Selecting the Right Generator
How to Select the Right Generator
One rule of thumb to understanding how much wattage is needed is to add up all the power requirements you need and add 10-20%. The amount of wattage available from a portable generator varies. Gas generators in the 3,000W to 5,000W range give you decent run time without having to refuel. This output satisfies many contractors. For bigger jobs, where electricity from the grid is not available, 6,000W to 8,000W gas generators provide all-day energy to power up tools. Extra-large 10,000W to 14,000W gas generators offer professional contractors a mini powerplant on wheels. Knowing what equipment you need to run is critical to identifying how much power you need.
Having a consistent power output with little to no fluctuations is essential to maintaining equipment. Power surges or spikes can damage the equipment you are running and the generator. Honda has a helpful wattage calculation tool that asks which tools and equipment you want to run with the generator and then calculates the starting and running wattage needed to keep it all running.
SizeWhen it comes to generators, size does matter. Generator sizes typically range from medium, large, extra-large to industrial. Contractors needing to run power tools on the jobsite will most likely need large or extra-large generators. Large generators output anywhere between 5,000W and 9,000W. They allow multiple tools to operate at one time and are still portable. Extra-large generators output over 10,000W and can cover most power tools for the day.
A rule of thumb for determining power needs is to add up the total watts of the equipment needed to operate by the generator. Use the amps x volts = watts formula, then multiply the total number of watts by three. This final number is a good approximation of startup wattage required and gives you an idea of the best size generator for your needs.
Larger generators that offer greater power push the boundaries of portability and may require some effort to move around the job. It is important to identify the right size to meet your needs. Buying a generator that is too big for your power needs not only costs more to purchase, but you end up wasting fuel, which in turn wastes money. When a generator is too large, you end up having to refuel it more than is necessary. You also end up storing more fuel on-site which means additional storage tanks.
PortabilityAs the generators increase in power output quality, they also increase in size and weight. If true portability is a determining factor, think about where you will be transporting and using your tools because that is where your generator needs to go as well. Determine whether you will move it around the worksite or park it in one general area. Keep in mind that generators up to 7,000W could weigh 200 pounds, which is still fairly portable with wheels and some muscle. When you get into the 10,000W range, a generator could be up to 400 pounds and may require a lift hook to move it around. Portability and size are inextricably linked; you lose some portability as you increase in wattage.
NoiseLet’s talk decibels. Generators can be noisy machines. But so are construction sites and making noise outside during the day does not normally pose a problem. However, when it comes to power at night, keeping the noise down is a must, especially when your site is near a residential area. Some generators are better than others at keeping quiet on the job.
OSHA ComplianceThere are potential hazards inherent with the use of portable generators, and the Occupational Safety and Health Administration (OSHA) has standards and guidelines to keep generator operators safe from harm. The biggest hazards identified by OSHA are carbon monoxide exhaust, shock or electrocution, fires, and noise or vibration. OSHA offers safety information about these hazards and how to avoid them. OSHA also has regulations for ground fault circuit interrupters (GFCI) receptacles. GFCIs help protect operators from electrocution when used on a generator with a frame that can serve as a grounding electrode. Additionally, the Environmental Protection Agency (EPA) also has three levels of emissions standards that apply to generators. Learn more here: https://www.epa.gov/regulations-emissions-vehicles-and-engines/regulations-emissions-small-equipment-tools
Quality ItemA generator is a big-ticket item. Take the time to identify your needs and select a high-quality piece of equipment that meets those needs and your budget. Your generator needs to hold up to continued use on the jobsite. Look for a quality engine with a good warranty. Fuel efficiency should be considered; just like your car, a fuel-efficient engine will cost less to operate and reduce refueling time. An engine that offers a longer run time will also save you money in fuel costs.
Don’t forget your accessories! Generator accessories will make any generator last longer and function better. Whether it is a cover to protect it from the elements, wheel kits, transfer switches to change the energy load, or proper adaptors and extension cords to extend its reach, we offer a wide array of accessories to help you get more life out of your generator.