Welder/Generator/Air Compressor Combo Units Are Evolving

Years ago, it was big news when a manufacturer added an aircompressor to a welder/generator. Today, OEMs are engaged in an armsrace to outfit their equipment with as much functionality as possible.Stakes have been raised with battery chargers, jump starters andhydraulics. It makes sense: Whether your work is dedicated to serviceand repair or you’re a tradesman with a “power box” on the back of yourtruck to handle whatever repairs or challenges come your way — newequipment on the market today increases your capacity for work withoutexpanding your footprint. And it’s now more efficient than ever.

“Themulti-functional capabilities [with these combination units] allows forconvenience, more bed space, lower cost output, lower fuel consumptionand greater productivity — all features that are critical to ourcustomers,” says Chris Sloan, marketing manager with Vanair.

A Focus on Efficiency

Arguablythe strongest value proposition for combination units is lower owningand operating costs. A combination unit features a single engine tomaintain and costs less than if you were to buy and maintain separateunits — and the single unit takes up less space. There are now even moreextensive all-in-one options on the market, such as the Air N Arc I-300from Vanair, that includes a welder, generator, air compressor,hydraulic pump, battery charger and jump starter in a single footprint. Miller Electric Mfg. Co.has further extended its larger, low-speed diesel line to feature dualoperating systems that run completely independent of each other tocreate two distinct workstations — effectively doubling output withoutdoubling space.

Even with the recent drop in fuel prices, fuelefficiency remains a top purchase driver for anyone runningengine-driven equipment. It has as much to do with productivity as itdoes cost savings.

“The thing that comes to mind right off the batis fuel consumption — the ease of having longer run times without theneed for refueling,” says Christopher Cramer, owner of Metal Connection LLC in Oshkosh, Wis. “It doesn’t take long to fuel up, but it is a hassle.”

“Greaterfuel efficiency equates to longer runtimes for welding operators on thejob, which can help increase productivity,” says Travis Purgett,product manager with Miller. “Less time spent on refueling means moretime doing other value-added activities.”

OEMs have engineeredthis equipment to be more fuel efficient. The first machines withelectronic fuel injection (EFI) were introduced about five years ago,and most major manufacturers, including Miller, Lincoln Electric andVanair, have that option available. EFI offers numerous benefits,including no choke, better starting in cold environments and reducedfuel deterioration — but the biggest benefit is an optimized blending ofair and fuel for efficient combustion/reduced fuel use. More advancedfuel management technology, however, has further revolutionized theefficiency of these machines. Miller, for instance, has implemented anumber of speed-governing technologies that allow the machines to burnonly as much fuel as is needed for the job at hand.

“A commonapplication is welding a 1/8-in. 7018 stick electrode,” says Purgett.“With speed governing technology, welding operators can complete thistype of welding all day and never have the machine come out of idle. Anystick, TIG or MIG application that runs at 150 amps or lower can becompleted at idle, or 2,400 rpm. A machine with speed-regulatingtechnology can save about $460 per year in fuel costs compared to amachine without it.”

Welding

A welder/generator comboprovides contractors with the capability of running most weldingprocesses. Stick welding remains the most common. Wire processes —specifically self-shielded flux cored welding — are also popular infield applications. Both stick and self-shielded flux cored arepreferred because they provide their own weld protection (wire processesthat require gas shielding need extra equipment and are subject to windblowing away the shielding). All welder/generators can perform stickwelding. Wire processes require a constant voltage (CV) output to workoptimally with wire feeders or spool guns. These machines are capable ofTIG welding, but it is generally preferred to TIG weld with adedicated, inverter-based machine (which can be run off of the generatorpower of some of the higher-output welder/generators).

“Understandwhat the output requirements are for the wires you use and the outputcapabilities of the units you have or are considering,” says Purgett.“Typical-use duty cycle is higher when wire welding than when stickwelding due to the continuous feed capability of wire versus having toreplace the stick electrode when it burns down.”

One of thegeneral concerns about welder/generators is degradation of the weldingarc when another tool is engaged off of the machine’s auxiliary power.Miller and Vanair both tout solutions that eliminate the problem. Milleroffers machines with two separate generators (one for welding and threephase, one for one phase) in its large frame, low-speed diesel line;and a generator with separate windings for weld and auxiliary power inits Trailblazer line. Vanair features two separate independentgenerators throughout its product line, which allows for dualfunctionality such as welding and auxiliary lighting. With thistechnology, degradation is less of a concern.

“Our systems havevery sophisticated and reliable engineering and computer logic withinthem,” says Sloan. “This helps in determining horsepower loads whenengaging multiple product features.”

Auxiliary Power/Battery Charger/Jump Starter

Mosthand tools on jobsites can be operated at the lower end of agenerator’s capacity. Larger tools and equipment, however, requiregreater outputs — and that’s where it’s important to know the differencebetween peak and continuous power — and how it relates to your tools.Peak wattage correlates to startup power — the energy required to getthe tool cranking. Continuous watts refer to the power required to runthe tool.
For basic jobsite tools, Miller has introduced an optionaltechnology on select models called Excel Power that providescontractors 2,400 watts or pure 120-V, 60-hertz generator powercompletely separate from the machine’s standard generator. This allowsthe user to operate tools below that capacity without the machine everleaving idle. Cramer — whose business focuses on mobile fabrication andsite repair — pays close attention to auxiliary power when specifyingwelder/generators. The high end of that demand revolves around plasmacutters.

“Having the auxiliary power to run the larger plasmacutters is important,” says Cramer. “12,000 to 15,000 watts is ideal.With my Trailblazer 302 AirPak, I can run a [rated 60-amp] plasma cutterat 50 out of 60 amps. You can run it wide open at 60 amps, but ifyou’re running it and it’s warm out, and you get heat build up, I canrun about 50 amps, which gives you 1/2-in., maybe 5/8-in. cuttingcapacity.”

Most OEMs in this space now offer battery charger/jumpstarter capability, which is important to everyone inconstruction-related industries, as most operate a fleet of trucks orequipment. It’s just one more way these combo units have become moreuseful. “Depending on the product, Vanair features a 12-V charge and or a12V/24-V boost. This enables the customer to jump start their truck’sengine while our auxiliary power can maintain the truck’s own batteryand can operate work and emergency lights while the truck engine is offsaving on fuel and operating costs,” adds Sloan.

Air Compressor/Hydraulics

Aircompressor functionality varies based on make and model, but mostfeature more than enough cfm/psi at 100 percent duty cycle to handlebasic air tools: grinders, shears, impact wrenches, etc. Air needs willincrease as you begin using larger industrial tools or consider carbonarc gouging.

Hydraulics are relatively new to this productcategory. Miller came to market with its EnPak product line, which didnot feature a built-in welder, but did include hydraulic functionalityfor powering service truck cranes, and a Hydraulic Tool Control (HTC)for operating independent hydraulic tools. Vanair’s I-300 features abuilt-in welder with a variable displacement hydraulic piston pump,compatible with both open center and closed center systems. For Purgett,selecting the right machine comes down to a practical understanding ofspec demands and future ambitions.

“Understand your needs, presentand future,” says Purgett. “If you are planning to purchase awelder/generator for the first time, be sure to understand the auxiliarypower, weld and compressed air requirements. Consider what your needswill be one, two and even five years in the future.”

That advicegoes for both specs/capacity and the capability of adding more tools andcapabilities to your skill set. For Cramer, he sees the investment ingreater functionality as a platform for greater profitability. “For anadditional $5,000 investment, your ROI is very quick.”

Bill Elverman is a contributing writer to Compact Equipment.