Prevent the HDD from sleeping?

I have a new 3tb HDD (WD mybook 3TB) that i store my films on and use to stream via the PC to the TV.
I have found that even though its a powered hdd it sleeps , i have installed the WD drive utilities and turned off sleep after 30 minutes, but it says that it sleeps if not in use after 30 mins - if im streaming a film from the drive then the pc must be reading it so why does it sleep?
The PC does sleep during playback so will the external HDD still sleep because the PC does?
Playing the films from the PC internal harddrive doesnt get affected by the pc sleeping.

I don’t have an external HD like you but I do downloads that extend over multiple episodes and may take hours to complete. I do try to control the number of concurrent downloads to not affect the memory or the ethernet transfer speed.

What I have noticed is that even if the downloads are in-progress, the Computer Screen saver can get activated, thus putting the system in pause, which seems to terminate the download. I’ve gone into the PC control panel and changed the screen pause to 2hrs…that way I can at least be away from the keyboard or mouse. I believe that screen saver comes back on when you touch these 2 devices, and may not be controlled by what is being processed in the background. I remember years ago with the Win10 upgrade that took hours overnight…I read in a blog that you should by-pass the screen saver option…just a thought…Maybe others have a solution that’s better.

I don’t know why actual playing the video, even if done from the PC thru the TV would not activate the screen saver (if this is the cause) unless you are touching the keyboard or mouse. For my TV viewing, I transfer my files to a USB flash drive and plug it into a TV that can read USB movies like mk4, mkv or avi…less cables and setup of devices. Of course, streams won’t work for external USB unless you download the stream to an actual file.

Thanks for reply. When I speak of stream I am referring to “streaming” from the HDD through the pc and to the TV over the local network. I download the film and save it to the external drive as the pcs internal HDD is filling up. I use a programme called Ums to manage to transcoding or streaming to the TV.
I don’t have a screen saver but the pc does sleep after about 15 minutes and then goes into a deeper hibernation that requires a press of the keyboard instead of simply a wiggle of the mouse after another 15 minutes or so…

I see, you stream thru the PC directly into the TV…I think there is 2 types of sleep modes…one for the screen, and one for the PC. If you type Settings in to the lower right search box, then select System > Power&Sleep you should see sets of boxes where you can choose how long the screen stays up or how long the PC stay…If the laptop is got an external power, you don’t necessary want it to shutdown, especially for streaming. I had my PC set to never and the screen at 30min…I believe that if you move the keyboard or mouse, the screen stays on, but the PC never shuts down…give some like this a try and see if you can improve your viewing. I know people use this PC to TV for full family Zoom conference with family…I’m not there.

Since you store to an external HDD, maybe moving to a Flash and inserting the Flash into the TV would be less stress on the PC…of course, the TV needs USB’s that can read and convert for TV viewing…see if that even works for you.