Hi all, What is UPS input load and how can that affect the power draw of devices plugged into it?
Context: I have an Eaton UPS. Into it I plugged TP Link smart plug to measure how much my homelab draws (1 truenas server, 1 rpi and a switch). These draw about ~29 W when under low to medium load. Almost every day (different time) for couple of hours, however, the plug measure about 6-7 Watts more (~36 W). I have checked both linux devices and they were doing basically nothing. Then I looked into TrueNAS monitoring and noticed that the start and end of each event is exactly the same time when UPS input load is increased from 0 % to ~6 %.
What is this UPS input load and how is it possible it affects measurements by a device that is plugged into it (the UPS) - NOT the other way around? Thank you
It’s weird to do this daily, but it’s possible that the UPS is doing a self test, which would drain the battery a little and the load is from charging it back up.
Same as above. The TP link that measure the power is plugged into the UPS not the other way around. The UPS is directly in the wall plug. So even if the UPS drawn 100 Watts it shouldn’t show on the TP Link.
Ahh sorry, I thought you meant you plugged it into the input side. If that’s the case then are you running anything that measures CPU usage? I run the TIG stack, it might be able to give you some hits. Also back to my original point which is already unlikely, if it’s a modified sinewave UPS, it can confuse some measuring devices while it’s on battery.