In many companies within the European Union, machines are not used in isolation, but as part of an integrated system - they are therefore interlinked. The depth of this interlinking varies and each brings with it specific legal requirements, the exact definition of which often remains unclear in practice. In this context, people often talk about "interlinked machines". Many of these systems often do not meet the legal requirements of the Product Safety Act (ProdSG). The reason is often that the manufacturers or operators do not understand the differences in the types of interlinking and are unsure of the legal obligations that arise from this.
Definition of a machine according to the European Machinery Directive 2006/42/EC:
- A machine must contain at least two moving parts that move relative to each other.
- They use an external energy source.
- They serve a specific purpose.
Machinery generally requires a CE marking. For interlinked machines, the definitions and rules are less clear. The question arises as to who is responsible for placing interlinked machines on the market and how the term "complete machine" is defined. According to the directive, a complete machine comprises several linked machines, but in practice this provides little clarity. The distinction between minimal interlinking and deep interlinking can be a good way to make a decision:
Minor chaining
The minimal linking means that individual machines are connected but continue to function autonomously and can easily be separated from the network. Each machine in the network meets the definition of a machine and all normative requirements; bears a CE mark; is technically decoupled and can be productive independently after separation with little effort (for example via manual loading or similar).
Deep connections
In contrast, a deep link means that the individual machines can only function as a whole. There are no individual control units; the entire system is controlled centrally. With a deep link, the individual machines become a new overall machine. This overall machine requires its own CE marking.
Distinguishing between these types of chaining and understanding the associated legal requirements are crucial to avoid security deficiencies and comply with legal requirements. This article aims to help eliminate the uncertainty that often exists and to provide clarity in the application of the legal framework.
