Portable Generators

How To Correctly Size A Portable Generator

In our energy-driven society, we often take for granted that we will have a constant supply of accessible power for our appliances and gadgets. But in recent years, hurricanes and blizzards that caused outages have been a poignant reminder that we are only one downed tree or power line away from being without power.

Purchasing a portable generator is a great investment in peace of mind, and in the safety and comfort of your family in the event of a power outage. An emergency generator has the additional benefit of being easily transportable for all kinds of outdoor activities and entertaining. There are many different sizes available, so let’s discuss how to choose the portable generator that best meets your needs.

How Much Wattage do I Need?

It is very easy figure out what size generator you will need in an emergency. Using the chart below, simply add up the essential devices that you wish to run simultaneously (since the total connected load should NOT be greater than the generator’s wattage capacity).

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Image courtesy Generac

It’s crucial to keep in mind that at startup, many electrical devices need more current to start their electric motors. This initial surge may only last for a few seconds, but it must be part of your calculations when sizing a generator. To properly allow for these “starting watts,” take the starting wattage of the largest item on your list and then add it to the total running watts of the load that will be running simultaneously.  Appliances may be run by means of extension cords connected to your generator. But installed appliances in the home, or those requiring 240V, will require the generator to be connected by means of a transfer switch. Then items like furnaces and well pumps may be operated safely. A transfer switch should be installed by a qualified, licensed electrician.

You might be caught off guard a little bit by how many watts the average household appliances need to run (a toaster has a higher average running wattage than a refrigerator?!) so make sure you are factoring in everything you need to run in an emergency situation. Certain things like a refrigerator or freezer are must-haves (can’t have all that food spoiling) while TV’s and curling irons should be factored in but not counted on.

For outdoor home use consider a lower wattage generator to run things like electric chainsaws, leaf blowers, edgers and mowers. For a high usage job-site consider a more rugged high wattage machine to run most if not all of your power tools.

Generac Features

GeneracThe Generac portable generators that Koopman carries offer reliability and features not usually found on basic portable models. They come with outlet covers for protection from the elements, circuit breakers that provide overload protection, an hour meter (keeps track of total run time as well as alerting for scheduled maintenance), low oil shutdown and a convenient folding/locking handle. Additionally, the GP7500E model offers electronic start (battery included).

Ready To Go

Any generator that Koopman sells will already be fully assembled, filled with oil, test started and load tested. You won’t need to worry about removing parts from a huge box, having the all of the necessary tools, reading instructions and disposing of all of that packaging afterwards. It’s as easy as loading your new generator into your vehicle, driving it home and starting it up!

Koopman is a factory-authorized service provider, so we can help you keep your generator running well for many years to come.




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