When powering on or power cycle, it takes a long time to load the SCU option ROM screen when there are drives connected to the SCU ports.
This is normal behavior. The SCU option ROM brings all drives online and look for metadata in the drives. The SCU option ROM assumes there is metadata in all the drives, and the larger capacity the drive is the longer it takes to scan for this metadata. This results in long SCU option ROM screen load up time.