Text Dr. Jörg Lantzsch ––– Photography
Wiring enclosures without a printed wiring plan? For decades, nobody at Schaltanlagenbau GmbH H. Westermann could have imagined such a thing. “It’s actually a strange state of affairs, since there are of course many down sides to a printed wiring plan,” says Heinz-Dieter Finke, Technology Director at Westermann. Take a shift change, for example – how far has the worker going off shift got with the job? Which connections still need to be made?
And what do all the handwritten scribbles on the plan mean? To avoid as many of these difficulties as possible in the future, the company recently started using a digital solution for enclosure wiring. It is being supported by the Fraunhofer Institute for Mechatronic Systems Design (IEM) and the German Federal Ministry for Economic Affairs and Energy. “As part of the Digital in NRW competence centre, we are on hand to support medium-sized companies with digitization,” explains Robert Joppen, a scientist at Fraunhofer IEM who is helping with the project at Schaltanlagenbau GmbH H. Westermann. As part of their work with the competence centre, Joppen and his colleagues develop bespoke solutions for implementing Industry 4.0. Digitization in switchgear engineering is just one of six implementation projects, and the successes achieved in these are to be used as templates for other companies in the sector.
From a manual workshop to an industrial company
Schaltanlagenbau GmbH H. Westermann in Minden, Germany, is typical of the many medium-sized companies that make up this sector. Established in 1983, the company employs around 70 members of staff at two sites. “We have reached a tipping point for moving from a manual workshop to an industrial company,” says Commercial Director Uwe Friedrichs. Its primary areas of activity are switchgear engineering, automation technology and cable processing.
“We have optimised our production systems by expanding the production areas,” explains Finke: “We’ve reorganised and restructured our sequences, so the digitization project fits in very well with our strategy.” Finke believes that digitization taps into interesting potential in this changing market.
The question that kicked off the project was: “What does Industry 4.0 mean for switchgear engineering?” In a first step, various companies in the sector were surveyed as part of a study to identify key trends. The entire process chain was examined, from project planning and work preparation through machining, component installation and wiring all the way to inspection and commissioning. “At around 50 per cent, wiring accounts for the largest proportion of the total outlay that goes into creating an enclosure,” points out Joppen. “As a result, it is also one of the biggest sources of potential in the company. “Naturally, this potential can only be harnessed by looking at the bigger picture for the company.”
That is why the implementation project focused on this subprocess as a part of the overall process chain. To support the rollout of the project, a committee was put together with representatives from Eplan, Phoenix Contact, Rittal, Wago and Weidmüller. The committee members brought with them expertise in components, software and processes for switchgear engineering and contributed their own practical experience to the project.
End-to-end data retention is essential
Another important requirement when seeking to drive forward digitization in switchgear engineering is to ensure end-to-end data retention. “It became clear early on in the project that there were a lot of continuity breaks,” says Joppen. One of the reasons for this is that, on many projects, the customers provide their own planning, and this often comes not as electrical planning in Eplan, but as a PDF wiring plan. That means data sometimes has to be captured all over again if the production process carried out by the switchgear engineers is to be digitized. “When we take care of the planning ourselves, we don’t have any of that extra outlay,” points out Finke. However, that only happens in about 25 percent of jobs.
As part of the implementation project, a demonstrator was developed for testing the use of paperless wiring. A switchgear system was constructed using typical components in an AE enclosure from Rittal. A scientific evaluation was conducted on the production process using this demonstrator as a basis. Various staff – a trained electrician, a trainee and an employee with basic training – wired the demonstrator as part of the study. Each of them had to complete the task once using the conventional method of printed wiring plans and once with the aid of Smart Wiring. The time spent on each individual step and the quality of the wiring was also documented. Furthermore, staff completed a questionnaire that reviewed their experience on a subjective basis.
“Wiring the components in an enclosure involves a lot of manual work. When we were assessing the current state of affairs, we identified ‘paperless’ production as a possible project,” explains Joppen. In the past, wiring plans had always been printed out and given to electricians as they worked on the wiring. Each connection would be ticked off in the wiring plan as it was made in order to document progress. There are several disadvantages to this classic approach. For example, markings and notes can vary from one person to the next. That means workers taking over from colleagues at a shift change, for example, often have to start off by deciphering their workmates’ scribbles. Moreover, a printed wiring plan is only ever a snapshot of the project at one particular point in time. Changes made after the wiring plan has been printed out are not included. Also, if electricians carry out the wiring differently to the way it is set out in the wiring plan, they only document this by marking it on the printed version.
To ensure data stays up to date throughout wiring work, staff must be able to access digital – and therefore always up-to-date – planning data. At the same time, digital wiring support can be a valuable tool for making work easier. “At first, it wasn’t clear whether we’d have to develop our own tablet-based solution as part of the project,” recalls Joppen. However, market research quickly turned up the Eplan Smart Wiring solution, which offers all the desired functionalities. The software shows all the individual connections that have to be wired on one tablet. Besides the start and end point for the wiring, the system also maps out the colour, cross-section, wire end preparation and connection point designations. If a virtual prototype has been created for the system in Eplan Pro Panel, the route for the wire or cable can also be depicted. What’s more, because the wiring plans are sent digitally to the workstation, changes to the project can be communicated in real time.
“Preliminary results from the evaluation showed a clear time saving in wiring, even though that wasn’t the primary focal point,” says Joppen, commenting on the study. The employee with basic training was actually only able to wire the enclosure when using the tablet. An improvement in quality due to the standardised approach is also to be expected. Moreover, it was striking that the staff adapted the Smart Wiring solution to their method of working. For example, they used the filters on the application to better plan their work packages, which was partly how they achieved the time savings.
Digitization has only just begun
The implementation project shows that digitization works very well for wiring in switchgear engineering. The next step is to roll out the process on an operational level and establish it as a standard process. However, that will certainly take some time. At least, that’s how Friedrichs sees it: “We’ll definitely make good progress in the next five years.” One of the main tasks is integrating the processes with customers to ensure complete continuity in terms of data retention. Joppen knows very well that this will not work in all cases or to the fullest extent: “There will always be a small proportion of projects that we have to complete using printed wiring plans.” As Directors of H. Westermann, Friedrichs and Finke want to use digitization to harness the potential in production.