Appliances with electrical motors require as much as three times their rated wattage to start. So, when determining what type of generator to buy for a certain appliance, you must figure out the starting wattage the appliance requires. To do that, you need to know the volts and amps of the appliance, which are inscribed on the appliance's nameplate. The following formula can help you determine the electrical load for the generator:

Volts x amps = running watts

Running watts x 3 = starting watts

Running watts indicates the amount of electricity needed to run the appliance. Starting watts indicates the amount of electricity needed to get its motor running. The generator's wattage must be equal to or greater than the starting wattage of the appliance.

The 5,000-watt portable generator runs on a tank of gas and has outlets for appliances of different voltages. The generator's motor is started by pulling on the choke.

The 8,000-watt generator is also portable but has a more powerful 16-horsepower motor. The motor uses gas and oil as fuel. It has a starting idle and a running idle so that the machine can be adjusted to provide only the amount of power needed at a given time. This larger generator also has outlets for appliances of different voltages.