VDI VDI/VDE 3687 PDF

Purpose and scope

The expansion of automation activities has in recent years led to a tremendous increase in industrial information transmission and in the communication systems on the market.

A variety of problems faces managers in the search for assistance in selecting and deciding and project engineers, planners and operators in search of guideline assistance.

• Can the practitioner actually find his way through the multiplicity of communication systems?

• What are the most important bus systems for practical application in automation?

• What level has the associated international standardisation reached?

• Should the user wait for standards or would it be better to use existing industrial standards?

• What concepts should be used to deal with the following points?

– A disproportionate growth in data flow under real time conditions.

– Increasing decentralisation of automation functions.

– Growing pressure of business competition and the resulting drive towards new, networked automation concepts by the users.

• What criteria can be used to select a suiTable bus system for a user?

The use of this guideline provides a systematic procedure for evaluating and selecting a communication system for specific requirements. Using the guideline to achieve this requires the following procedure to be adopted.

Starting from the fields of application of industrial communication described in Clause 2.2, it is necessary to first properly establish the communications tasks to be met from the point of view of the user. These include the following.

• The planned number of communication nodes.

• The quantity, frequency and time sequence of the data to be transmitted.

• The operating conditions for the field bus system to be chosen.

• The economic efficiency of the use of a field bus system.

The following Clauses of the guideline can be used for this purpose.

• The introduction to the requirements of industrial communication in Clause 2.1.

• The requirements tables and examples for the various fields of application in Clause 2.2.

• A comprehensive selection check list in Clause 3.

• An explanation of terms and definitions in Clause 6.

• The overviews in Annex A.

This means that in a second step the user can to a considerable extent select the system suitable for him, using the Tables in Clause 5 which give the properties and data of open bus systems.