Summary (English):
It is one of a series produced to facilitate the interconnection of automation system components. It is related to other standards in the set as defined by the "three-layer" fieldbus reference model described in IEC/TR 61158 1. This sub-part contains material specific to Type 3 fieldbus. It includes the following significant changes with respect to the previous edition deletion of the former Type 6 fieldbus, and the placeholder for a Type 5 fieldbus data-link layer, for lack of market relevance; addition of new types of fieldbuses; division of this part into multiple parts numbered.
