SMD disks were first using 11" platters, later 8"; and with a nominal speed of 3600 rpm, thus 60 rotations per second (although Fujitsu later deviated from the norm and had a few drives spinning even faster, at 3961rpm), it took a noticeable amount of power to spin these disks up (and a smaller one to keep them spinning, which one would notice when receiving the bill from the electricity company).
I wouldn't mind having a few of these to act as backup flywheel batteries. Maybe if civilization crashes these will make a comeback as dual use power & data storage devices. ;)
I worked on replacing some PLCs a number of years ago that used drives like these and used the energy from the spin down when power was lost to write anything important to a short 8-track like infinite tape loop, gracefully-ish shutdown, and send messages to the monitoring gear.
Comments
I wouldn't mind having a few of these to act as backup flywheel batteries. Maybe if civilization crashes these will make a comeback as dual use power & data storage devices. ;)
I worked on replacing some PLCs a number of years ago that used drives like these and used the energy from the spin down when power was lost to write anything important to a short 8-track like infinite tape loop, gracefully-ish shutdown, and send messages to the monitoring gear.