External drives · Speed, cables and hardware
Can I stop my external hard drive from going to sleep?
Short answer: Partly. On Macs that offer it, turn off "Put hard disks to sleep when possible" in Energy (or Battery → Options) settings. Many drives also sleep by themselves, which only the maker's software can change. An SSD avoids spin-up delays altogether.
Partly. On Macs that offer it, System Settings → Energy (or Battery → Options on laptops) has Put hard disks to sleep when possible — turning it off asks macOS not to spin drives down. Many drives also have their own power-saving built in, which only the maker's tools can change.
A sleeping disk just takes a few seconds to spin up when you open something. If those delays bother you, an SSD avoids them entirely — see delays when opening files from a hard disk.