A cev file extension is related to the SEL compressed event report format. Probably obsolete.
CEV file extension - SEL compressed event report
What is cev file? How to open cev files?
File type specification:
The cev file extension is associated with the compressed event report format developed by Schweitzer Engineering Laboratories.
Most likely some old format without support. No further information could be found.
This cev file type entry was marked as obsolete and no longer supported file format.
This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.