GENERATOR WATTAGE CALCULATOR
Below is a list of items with typical wattages alongside. It is vital that you do not overload your generator, or serious damage can occur.
If you want a generator for home standby, for example, if you want to run your refrigerator, you’ll need at least 2500 watts. For ease of use, convenience and safety, it is recommended that a changeover switch is professionally installed into your home's electrical system. We recommend a minimum of a 5000w generator if using a changeover switch, as the generator will then be connected to the whole house.
You will have to be careful not to overload the generator. This is very important, so the total watts of the electrical appliances connected to the generator must be added up. Depending on what items you want to run off of your generator, items such as electric heaters, lamps, and coffee makers are resistive, or constant loads and their total load can be calculated at amps by just adding together the rated amperage of each appliance. However, items such as vacuum cleaners and drills are reactive loads and while the running load may be small, the starting load should be calculated at running amps x 2.5. Remember, after the initial start up, less power is required for actual operation.
Please remember that by simple power management, your 5000w generator will run your home with ease. Typically, this size generator will allow you to run lighting in 5-6 rooms, TV and one larger appliance at a time, e.g. Cooker or Washing machine. If more than one larger appliance is used at once, it may overload the generator.
Warning, certain appliances like an electric shower can be rated at upto 12kw. Be sure not to use this appliance unless you have a generator large enough to cope with this power level.
Ohm’s Law:
Watts = Volts x Amps
Amps = Watts /Volts
If you have two of the numbers (volts or amps) then you can find out the other (watts). This will help you to calculate the rated power that you willl need from your generator.
AVERAGE WATTAGE REQUIREMENT GUIDE (AMPS X VOLTS = WATTS)
Dishwasher 2000w
Microwave Oven 650 watts cont, 1000w to start
Refrigerator or Freezer 1200w
Washing machine 2000w
Lights: wattage as indicated on bulb
Radio 50 to 200w
Colour TV 300w
Electric Showers can be rated at 8-12kw. Do not use with a generator rated below this figure.
Air Compressor 1 Horsepower 1600w cont,4500 to start
Bench Grinder 8 inch 1400w cont, 2500 to start
13mm Hand Drill 600w cont, 900w to start
PETROL GENERATORS
