How to Use a Standby Generator Load Calculator

standby generator load calculator

You can use the wattage of the largest motor to size the generator. You can also use starting current for non-motor loads to calculate the total watts. Once you have these values, multiply them by 1000 for kilowatts. This is a common sizing method for retail locations.


If you are planning to install an automatic transfer system for your facility, you will need to understand how to size a standby generator. Fortunately, there is a simple tool available that will do all the calculations for you. The GenSizer standby generator load calculator can help you determine how much power your generator should have for the load you have entered.

The program will also let you input specific parameters. It has an extensive database that gives you current performance data and a built-in help tool. It can also provide a direct link to your local distributor.

Variables to consider

A generator load calculator can be useful in determining your total power requirements, but it is important to input all of the correct data. This information will affect the size of your generator and its ability to maintain your operations during outages. The calculator should account for extended idling times and other variables.

When using a standby generator load calculator, it is important to understand the relationship between the three variables: watts, volts, and amps. A single-phase generator can handle small retail businesses, but an industrial plant needs three-phase power.

Using a standby generator load calculator can help you find the correct size of generator for your home or business. There are two types of wattage meter that you can use. You can also use the energy statement for your property to determine the number of square feet. In the case of a retail business, you should use ten watts per square foot, while commercial facilities should use five watts per square foot.

Starting wattage

If you’re buying a standby generator for your home, you’ll need to understand three different specs: running wattage, starting wattage, and surge wattage. Starting wattage is needed to power an appliance from a dead stop; running wattage is used to keep a device running after it starts. For example, a refrigerator might need 700 watts to start but only 300 watts when running.

If you’re planning to use your generator to power a lot of devices, start by calculating the total wattage of all of the devices you’ll be running off of the generator. Once you’ve done this, multiply each one by three to get the total running wattage. If you have more than a few devices, you’ll need to increase the starting wattage of each device.

Surge wattage

A standby generator load calculator can be a very helpful tool if you’re trying to decide which size to purchase. This tool will calculate the amount of power required for a variety of different appliances. Whether you’re running a refrigerator, washing machine, or freezer, you need to know how much power you’ll need to run each one.

To determine the amount of power you’ll need, start by calculating the wattage of the largest motor. Then, multiply that number by three to get the surge wattage. This figure is different for every application. For example, if you’re installing an air conditioner in your home, you’ll need about 2,000 watts of power for it to start.

Physical dimensions

If you’re trying to determine the physical dimensions of a standby generator, you’ll want to use a calculator. You’ll also need to check the manuals for any big appliances you own. Note the starting wattage of each device, and multiply it by three to get a rough estimate of the wattage needed. Next, add up all of the devices you own, and use this figure to determine the size of your generator.

Using a standby generator load calculator will ensure that your generator is the correct size for your home. It is critical to use a generator that has enough wattage to keep all of your appliances running. It’s also a good idea to allow for some overhead to protect your generator from overload and shorting.