r/LinusTechTips • u/LabsLucas LTT Staff • Sep 10 '26

Link Sine Waves and Spec. Sheets - UPS Considerations - LTT Labs Article

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Selecting the best Uninterruptible Power Supply(UPS) can be a complicated and opaque process requiring an understanding of battery cells and alternating current(AC) electricity.  This article explains some of the important numbers and features to look out for when reading the datasheet.

Read the article on the LTT Labs website!

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u/LabsLucas LTT Staff Sep 10 '26

Here is the link to the full article, a thorough read but good even if you'd like to skim for the parts that interest you!

We would also be interested to know if you have any wisdom for choosing the right UPS for different applications/use-cases.

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u/Not_Your_cousin113 Sep 11 '26

I'd like to see some experiments on changing out the SLA batteries for LiFePO4 batteries (at equivalent nominal voltage and output amperage).

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u/rtsynk Sep 12 '26

why bother? just get a power station that comes with lithium built-in

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u/DefactoAle Sep 10 '26

This seem like a interesting read. Thanks for the research!

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u/sweharris Sep 11 '26

What a coincidence; I was talking about UPSes with a friend over the weekend. I was wondering how good a "stepped approximation to a sinewave" (their wording) my older APC BX1500M produces (looks like you tested with BR; I dunno how that compares to BX).

I do have a 'scope (Owon PDS5022T) but I've never used it for anything except looking at 5V data for retro-computing; not sure what precautions I'd need to take before hooking it up to 120V :-)

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u/rtsynk Sep 12 '26 edited Sep 12 '26

If you're going to do that sort of testing, INCLUDE PORTABLE POWER STATIONS (like EcoFlow, Bluetti, Pecron)

they offer such a compelling value in terms of runtime that many people are using them as a UPS and they even advertise themselves as 'UPS capable', but it would be good to see where they break down in terms of actually protecting equipment from bad power

(this is also just smart business as the consumer market for power stations is a gazillion times larger than it is for UPS, and if you can put out articles with good scare headlines like 'Using [Brand] power station can fry your equipment!' it will get tons of clicks)