[SOLVED] Does an 'offline' HDD still spin?

[JorgeIcarus]

Hello everyone.
I have 2x 4TB HDDs. One is a mirror of the other, I run an automated mirroring backup once a week. I keep it "offline" in Windows 10.
Now, CrystalDiskInfo shows that the PowerOn count and hours of the 2 HDDs is actually the same?
I thought that keeping the disk "offline" would prevent wear and tear, but apparently I was wrong.
Any ideas on how I could "switch off" the backup HDD and hopefully prolong its life?
Thanks

HDD1 (always online)

HDD2 (backup, almost always offline)

 

[popatim]

Power to it = powered up. You might wish to install the drive into 5.25" drive bay adapter where you can install the drive when needed
Example: https://www.amazon.com/StarTech-com-5-25-Hard-Drive-Swap/dp/B073JJ2FVR

or put int in a usb3 enclosure
example: https://www.amazon.com/Mediasonic-ProBox-K32-SU3-Drive-Enclosure/dp/B0065DUJ0C

or in a drive dock
example: https://www.amazon.com/Sabrent-Estación-acoplamiento-disco-externo/dp/B0759567JT

 

[fzabkar]

Try revoSleep:
https://www.meinfach.net/revosleep/

BTW, notice that the "Head Flying Hours" are considerably lower for the offline drive.

 

[JorgeIcarus]

Thank you both.
I am trying RevoSleep.