Electrical Slip Rings by DEUBLIN

December 15, 2021 4:51 pm

Electric slip rings enable the transmission of power and data currents from a stationary component to a rotating one, therefore they are often also called Electric rotary joints. Very often slip rings are used in rotary machines. These are used by fillers cappers and weighers of food, beverage, household products or pharmaceuticals, but also for packaging building materials such as cement or similar. Many other machines, such as labelling systems, are also suitable for these applications. Slip rings are increasingly important as rotary packaging machines and lines become more and more complex with regard to automation, process visualisation, analogue or digital sensor data, status conditions and power currents as well as system networking. In addition, two aspects increase the amount of data: On the one hand, the specifications for serialisation and traceability throughout the entire production process right into the supply chain. Secondly, the task of making the plants ready for Industrial IOT and Industry 4.0.

Therefore, higher data transfer rates at high bandwidths and the control of fast data protocols such as Ethernet are required. This can be achieved for existing packaging systems by upgrading with suitable slip rings or directly during the design of new packaging machines, systems, or entire lines. However, the solution to these tasks for the packaging sector is not simply the question of, “I‘ll just install a slip ring there“. The issue is far more complex than that. Different factors from the application are incorporated in order to find the suitable, high-quality and, above all, sustainable components: Influencing are e.g. the HF shielding, the processing of mixed signals, contact resistance as well as operating temperature, environmentconditions regarding IP protection class and vibration. And additionally, the transfer of other physical media, such as air or water,as well as restrictions in the installation space also play a major role. Electromagnetic interference (EMI) is one of the biggestchallenges with high bandwidth. Ethernet signals and current must be transmitted via the slip rings when they are networkedwith the Internet. These signals can react very sensitively to external electrical interference. Moreover, to maximise dataintegrity, the electrical brush noise must be considered – an index for the contact resistance of each electrical channel when theslip ring rotates. Brush noise, EMI and debris within the slip ring can all affect the quality of data signal transmission, measuredin lost packets per million, and this area of high-quality data transmission is where the new DEUBLIN product really excels.

DEUBLIN, manufacturer of conventional rotating unions as well as slip rings, contributes 70 years of experience to the task and presents its latest range of products – the SRC and SRD series as solution. While SRD offers a specified channel assignment on the flange and higher standardisation, which means that many applications can already be realised in the packaging segment, the SRC series is based on the modular, customisable basic structure, which enables variable channel numbers and through bores. Both series can transmit digital and analogue signals in both rotational directions with up to 100 Mbit using DEUBLIN contact technology. The IP65 protected housing allows installation in vertical or horizontal position and even in contaminated environments. Comprehensive options such as heating resistance against condensation at low temperatures, anti-rotation devices, plug & play connections as well as plugs, flanges or cable ends, which can be customised, allow adaptations for applications in the packaging sector.

Of course, there are also differences in the slip ring series: Depending on the model, the maximum number of rings for the SRD series is 32 or 66 depending on frame size. The SRC series, on the other hand, has a maximum extension of 99 rings. Depending on the configuration of the ring and brushes, currents of 1-60 A per ring are possible. The products are based on components of proven and qualified construction blocks as well as advanced HF and EMI techniques in order to guarantee high data integrity. For the product line of slip ring transmitters DEUBLIN applies the same principles as for the classic rotating union: Highest quality and 100 percent tested before a unit is used in practice. No matter whether it is a pure slip ring or a combination with a conventional rotating union, it is always advisable to consult with experts on this subject and to seek advice in order to establish future-oriented solutions.