CAEX (Computer Aided Engineering Exchange ) is a neutral data format for storing hierarchical object information. The original intention for the development of CAEX was the lack of a uniform and imported data exchange format among the disciplines of process and process control planning. Means CAEX For example, the hierarchical system structure to be imaged, which insists on a certain level of abstraction coupled and parameterized modules and components. CAEX allows you to store these modules and components using the object approach. It explicitly supports concepts such as encapsulation, classes, class libraries, instances, instance hierarchies, inheritance, relations, attributes and interfaces. CAEX based on XML and is an XML schema defines ( xsd file).

CAEX can be used for technical static object structures such as system topologies, document or product topologies or Petri nets. However CAEX can also be applied in the non-technical area, eg for storing pedigrees.

Technical Details

CAEX modeling techniques combined with meta-modeling techniques. The modeling techniques allow storage of object information that is compatible across manufacturers, including objects, attributes, interfaces, hierarchies, references, libraries and classes. The meta- modeling techniques, however, allow a flexible definition of those object information, which is usually dependent on the manufacturer, for example, certain attribute names, specific classes and object catalogs. CAEX mainly serves as a storage object static information and is not originally intended for the storage of dynamics. However, it is possible to define a class library for the description of dynamic behavior descriptions to use for example process description languages.


The CAEX development began in 2002 as a university cooperation project between the Department of Process Control Engineering, RWTH Aachen under the supervision of Prof. U. Epple with industrial support of the ABB Research Center Ladenburg. In 2003, the first CAEX proposal in the German standardization committee DKE ( K941, TC65, WG12 ) was presented. In 2004, CAEX has been proposed as part of the DIN V 44366. After a positive international Voting CAEX was published in May 2005 as part of the IEC PAS 62424. In 2007, in several different workshops suggestions for CAEX collected and consolidated and incorporated into the IEC 62424 CDV as CAEX version 2. After another positive vote, the international IEC 62424 CDV ( Committee Draft for Voting ) is available.


CAEX currently serves as CAEX version 2 ( version 2.15 ) is available.

Development partners

CAEX 941 was developed within the DKE K together with industrial companies such as Bayer, BASF, Linde, Uhde, Wacker, Intergraph, Siemens Industry Solutions, ABB and the RWTH Aachen.


CAEX is currently being researched and used in the fields of process planning, control planning, the oil and gas industry and in the manufacturing automation. The data format for storing AutomationML plant design data includes an implementation of CAEX.

The following research institutes contact CAEX and explore its potentials ( as of 2007):

  • RWTH Aachen
  • HSU Hamburg
  • TU Dresden
  • Fraunhofer Institute for Information and Data Processing ( IITB )
  • Imperial College London