Power without contact

The world of automation continues to innovate and adopt technologies that can have a positive impact on reducing down time and reducing costs. In line with the fourth industrial revolution, Industry 4.0, and the Internet of Things (IoT), now we see the development of truly contactless power transmission which can eliminate the need for human intervention for recharging systems, thus creating solutions where critical cleanliness and efficiency are required. The development of intelligent power transmission solutions is just one of the key steps along the road to the smart factory.

In cleanroom applications, keeping products and processes absolutely clean and preventing contamination are decisive factors. To this end, the work area needs to be encapsulated as far as possible so that neither dust nor dirt can get in. Whilst plug-in connections can cause particulate contamination, contactless power transmission enables clean connections which can even be routed through a glass wall. This also applies through plastic, cardboard and liquids – as long as the material in the air gap is not metallic or magnetic, then the transmission works perfectly.

Contactless power transmission is something we’re all familiar with. Take electric toothbrushes, for example. This transmission method means that the brushes are charged independent of a plug-in connection that’s subject to wear. Industrial applications benefit enormously from this level of flexibility.

In industrial automation, electrical power is usually transmitted via plug-in connectors, but with this conventional solution, burned out, warped and dirty contacts are a common cause of time-consuming and costly production downtimes. This is especially true of applications with frequent plugging cycles. With a contactless system, the power transmission operates without wear or maintenance, increases plant availability, reduces service calls and ensures that maintenance costs are practically eliminated.

This innovative system uses inductive resonance coupling to transmit up to 240 watts of power – voltage: 24 volts DC / current: 10 amps – without contact over an air gap of up to 5mm at an

efficiency rate of up to 90%. With the FreeCon Contactless system from Weidmuller, this is currently the only system on the market that can be switched directly via a PLC without using an additional contactor.

FreeCon Contactless works by generating a magnetic field on the primary side by means of a coil. The receiver also consists of a coil, in which a voltage is induced by the magnetic field. When an electrical load is connected to the coil, current begins to flow and electric power is transmitted. To cope with the increased heat produced by this transmission technique, Weidmuller has come up with an innovative thermal management system which keeps the temperature within manageable limits whilst allowing the system to have a compact design.

Each half of the FreeCon transmission system measures just 100mm x 100mm, with a height of 47mm. The housings of this system have an ingress protection class of IP 65 and come with flexible mounting options – direct mounting or mounting bracket – which allows it to be used in many applications.

The clever technology of contactless power transmission opens up entirely new possibilities of making a connection. For example, the primary and secondary sides can be brought together from any direction and power can even be transmitted whilst the elements are rotating! The accurate coupling the system takes place via a precise position control called ‘advanced pairing’. Previously inconceivable applications are now possible because a connection can be made by automatically bringing the two elements together.

Think of the applications this could be used for: In an automatic transport system, the driverless units would move to their charging station independently just before the battery goes flat or at the end of the working day, thus eliminating the need for human intervention for plug-in connections.

Or how about the need for an interchangeable tool on robots? The automotive industry makes use of applications that require frequent plugging cycles, such as industrial robots performing tool changes. The robots work with a variety of tools, which they independently change for different tasks, such as gripping or welding.

The high level of wear on the mechanical plug-in connections can be avoided entirely with a contactless system. This saves both time and money in terms of contact maintenance and replacement, in addition to minimising machine failures caused by maintenance work or defects.

Manufacturing is in the midst of a whole new era of technology that is transforming the systems and processes of the modern factory. It is the companies that grasp this and recognise how it can

improve productivity in their own plants that will be in a strong position to maintain an edge over their competitors. At a time of rapid change, organisations need to consider which technological investments will have the biggest positive impact on their business.

Press room


The Olden Group

Marketing communication for technical industries


The Olden Group

21 High Street


Devon, EX31 1BG


01271 375393