To Select an Inverter from that has enough power for your application, add the watts for items you may want to run at the same time. Use the total wattage, plus 10% to 20%, as your minimum power requirement.
Note: The wattages given below are estimates. The actual wattage required for your appliances may differ from those listed. Check the nameplate on the appliance to determine the actual wattage required.
* Appliances and tools with induction motors (marked * in tables) may require from 3 to 7 times the listed wattage when starting. The start-up load of the appliance or tool determines whether an inverter has the capability to power it. Be sure to check the specific wattage requirements and operating instructions for appliances / tools to be used.
F.Y.I. ….. (conversion formula: Watts ÷ 120 = Amps …….. Amps x 120 = Watts)
Common Appliances
Appliance Est. Watts
Appliance Est. Watts
Coffee pot (10 cup) 1200 VCR 40-60
Coffee pot (4 cup) 650 CD or DVD Player 35
Toaster 800-1500 Stereo 30-100
Cappuccino Maker 1250 Clock Radio 50
Coffee Grinder 100 AM/FM car cassette 8+
Blender 300 Satellite dish 30+
Microwave (600 to 1000 W cooking power) 1100-2000W(elec. consumption) Vacuum cleaner 300-1100
Waffle iron 1200 Mini Christmas lights (50) 25
Hot plate 1200 Space Heater 1000-1500
Frying pan 1200 Iron 1000
Toaster Oven 1200 Washing machine 920
Blow dryer 900-1500 12″ 3 speed table fan 230
– laptop
– pc & monitor
– printer-inkjet
60-75 TV – 25″ color
– 19″ color TV or monitor
– 12″ b&w
13″ color TV/VCR Combo 300
*Refrigerator/Freezer 600 Game Console (X-Box) 100
*Freezer 500-800 *Furnace Fan (1/3hp) 1200
Common Tools
Tool Est. Watts
Appliance Est. Watts
Jig Saw 300 1/4″ drill 250
Band Saw 1200 3/8″ drill 500
Table Saw 1800 1/2″ drill 750
6 1/2″ circ. saw 1000 Shop Vac 5 hp 1000
7 1/4″ circ. saw 1200+ *Sabre Saw 500
8 1/4″ circ. saw 1800 *Portable Grinder 1380
Disc Sander 1200 *Electric Chain Saw 14″ 1200
Makita Chop Saw 1550 *Airless Sprayer 1/2 hp 600
Makita Cut Off Saw 1000 *Air Compressor 1 hp 2000
Pumps and Air Conditioners
Pump Running Starting
Air Conditioner
*Well Pump 1/3 hp 750 1400-3000 *7000 BTU to 10000 BTU
Running: 1000-1500. Starting: 2200-5000.
(A/C’s are a very difficult load because of the high start-up surge. Use the Locked Rotor Amps to determine the start up surge requirement).
*Well Pump 1/2 hp 1000 2100-4000
*Sump Pump 1/3 hp 800 1300-2900
*Sump Pump 1/2 hp 1050 2150-4100

How to read the utility electric meter!
Most electric meters are clockface, which means they use clockfaces instead of actual numbers. There are usually five clocks. Reading the clock faces from left to right, note the number the hand is pointing to. If the hand is between two numbers, note the lower number. If the number on each meter left to right was 1 2 3 4 5. Than your meter read is 12,345 KWh. And the next month it was 1 2 4 4 5, you would have used 100 KWh.

These are some approximate wattage values for appliances.
Appliance and wattage
Lighting – Emergency= 500 Watts
Lighting – Basic= 1200 Watts
Lighting – Full= 4000 Watts
Furnace – Gas= 750 Watts
Electric Heat= 5000 Watts
Heat Pump= 5000 Watts
Electric Water Heater= 5000 Watts
Security System= 20 Watts
Portable Radio= 15 Watts
Cordless Telephone= 15 Watts
Refrigrator – 20 Cu Ft= 800 Watts
Freezer – 20 Cu Ft= 550 Watts
Sump Pump= 900 Watts
Well Pump ½ HP= 1000 Watts
Well Pump 1HP= 2000 Watts
Garage Door Opener ½ HP= 400 Watts
Microwave Oven 800W= 1200 Watts
Microwave Oven 1000W= 1500 Watts
Coffee Maker= 900 Watts
Dishwasher= 1400 Watts
Toaster= 900 Watts
Computer= 250 Watts
Electric Range-1Burner= 1400 Watts
Electric Range Oven= 7500 Watts
TV – 13″ Color= 70 Watts
TV – 32″ Color= 170 Watts
VCR= 60 Watts
Stereo System= 140 Watts
Clothes Iron= 1100 Watts
Electric Clothes Dryer= 6000 Watts
Gas Clothes Dryer= 720 Watts
Washing Machine= 1000 Watts
Hair Dryer= 1600 Watts
Air Conditioning 1 Ton= 2000 Watts
Air Conditioning 2 Ton= 3000 Watts
Air Conditioning 3 Ton= 4500 Watts
Window A/C= 2000 Watts
Ceiling Fan= 100 Watts
Vacuum Cleaner= 780 Watts
Central Vacuum= 1750 Watts

Know what you want to calculate. This can seem difficult but it’s really not too hard once you learn the terms. Most electrical appliances are rated with watts, while some use amps. To convert amps to watts, multiply the number of amps by 120. You do this because U.S. home electric outlets use 120 volts, and volts multiplied by amps equal watts. The number you want to find is how many kilowatt hours (kWh) you are using. That is what you meter reads and what you are ultimately billed for.
Create a log of what electrical appliances you use and how long you use them at a time. Keep in mind things that you do not actively (or regularly) control like heating or cooling units, water heaters, freezers, and refrigerators. Make a list for 5 straight days of all the appliances you used, to find a good average on each.
Check the labels on your electrical appliances. This is a start to calculate your electrical load and is a good way to get an idea of how much power each appliance uses. One thing to remember is that the number on the label is the maximum watts that appliance will use in an hour, so a refrigerator for instance will only use a small amount of power unless the compressor is running at which time it will use closer to the maximum power.
Estimate the amount of watts you use per appliance a day. If you need help for appliances like heating and cooling units, water heaters or other passive appliances, you can find many estimations on the Interwebs.
Calculate the kWh use for each appliance. The formula for kWh is watts multiplied by hours used and then divided by 1000. For instance, a 100-watt light bulb used for 10 hours would use one kWh.
Add all of the kWh totals from your appliances to get an idea of your electrical load that you use every day.


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