Glad to hear things are working correctly
The detection of actual disk parameters (including health, temperature and so) works like an other read command for the hard disk, so it resets the idle timer.
If the idle timeout is set to a higher value, it is possible that Hard Disk Sentinel polls the drive more frequently, preventing the drive(s) from sleeping.
In contrast, if Hard Disk Sentinel detects that a drive is actually sleeping, it does not try to poll information, to prevent wake up of the corresponding drive(s). In this case, the last measured information is still displayed, but on the Information page you can see that the drive is sleeping (Power state: sleeping, not active).
Please check Configuration -> Advanced options, where you can adjust the frequency of the detection. Just set it to poll information once per every 30 minutes or every hour (or even use less frequent setting) according the power management setting of Windows.
This is true for all versions, no difference between the standard/Pro/Enterprise versions.