Hi, I had a cheap UPS (or "USV" as it's called in German) once. It came in a plastic case and worked fine for a long time.
Until it went crazy and didn't charge anymore. It continued beeping until the battery was drained. However, it never damaged my stuff.
Personally, I think that an UPS is a fine piece of equipment, if it's a quality model.
A good one in a big metalcase with screws can house high-capacity lead-gel batteries that are long-lived but also can be replaced if necessary..
If you use vintage gear, also make sure the UPS has a serial port.
It can be used to automatically shut down the PC, but also used for diagnostics (battery status, inverter status etc).
From what I remember, Windows NT 3.51/4.00 had UPS support built-in..
Anyway, I would consider keeping the existing filters and protective circuits in place. They shouldn't harm and may help to reduce stress for UPS/PC..
PS: Sorry for my poor English.
Some sentences went out badly,
but I don't know how else to properly express what I want say. 😅
Exit: Lead-gel batteries are more user-friendly than lead-acid batteries, from what I know.
The gel type doesn't "gas out" (right English term?) , doesn't leak and is less sensitive to wrong orientation.
Edit: https://simple.wikipedia.org/wiki/Sealed_lead_acid_battery
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