CpmPlusKMOpcHdaServer files > 110GB
Yes. You can delete those log files. Also, you may have to delete these log files from the Essential Backup (Example: BackupDrive:\EssentialBackup\WeekDay4\diag\OpcServer).
Generally, the file size doesn't grow much. If possible could you share one of the log files with me firstname.lastname@example.org. Please provide the DCN History software version by running rtdb_version from CMD prompt.