COMMON PITFALL #1: COMPARING WELDING MACHINES BASED SOLELY ON THEIR MODEL NAMES.
Some manufacturers sidestep the IEC formula and give a name to their equipment based on an unrealistic amperage. This can steer customers into making misguided decision, which will negatively affect their ability to perform the job. When shopping for a welder, what really matters is the true welding output and horsepower. Make sure to look beyond the product name and compare the specifications of competing machines that can be found in product literature or owner’s manuals.
It’s best to compare the IEC rating of each machine. Sometimes the current ratings of two machines will match, but the voltage or duty cycles will differ. Higher voltages, duty cycles, and horsepower mean more output.
Lincoln Electric helps to eliminates this confusion by naming its Vantage® machines according to the IEC amperage class and horsepower. This gives the customer a clearer sense of what they’re getting, and ensures that they’re getting what he or she’s paying for. Further, Lincoln Electric’s Vantage engine-driven welder includes a nameplate that lists the duty cycle of the machine to help prevent confusion.
Auxiliary Output It’s also important to consider your auxiliary power needs. Engine welders also generate auxiliary (AC) power that can be used to run lights, pumps, power tools and other devices. As with welding output, it’s important to review machine specifications closely to ensure a true comparison. The two ratings often used for auxiliary power are peak power and continuous power.
COMMON PITFALL #2: NOT COMPARING AUXILIARY POWER CORRECTLY
Peak, continuous, three phase, single phase, with so many different types and ways to rate the auxiliary (AC) output of your machine, it can get very confusing. Here are a few things to remember that will help you get the amount of power you need.
PEAK POWER VS. CONTINUOUS POWER
The peak power will always be higher than continuous power, but can only be sustained for a short time (about 30 seconds or less). Peak power is needed for certain applications, such as starting pumps or other inductive loads, which can require a large in-rush current to get running After that initial surge, it settles into the lower, continuous power rating. Continuous power is the power available at a 100% duty cycle.
Always be sure you are comparing peak ratings to peak ratings and continuous rating to continuous ratings.
SINGLE-PHASE VS. THREE-PHASE
Single- and three-phase auxiliary power are fundamentally different due to the design of the AC circuit. As a result, these two types of output cannot be directly compared. More importantly, jobsite tools may require one over the other. For example, most hand-held tools are single-phase, while many pumps, welders and plasma cutters require three-phase power. Furthermore, the available three-phase power will be higher than the available single-phase power.
Once again, be certain to compare available three-phase with three-phase, and single-phase with single-phase.
SIMULTANEOUS WELDING AND AUXILIARY POWER
Just like the weld output ratings, the auxiliary power ratings are the maximum output the machine can give you. These machines are designed to provide both auxiliary and weld output at the same time, but there is some give and take. The following table is an example of this.
As you can see, when you increase the weld output the available auxiliary power decreases, and vice versa. It is important to understand the needs of your jobsite and application before you buy or rent.
Finally, depending on the machine’s available auxiliary output, it is possible to run a second operator by plugging in an inverter-style welder to provide two arcs simultaneously. For example, a diesel-driven Vantage 549X can power a Flextec 350X PowerConnect inverter welder.
There are multiple engines available in the same amperage class. This is another important consideration in the buying process. Engine service networks can vary by location, so for maintenance reasons, you’ll want to consider an engine manufacturer that has a presence in your area. Also, you can streamline your maintenance operations by having the same engine manufacturer throughout your fleet: welders, lifts, tow motors, etc.
While all machines offer welding and auxiliary output, some machines offer additional functionality to maximize their versatility on the job site. Lincoln Electric offers engine-driven welders with integrated air compressors, hydraulic pumps and battery jump-start terminals. This can save space on your truck or job site, by combining multiple functions into one piece of equipment. Another great benefit is that you will not have to run cranes or tools off your truck engine, saving fuel and reducing wear and tear on the truck engine. It is especially useful in areas where vehicle engine idling is restricted.
With so many engine-driven welders available on the market, it’s easy to get overwhelmed. Remember to keep the process simple by focusing on the five primary considerations outlined above: fuel type, welding output/duty cycle, auxiliary power output, the engine manufacturer and additional functionality. Don’t be confused by product names that can sometimes be intentionally misleading. All the information you need can be found on the product specification sheet or owner’s manual. Just look over the documentation and buy what you need.