTAGE REQUIREMENT GUIDE (AMPS X VOLTS = WATTS) |
Household
|
Running Wattage Requirements
|
Additional Wattage Required For Starting |
|
Coffee Maker
|
1750
|
0
|
| Dishwasher - Cool Dry |
700
|
1400
|
| Electric Fry Pan |
1300
|
0
|
Electric Range - 8-inch element
|
2100
|
0
|
Microwave Oven - 625 watts
|
625
|
800
|
Refrigerator or Freezer
|
700
|
2200
|
Automatic Washer
|
1150
|
2300
|
| Clothes Dryer - Electric |
5750
|
1800
|
| Furnace Fan, gas or fuel oil |
| 1/8 Horsepower |
300
|
500
|
| 1/6 Horsepower |
500
|
750
|
| 1/4 Horsepower |
600
|
1000
|
| 1/3 Horsepower |
700
|
1400
|
| 1/2 Horsepower |
875
|
2350
|
| Lights |
as indicated on bulb
|
0
|
Radio
|
50 to 200 |
0
|
| Sump Pump |
| 1/3 Horsepower |
800
|
1300
|
| 1/2 Horsepower |
1050
|
2150
|
| Television - Color |
300
|
0
|
| Central Air Conditioner - 10,000 BTU |
1500
|
2200
|
Contractor
|
Running Wattage Requirements
|
Additional Wattage Required For Starting |
| Air Compressor - 1 Horsepower |
1500
|
4500
|
Bench Grinder - 8 inches
|
1400
|
2500
|
Hand Drill - 1/2 inch
|
600
|
0
|
High-pressure Washer - 1 Horsepower
|
1200
|
3600
|
| Circular Saw, Heavy Duty - 71/4 inches |
1400
|
2300
|
| Electric Chain Saw - 14 inches, 2 Horsepower |
1100
|
0
|
| Table Saw - 10 inches |
1800
|
4500
|
| Drills |
| 3/8 inch 4 amps |
440
|
600
|
| 1/2 inch 5.4 amps |
600
|
900
|
Industrial Motors
|
Running Wattage Requirements
|
Additional Wattage Required For Starting |
| Split Phase |
| 1/4 Horsepower |
600
|
1000
|
| 1/2 Horsepower |
875
|
2300
|
| Capacitor Start Induction Run |
| 1/3 Horsepower |
720
|
1300
|
| 1 Horsepower |
1600
|
4500
|
| Capacitor Start Capacitor Run |
| 11/2 Horsepower |
2000
|
6100
|
| Fan Duty |
| 1/4 Horsepower |
650
|
1200
|
Farm Equipment
|
Running Wattage Requirements
|
Additional Wattage Required For Starting |
| Electric Fence, 25 miles |
250
|
0
|
| Milk Cooler |
1100
|
1800
|
| Milker (vacuum pump) - 2 Horsepower |
1000
|
2300
|
| Portable Heater (kerosene, diesel fuel) |
| 50,000 BTU |
400
|
600
|
| 90,000 BTU |
500
|
725
|
| 150,000 BTU |
625
|
1000
|
| Battery Charger |
| 15 amp |
380 |
0
|
60 amp with 250-amp boost
|
1500/5750 |
0
|
100 amp with 300-amp boost
|
2400/7800
|
0
|
| Electric Welder |
| 200 amp AC |
9000 |
0
|
| 230 amp AC, at 100 amp |
7800 |
0
|
| Air Compressors |
Running Wattage Requirements |
Additional Wattage Required For Starting |
| 1/2 Horsepower |
975 |
1600
|
| 1 Horsepower |
1600 |
4500
|
Computers
|
Running Wattage Requirements
|
Additional Wattage Required For Starting |
| Desktop |
600 to 800 |
0
|
| Laptop |
200 to 250 |
0
|
| Monitor |
200 to 250 |
0
|
| Fax |
600 to 800 |
0
|
| Printer |
400 to 600 |
0 |
|