A Descriptor can also be used to share the product information of AutomationComponents building a product family. By a product family, one usually understands a range of similar products that have a set of common features but are distinct in certain aspects, like size and performance. There is no clear rule either on how small or big the common feature part is or on how many individual products a product family contains. A product family may also be split into subfamilies.

Drives are an example of a product family, as seen in Figure 12. The drives have the same basic features and a similar look and feel. The product dimensions, power, voltage, and other drive features will vary within the family, but the general structure, operation and application are the same.

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Figure 12 – A drives product family

There are two examples of designing product family information with Descriptors.

Each member of a product family or subfamily is described by its own Descriptor with product information. All these Descriptors are embedded in a new Descriptor for the product family, and the Root AML Files of the embedded Descriptors become Root AML Files of this new Descriptor. This is shown in Figure 13.

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Figure 13 – Example of a Descriptor for a product family using embedded Descriptors

However, this approach leads to duplication of the common part of the family data. Therefore, another example of creating a Descriptor for a product family is to combine the common part data into one OPC UA FX Information Model file and create one file for each product family member with the individual features, e.g., product identification data and distinct capabilities. This can be done either by adding the features to the common part or changing (overriding) a common part (default) feature. This is shown in Figure 14.

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Figure 14 – Example of a Descriptor for a product family with common data part