To put the system to sleep, set up a user script with the following set to run at a certain time
#!/bin/bash
echo -n mem >/sys/power/state
The drive spun up/down status however might be incorrect, so it would be wise to run this script before putting the system to sleep: https://forums.unraid.net/topic/103621-spin-up-script-not-working-since-update-69/page/2/?tab=comments#comment-963255