Three decades of inverters in welding - started by Kemppi
Kemppi Oy celebrates an anniversary this year, as 30 years have passed since Kemppi introduced on the market the world's first multi-process inverter power source. The new technology brought to welding more versatility and light weight, but it also had a favourable effect on the environment.
Almost exactly three decades ago there was a revolution in arc welding equipment technology which resulted in significant enhancements to usability and features.
That was when the world's first welding power source to use inverter technology was introduced on the market. It was none other than the Kemppi Hilarc 250, which was launched at an Essen Welding Fair in 1977.
Inverters brought light weight and versatility to welding
Today, the welding inverter is a familiar concept to anyone working in or knowing about the welding industry. However, there are probably many who do not fully understand the impact that inverter technology actually had on arc welding equipment, much less what is precisely meant by ‘inverter technology’.
In simple terms, inverter technology involves conversion of the voltage frequency in alternating current coming from the mains power. This allows the power source properties to be controlled in a variety of ways.
The introduction of inverter technology made it possible to manufacture lighter but more effective and versatile arc welding equipment. Today's small but effective "giants of welding" or the versatile welding units used in pulse arc welding would not be worth manufacturing without the benefits of inverter technology.
It also improved equipment controllability and made it possible for a single welding power source to be used for several different welding processes: MMA, MIG/MAG and TIG welding.
Kemppi showed the way in the inverter research
Even though inverter technology has been known since the beginning of the 1900s, finding a way to utilise it in welding power sources was not easy. It was not until the development of components in the 1960s and 1970s that new innovations became possible, also in arc welding technology.
In Kemppi’s history, the 1970s were a time of intensive expansion and rapid product research and development. The company expanded its international operations and in 1967 opened a large administrative and production facility in the district of Okeroinen in Lahti, Finland.
In the 1970s, Kemppi was a world-leader in applying inverter technology to arc welding equipment and commercialising welding inverters. New technologies were not actually developed in inverter R&D, but existing methods were used in a way that allowed for the release of an entirely new welding power source on the market.
The research lasted for nearly the entire decade. The R&D team developed prototypes and finally completed work on the first welding inverter suitable for commercial production and serial manufacture for introduction at the Essen Welding Fair in 1977.
Inverters lightened the environmental load
Inverter technology brought various benefits to the welding comfort and productivity. Besides to this, it has had one effect, whose importance has been growing along the years, and that is the reduction of environmental load.
We can say that the introduction of inverter power source was an act that can be considered truly environmentally friendly. Especially in MMA welding the energy consumption of welding power sources shrank significantly with the inverters.
For example in the contemporary Minarc MMA machines the idle power consumption is one third smaller than in Kemppi's earlier generation Mineka power sources of the same capacity, which were based on the old rectifier technology.
The difference in energy consumption between inverter power sources and conventional power sources can be still much greater. This means that the favourable effect of inverter technology to environment is significant, even though the share of MMA welding has decreased during the years
