Size of incremental backups

Hi!

I have a Windows Server 2012 R2 machine running BE2014.1. I have a backup-set of some files on that server and 2 VMs. On Sunday a full backup is running and from Monday till Friday an Incremental Backup.

The fullbackup is about 280 GB, the last incremental backup was 30 GB. But if I look to my backup drive there will be only backup-sets with 280 GB, the incremental too! But on the elapsed time of the incremental backup there will be only 30 GB be copied. After the backup the catalog with 280 GB will be created.

Any idea?

Greetings Michael