What is the file extension for a Studio 5000 project?

The file extension for a Studio 5000 project is ACD. This file type represents an Automation Control Designer project file, which is the primary file format used when working with Allen-Bradley’s Studio 5000 software. This extension indicates that the file contains detailed information about the project, including configuration data, ladder logic, function blocks, and other programming elements essential for the operation of Allen-Bradley PLCs.

In terms of the context of the other file types, PLN typically refers to a project plan in different software contexts, STP is often associated with STEP files used in CAD applications, and PJT might suggest project files in other software but is not related to Studio 5000. Thus, ACD is specifically tied to the functionality and structure of projects created within the Studio 5000 environment, making it the correct answer.