Question about "high" running temperatures

Hello,

I own several 2TB Easystore external drives, and I routinely run extended tests using Hard Disk Sentinel/Data Lifeguard to verify that things are running smooth (everything’s 100% okay). The tests usually take around 4 hours to complete, and for about 2½ of those hours my drives usually reach 48°C before cooling off near the end (for reference, when I first connect them to my PC they’re usually hovering around 24°C), which has me wondering: how long can these drives sustain high temps before it actually becomes a problem?

I mean, unless I’m completely wrong, I don’t imagine 48°C or so for a little over 2 hours is that much of an issue. Am I right in assuming that temps would have to be a bit higher for a few hours longer before any real damage is done? I apologize if it’s a stupid question, but it’s quite difficult to find a somewhat definitive answer on what kind of temps I should avoid (and for how long). For example, I have a few 5TB Easystore drives as well and, as you can probably imagine, extended tests usually take even longer with those…I’m talking around 48°C or so for several hours. Surely these things are built with that in mind?