The Vehicle Electric Container (VEC) is a standardized data model that facilitates the exchange, collaboration, and archiving of electrical network, wiring harness and wiring harness component information in the automotive industry. It serves as a tool-independent digital representation of a vehicle's electrical system, supporting the conceptualization and design of logical mockups, the exchange of component data or the product specification of wiring harnesses. The VEC helps ensure traceability throughout the lifecycle of a vehicle's electrical system.

Developed under the guidance of the VDA and the prostep ivip Association, VEC is a standard in the automotive industry, and is published as VDA 4968 and PSI21.

Note: The complete VEC standard can be found here: https://ecad-wiki.prostep.org/specifications/vec/

This Companion Specification utilizes subsets of the VEC data model for the description of 'Article' and 'Part' information (see Figure 2). There are multiple reasons for this:

1. It enhances interoperability and consistency in the exchange of data across different systems and equipment within the automotive industry. Article and Part information is used throughout the process, not only in communication with production machines.
2. Components for the wiring harness (Parts) and the wiring harness itself (Article) are diverse, with great variety and many facets. Reusing vetted modelling concepts for their description increases the quality of these aspects for this Companion Specification and enables accelerated and efficient definitions.
3. It allows this Companion Specification to focus on the additional aspects that are relevant to machine communication, such as job management, result data and process parameters.

Due to its scope as a common language in the wiring harness value chain, the VEC standard includes modelling concepts that are necessary in the design and engineering process, but not during production or for certain machine types (e.g., system schematics). The data model elements used in this Companion Specification are a subset of the complete data model defined by the VEC standard.

Concrete mapping between VEC and OPC UA is described in section 9.

Figure 2 – VEC as Part of the Job Description

The key concepts of the VEC are DocumentVersion and 7:PartVersion (see Figure 3).

Figure 3 – Basic Structure of VEC Data

A 7:PartVersion in VEC is a unique identifier for a specific version/revision of a part. In VEC terms, a part is essentially anything that is used in the product or is created during production (a part can be composed of instances of other parts). This means that a 7:PartVersion in VEC applies to both the Part and Article in terms of this Companion Specification.

Note: A Part represents a type definition, not a specific instance of a Part; in other words, a Part is identified by a part or material number, not a serial number.

The term DocumentVersion goes back to the roots of VEC in the STEP standard and the document-oriented product development that prevailed at that time. In fact, DocumentVersion in the VEC stands for any piece of information or a data set that is clearly identifiable and whose changes can be tracked (e.g., a certain state of the properties of a connector, a terminal or a wire [Parts in this Companion Specification], or the definition of a lead set [Article in this Companion Specification]).

The content of a DocmentVersion is used to describe 7:PartVersions. They are represented by individual entities for the following reasons:

1. In general, a document can describe multiple parts at same time, whereas a part can also be described by multiple documents (e.g., a data sheet, a drawing, a 3D model).
2. Both can evolve independently, so tracking of changes & revisions must also be tracked inidividually (e.g., the data for a component can change without changing the physical component).

For example, in the context of this Companion Specification, this could mean that if a machine is sent a new 7:PartVersion, the input material has changed physically and the machine needs to be re-equipped for this new material. However, if only the content of a DocumentVersion changes, the same material processed, just in a different way.

The 7:PartVersion and DocumentVersion is a generic concept for tracking hardware and information changes. The information is described using specific subtypes of Specifications within a DocumentVersion.

Every subset of the VEC model that defines a specific aspect of the product has its own Specification; for example, a connector is described by a ConnectorHousingSpecification, a terminal by TerminalSpecification, etc. The same applies for more complex aspects of the article definition; e.g., the bill of materials is defined with a PartStructureSpecification, the contacting of wire ends with terminals with a ContactingSpecification, the basic structure of a wiring harness or leadset by a TopologySpecification, the geometric form by a BuildingBlockSpecification3D, etc.