For a bit more than a century, low-voltage switchgear has been developed and manufactured at Eaton. If you compare today's devices like the motor-protective circuit-breaker PKE including electronic wide-range overload protection with the universal contactors initially produced, a great deal has happened particularly in the last 30 to 40 years. Today Eaton uses the intelligent communication system SmartWire-DT to connect its switchgear components to integrated automation solutions in the context of a Lean Solution strategy. The next development step is currently the Industry 4.0-enabled solutions based on smart devices.
It all started in 1912 with 1-pole and 3-pole universal contactors and 3-pole miniature oil contactors from the development center of Moeller in Bonn. Twenty years later, the first motor-protective circuit-breaker PKZ of today's Moeller series was developed. The short name PKZ now not only stands for high quality but is sometimes used in professional circles as a general synonym for motor-protective circuit-breaker. With the PKE with electrical wide-range overload protection put on the market in 1999, Eaton is systematically continuing this long tradition of innovation in the the area of motor-protective circuit-breakers.
Since the first oil contactors were developed more than a hundred years ago, only a few employees at Eaton can remember them. These simple models were then followed some 25 years later by the first air contactor. Although auxiliary contactors were predicted to soon be completely replaced by semiconductor switching elements already 40 years ago, the universal contactors - both the smaller auxiliary contactors and the more powerful power contactors - maintain their market position up until today due to their special advantages.
Even today, in old installations there are still functioning air contactors that were produced 40 to 50 years ago. The contactors made by Moeller, forerunner of today's Moeller series, were advertised since 1930 with a machine service life of 30 years, for example. Today, however, shorter and shorter modernization intervals of automated machines are determining the required service life and quality of the switchgear. That's because nowadays very few machines can be used competitively after 30 years. However, the switching frequencies with modern machines are often significantly higher than in the past, and the necessary motor power is constantly increasing. Modern contacts normally switch in the medium of air or arc-free with larger amperages (e.g., > 580 A) and with a substantially increased service life in gas-tight vacuum interrupters.
Intelligence gets a foothold
The next major development step was the introduction of motor-protective circuit-breakers with electronic wide-range overload protection such as the PKE. In the 65 A current range, this now represents an intelligent alternative to the proven bi-metal solution of the PKZ. Both models are part of the product range Xstart for standard components for the motor starter assembly. This range includes auxiliary switches and releases, connection technology, and DIL power contactors. They are all perfectly matched, are considered "standard" devices which are easily replaced, and can be easily combined into motor starter combinations.
Thanks to its compact and modular design with plug-in contact blocks, the PKE from Eaton offers maximum flexibility. The innovative switchgear provides detailed operational and diagnostic information that cannot be transmitted via conventional control wiring. This means the PKE can report not only digital signals for switching or sensing switch positions or overload Information, but also analog values such as actual motor currents. This extended diagnostic information enables predictive maintenance (condition monitoring) - as part of the Intelligent Motor Control Center IMCC for the xEnergy control cabinet line, for example. This gives the system operator the ability to quickly identify fault situations and take measures to improve the operational reliability and minimize downtime time of machines.
This is made possible only through the connection of Eaton switchgear such as the PKE to the intelligent SmartWire-DT communication system as part of the holistic Lean Solution approach. Using smart Wire-DT, the complex and error-prone point-to-point control wiring of components such as switchgear, sensors, and actuators can be replaced with the central control system. Since the technology combines the data line and power supply, it also allows for uniform communication among participants - a basic requirement for the development of distributed intelligence in switchgear. The fact that all SmartWire-DT participants can be connected directly via the green wire with simple plug connectors enables a significant reduction in the cost of wiring, testing, and commissioning. But the further development of switchgear doesn't stop here.
Smart devices as the foundation for the Factory 4.0
Currently, manufacturers of automation components are being challenged to develop intelligent solutions that allow businesses to network their entire production into a "smart factory." This requires smart components (smart devices) in machines that can communicate with all the processes as well as with other machines and components, robots, ERPs, logistics programs, and people. And this is precisely where Eaton comes in, extending its proven Lean Solution strategy to include smart devices. This means that as an overarching framework, the Lean Solution strategy compiles simple components and smart devices into integrated systems on each machine of a production line.
In order to increase the efficiency and sustainability of production processes, design engineers are increasingly relying on decentralized, networked automation concepts. Eaton takes this trend into account and is successively integrating further automation components into its intelligent communication system SmartWire-DT. As the example of the PKE shows, in this way the motor-protective circuit-breaker at Eaton has developed over the last hundred years from a simple oil contactor into a communication-enabled smart device as part of intelligent, networked automation solutions.