What can be improved in a product such as an enclosure that appears to be technologically mature? Where can we start? What does switchgear manufacturing need? The developers at Rittal asked themselves these questions five years ago. As the term 'Industry 4.0' had only been on the market for a year at the time, one thing was clear: the large enclosure had to be 100% Industry 4.0-capable. Because only the combination of a real enclosure and its digital twin would be able to meet all digitalization requirements in the future, from online configuration and engineering to assembly, automation and maintenance. "The new reality" is what Dr. Thomas Steffen, Managing Director Research and Development at Rittal, calls the merging of real and physical workflows in the product life cycle: "Without consistent, end-to-end data or software-based control knowledge, even an enclosure is not fit for the future."

Field research in the workshops

The company did not start the search for a future-proof enclosure system on the drawing board or in the laboratory - the motto was "back to the roots". "Before we allowed our team to develop the control cabinet, we had to go into our customers' workshops to completely reassess and analyze the current challenges," says Dr. Steffen. Together with the Munich-based institute PMO Usability-Engineering & Organizational Development, the system provider for control cabinets initiated a field study: the researchers documented everyday industrial life at ten companies in Germany, eight in the USA and six in China - including small, medium-sized and large companies.

Everyone who works with the enclosure product in the respective company was observed and interviewed. The documentation was written, partly photographed and filmed. However, the focus was not only on the enclosure installer, but also on a large number of user groups - including designers, logistics staff, installers, wire fitters, testers, commissioning engineers and maintenance staff. Added to this were the purchasing decision-makers - technical buyers, managing directors and asset managers. The usability study therefore went far beyond what is understood today by 'user experience' - it included tasks and context.

"The user analysis was an eye-opener. In some cases, we identified problems for the customer that they hadn't even noticed themselves," summarizes Dr. Steffen. 150 specific requirements for the new enclosure emerged, which Rittal supplemented with the findings of the customer advisory board, which was also involved. After the usability study, any remaining doubts about the strategic direction of the large enclosure to be developed were dispelled: "The market needs an enclosure that immediately shortens throughput times in engineering and assembly, reduces complexity in view of batch size 1 and fits in with the digitalization megatrend as a fully-fledged building block," says Dr Steffen. To summarize: Enclosure construction must become more digital, simpler and faster.

Three development teams

Before the design implementation of this guideline, however, there was an intermediate step in which three development teams were 'sent into the race' at the same time: the Research and Development team at the Herborn headquarters, a team from the Rittershausen plant and an assembled team from an external development service provider, which was supported by two 'veterans' of the enclosure supplier as consultants. These three teams were tasked with designing the profile for the enclosure of the future without any contact between them. The teams were familiar with the findings of the field study, but worked completely independently without any design restrictions. In October 2013, two profile designs from each of the three teams - over 200 in total - were presented to the 'jury', consisting of the owner Dr. Friedhelm Loh and the Managing Director of Research and Development, Dr. Thomas Steffen. The main selection criteria were the functions and customer benefits.

Focus on customer benefits

The result is the 'VX25' enclosure, in which the manufacturer has only focused on those areas where it offers customers an advantage. "We have retained the tried and tested features as far as possible in order to make the changeover easier for our customers," explains Matthias Müller, Head of Product Management Enclosures. What is new is that "the control cabinet ticks in the same way as the customer thinks and acts: in terms of functions and processes".

One example is accessibility from all four sides. This means that the outer assembly level can be fitted from the outside, which in practice makes life much easier for a good 40% of Rittal customers. In this way, around 30 minutes can be saved compared to conventional assembly.

A consistent 25 mm dimensional grid and symmetry help to reduce the complexity of control cabinet technology.

© Rittal

The same applies to the option of installing mounting plates - especially heavy ones - from the rear. In addition, an extra 20 mm installation depth at the rear offers more room for maneuver. This is important in order to meet the demand for higher packing densities.

Furthermore, the flat parts of the 'VX25' are provided with a unique QR code to optimize the value chain of customers, whereby the components are assigned to the respective parts list item in the customer's merchandise management system. This allows, for example, the flat parts to be tracked throughout the entire workflow, assigned to the correct processing programs and their processing times recorded. Multifunctional components also reduce the complexity of the variety of parts.

Assembly without tools

The cabinet accessories can be installed in the plinth, which combines the functions of the 'TS' plinth and the 'Flex-Block' plinth system.

© Rittal

Thanks to the snap-on handle system, time is also saved when changing the handle, which is now twice as quick as before. Whereas previously the handle had to be fitted with screws, now all you have to do is "hold it once, press it shut, done". The previously necessary gluing of the baying seal is also no longer necessary with the new cabinet, as it is now plugged in. A screw connection in the baying direction simplifies any combination on all sides.

Further simplifications relate to the door: in future, customers will no longer need to machine the door for 180° hinge installation. Previously, it took around 30 minutes per door to convert a door to 180° by drilling eight holes, deburring and then painting. Today, the door can be hung and unhooked like a front door and is automatically secured when closed.

Another innovation is the switch cabinet base. It combines all the functions of the predecessor plinth (TS) and the 'Flex-Block' plinth system. The enclosure accessories can be installed in the base. Cables routed in the base can be
and fixed via system chassis. Last but not least, an integrated centering aid in the corner piece simplifies positioning and the plinth can be attached directly from above.

Authors:
Ulrich Kläsener is a journalist at Mediabridges in Bergisch Gladbach;
Hans-Robert Koch is Group Manager Product Communication at Rittal in Herborn.

Control cabinet construction 4.0

Real and physical workflows merge thanks to high data quality and consistency in engineering.

© Rittal

Control and switchgear manufacturers who want to align their productivity with Industry 4.0 need all data in maximum quality throughout - from electrical planning to mechanical design and production. With complete data for all processes along their value chain, the 'VX25' large enclosure system supports control and switchgear manufacturers in this. Rittal provides various web-based software tools for the changeover to the enclosure system:

With the 'VX25 conversion aid', parts lists from the previous 'TS 8' enclosure system can be converted into VX25 parts lists. Parts lists from projects that are to be reused only need to be loaded into the conversion tool as an Excel file using drag & drop. Once the columns for article number and quantity have been selected in Excel, the user receives the desired VX25 parts list with a single click. Items without VX25 relevance are automatically displayed in the list. The translated parts list can then be downloaded or added directly to the shopping cart for online ordering.

In addition, plant engineers receive support when converting from 'TS 8'-based 3D enclosure layouts to VX25 system technology in 'Eplan Pro Panel' projects. The replacement of old control cabinets and accessories with new items is largely automated.

Support for the plant manufacturer

Further support for the changeover is available via the free download of detailed, validated CAD data in over 70 formats for flexible data transfer to all common CAD systems. The 'Eplan Data Portal' can also be used to load macros of the VX25 bayed enclosure system for mechatronic engineering using CAE/CAD and the creation of 3D enclosure layouts with 'Eplan Pro Panel'. There is also data for classification according to eClass (Advanced) and ETIM.

VX25 Selector' enables the selection of enclosures and suitable accessories. An error-free, 'plausibility-checked' configuration - even without CAD knowledge - of the enclosure system and the desired expansion components is made possible by a web-based configurator. As the configured data package contains a CNC program for the Perforex machining center and a 3D step model of the complete enclosure including accessories in addition to the parts list, mechanical processing can also be planned with the 'Rittal Configuration System'. In this way, the enclosure data flows directly into the machining processes.