Hey everyone! For my home server and PC I have a UPS to protect against power outages. To my utter shock, I recently discovered that it draws around 50 W * idle (meaning with the device turned on, but nothing connected to it), which is also reflected in the unit becoming quite warm to the touch. I found this to be an obscene amount and have since been doing some research.
The UPS I got is a APC Smart-UPS 700VA 230V. I acquired it in used condition from a friend and haven’t changed the battery. I don’t know how old the batteries are, but according to the manual , the device has been manufactured between 1995 and 2000 and the typical battery life is 3 to 6 years. I don’t know whether the batteries have ever been changed, but I suspect not.
Per the website my unit is a line-interactive UPS and the fact that it starts buzzing when I interrupt the power seems to confirm that. However, what I found out on the internet suggests that line-interactive UPSs shouldn’t have such high power draws at idle, which confuses me. Personally, I would blame this on the age of the device and battery. What do you think?
I am not willing to accept this high of a power draw for a device that most of the time just does nothing. I mean I would totally get it with an online UPS, but we’re talking line-interactive here. So I hope someone could share some experiences regarding the idle draw of more modern offline or line-interactive UPSs. Are they as bad? How do offline and line-interactive compare in idle power consumption? Because for a potential new buy I would like to keep the benefits of line-interactive like surge protection and over- and undervoltage compensation.
* that is, assuming my power meter actually measures effective power and not apparent power.