Using Libraries is highly recommended due to the productivity gain they bring. Some advantages of ElipseXs are the following:

•Reusing source code

•Reducing tests during development

•Creating default interfaces for developed objects

•Reducing development time for new projects

•Protecting project's content

•Ranking objects

Thus, using Libraries is recommended for most applications. However, there are some criteria to indicate the need to build objects in E3:

•Repetition of use: If the same device or process is used more than once in the same project

•User knowledgeable procedures: Often, a process created by a specific company must be protected against copies or changes. This is common in case of service integrators or machine manufacturers

•Use of controllers: A process controller, whose memory mapping is fixed, can be implemented with all available functionality. The available flexibility for building and using objects in E3 allows that only variables of interest are used later, ignoring the other ones