The Lincoln Electric Co., Cleveland, Ohio, has unveiled its latest multipurpose, engine driven welder/generator, the Commander 500. The welder features Lincoln's newly developed Chopper Technology, which is designed to control the d.c. welding output to create an arc with increased welding performance. In addition, the Commander 500 welder/generator is engineered to deliver exceptional stick, TIG, cored wire, MIG, and arc gouging performance, the company said.

"What our engineers did was basically take a typical chopper circuit and adapt it to specific welding applications," said Eric Snyder, product manager for engine driven welders at Lincoln Electric. "The Chopper Technology works like a simplified inverter, which are starting to become very popular within the welding industry.

"We're taking three-phase power and putting it through our specially designed chopper module. At the heart of this module lies an integrated gate bipolar transistor or IGBT, which takes this three-phase a.c. and rectifies it to d.c."

At this point, Snyder explained, the chopper module operates like a high-speed switch by turning on and off 20,000 times per second. "So it's basically turning your output on and off, let's say between zero and 100 amps. That is so fast, that as far as the welding arc is concerned, it just looks like a solid d.c. line - just a straight line right at the 100 amp level."

"The high-speed switch circuit provides a great deal of flexibility to address all the welding processes. The result is easy starts, smooth arc, good bead appearance and lower splatter levels on the welded piece."

The Commander 500 welder/generator provides 500 amps of welding power at 100 percent duty cycle, and is suited to the construction, maintenance, repair, rental and pipe industries. Besides being a d.c. multi-purpose welding machine, it is also designed to generate 12 kW of a.c. power from the 120 V/240 V full-kVA receptacle or 4.8 kW of a.c. power from two 120 V duplex receptacles.

A single, full-range control dial for stick and CV-wire applications is equipped to control general welding output. The unit features five ranges with full overlap for stick pipe welding and other processes where slope control is required.

The unit is powered by a 2.8 L Deutz F3L912 industrial diesel engine rated 44 hp at 1800 rpm. This three-cylinder, four-cycle, air-cooled diesel features 12 V electric start, a Donaldson two-stage dry-type air cleaner, Stanadyne fuel filter with water separator and a custom-designed Lincoln muffler.

Indicator lights displaying low oil pressure, high oil temperature, broken cooling blower belt and low engine alternator voltage are supplied by Faria and Prime. An engine protection system is designed to automatically shut down in the event of a broken blower belt, low oil pressure or high engine temperature. A 25 gal. fuel tank minimizes the need for frequent refueling, Lincoln said.

The Commander 500 welder/generator series includes the standard Lincoln K1639-1 and deluxe K1639-2 model alternators, both driven directly off the engine. The deluxe model includes dual digital output meters for presetting weld amps or voltage and the display of actual outputs during the welding process.

The deluxe model also has Prime and Faria engine gauges for fuel, temperature, oil pressure, broken coolant blower belt, and low engine alternator voltage. Both units have a six-pin connector for remote output and a 14-pin connector for use with other Lincoln wire feeders. The deluxe model also incorporates a 30-minute delay low-fuel shutdown.