Voltage Regulating Generators Change What’s Possible on the Jobsite

Small generators, notably inverter generators, reduce the size, weight and sound of a typical generator, while also producing stable and consistent power — all attributes that have revolutionized the jobsite. Because of this product segment, individual workers can now be equipped with individual power sources, offering a ton of jobsite flexibility.

“The benefits of lighter weight units in smaller package sizes is driving a real transformation on construction jobsites,” says Tom Pernice, senior marketing strategist, Honda Power Equipment, which markets a complete line of portable generators for commercial applications between 1,000 and 10,000 watts of power. All Honda generators are powered by advanced Honda four-stroke engines and incorporate technology to make them among the world’s quietest. “Smaller, lighter inverter generator models are easier to transport, can be located closer to the user and also can be connected in parallel to double the output when needed. So, the ability for contractors to generate the power needed without sacrificing portability is a major shift in how generators are being used on jobsites.”

But the flexibility and convenience of distributed power on the job isn’t the only factor that’s pushed the hand-held portable sector to the top of the generator market. The National Electric Code (NEC) has updated its rules concerning Ground Fault Circuit Interrupter (GFCI) receptacles, so it is important for buyers to check local codes when selecting a new generator. Also, the other equipment on the jobsite today is equipped with more advanced and sensitive electronics, all of which needs quality inverter generators that are up for the task. Many tools now include electronic components that require stable power, and contractors using low-cost generators may not realize damage is occurring to their tools or equipment until the damage is done, according to Pernice.

“While all the advances are significant, matching power needs with a high-quality generator output that can protect sensitive equipment, offer portability, durability and reliability is important and will give the most value to the owner,” Pernice says.

The 2,000- to 4,000-watt range of inverters is becoming a leader due to its quiet, reliable power and stable voltage supply for hand tools and even for those aforementioned sensitive electronics, including computers and other office equipment, according to Pam Meyer, Subaru Industrial Power Products equipment sales manager. The complete Subaru line of portable generators includes industrial, commercial and inverter models ranging in power from 2,900 to 13,000 watts and includes a five-year warranty. Its inverter generator line sits between 3,200 and 4,300 watts.
Inverter Info

So, if a small, high-quality generator is important for powering sensitive equipment on today’s jobsite, what are you looking for? It starts with Automatic Voltage Regulation (AVR) or inverter technology, according to Pernice.

Conventional generators equipped with AVR constantly monitor load changes and adjust output to produce a clean consistent sine wave. AVR constantly adjusts the fields and adjusts to changing loads to maintain the rpm of the generator at 60 cycles — which provides good quality power. On the other hand, inverter generators produce the best quality power with the smaller units having the added advantage of lighter weight with quieter operation.

“Generators featuring inverter technology process the raw power produced by the generator and pass it through a special microprocessor to provide the most stable power,” Pernice says. “This also provides load sensitive operation, allowing the generator to adjust output as needed, reducing fuel consumption and further reducing the sound level.”
The stable power produced by inverter generators is a nice benefit. These generators run electricity through an inverter board to produce clean, purely manufactured power that minimizes voltage fluctuations that can be harmful to electronics.

“One of the reasons we updated our SGX generator line was because we saw the need in the market for a generator that fits between the ‘throw away’ consumer models and the high-end premium models,” Meyer says. This line really has all the basic features that a moderate industrial user would need: an automatic voltage regulator system for precise voltage control output, a low-tone muffler and a two-wheel kit for enhanced portability.

As far as power goes, generator output is directly related to engine size. Pernice recommends comparing engine displacement to claimed power output.

“If you find larger claimed output from smaller displacement engines, beware,” he says.

Inverter generators, which tend to run as much as 13 decibels quieter than conventional models, are also great options for operation in populated neighborhoods or indoor commercial facilities.  For example, many conventional generators are rated 65 to 75 decibels — in the range of normal speech (60 dBa) to a running vacuum cleaner (70 dBa) — comparatively much quieter than chainsaws (110 dBa) and jet engines (130 dBa). Subaru’s inverters produce 58 to 62 decibels at full rated output for quieter operation. Honda generators for typical residential use average 64 to 73 decibels, with the Super Quiet Series inverter generator models operating at noise levels as low as 49 decibels, about the sound threshold experienced in a private office.

Choose Wisely

Generators have a broad range of applications, so understand the job at hand and plan accordingly. Meyer recommends starting with a list of what will run off the generator for each project you might undertake. Check the wattage and multiply it by the number of units to be used.

“For example, two hand drills that use 600 watts each would need 1,200 watts of power to run both simultaneously,” she says. “Some tools take more energy to start than they do to run. This wattage surge also should be taken into account when determining the total power needed. Hand drills and electric welders run on a constant wattage while circular saws and air compressors need greater power to start. To allow for error or future power requirements, contractors may want to add 10 percent to the total wattage they have calculated to make sure they have enough power for the job.”

All of this will help to determine what should be rented or purchased — an inverter, commercial or industrial generator or a mix of the three — and what power output will ensure you have what you need to cover all devices and tools while accounting for surges. The jobsite of today demands it.

Chris Crowell is a contributing editor to Compact Equipment.