Is there a way to backup Dell Compellent volumes, directly i did hear a while ago that you could do this by copying/mounting the volume/snapshot to the backup server and backing it up from there, i think it is all powershell scripting but wouldnt knwo where to start.
Have a look at BE Admin Guide for info about off-host volume snapshots.
The link is for BE 20.0, but the BE16 Admin Guide should contain similar info.
To add to Marianne's info the HCL for BE 20.x does mention some Compellant Devices as supported (in the VSS Providers for Offhost backup section on Page 56)
You will need appropriate licensing in Backup Exec to use this (either ESO option with core product, Capacity or Gold)