Alright after 13 years of service my CPU UPS failed me and i

>>1226758
pc power supplies don't have switches anymore between geographic regions, the switcher can adapt the duty to take input between something mad like 90-250v, probably a little outside that too comfortably.

i doubt they would care if it was a DDS wave, the only thing stopping it working on DC is the input transformer, smps doesn't give a fuck.

>>1226773
however the SMPS does give a fuck on undervoltage conditions (87v)

As far as i now it starts making noises and the transistor go nuts due to overcurrent compensating low voltages, shortening the life of all the components at once, and sometimes even killing the SMPS (has happened me at least twice)

>>1226778
Run the PC gear on a 220V dryer circuit then. Then voltage drop will only go as low as 174V which is still in range.

>>1226784
thats not an option, what im looking for is mostly a "undervoltage protection system"

All you need is a ups with double conversion. Then all your problems will go away.

I use 10kva to 50 kva units in industrial environments. We have crazy dirty power. But on the protected side of the ups I can set my watch to that sinewave no matter what the incoming transient.

Another way is you could just make a 48v battery bank with a rectifier. This is how I power some blade servers. It's quite a bit more efficient but you'll need an atx supply that accepts 48. Can be done with 24 and 12 as well but you mileage may vary.


Relying on what the utility will do and switching is a fools game for sensitive electronics no matter how good your atx supply or an offline ups is.

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>>1226787
I would gladly like you to expand more about this topic, i'm mostly an electronic engineer, i love the electrical side of things

Making a quick look on Double conversion UPS i found mostly rack units, i couldn't find a unit to place in the entrance of the electrical service (after the meter if possible) ideally it should be able to hold up to 3000w (30A 127v) however after exploring a bit Im not sure this is the right application for this kind of device, seems more like a direct replacement to the UPS that died plugged to my CPU


I know im asking for something really strange, but im lookling for a "resettable" way to shutdown my electrical system on undervoltages or overvoltages (just like a fuse would do on a short or a breaker by overheating or a GFCI by a ground fault)

>>1226758
Where the fuck do you live where voltage swings that large are common?

>>1226799
Mexico City, its kinda funny, in the last 8 years we never got over voltages nor power outages in but we did had these 3 under-voltages in the last couple years (only damage was a led lamp which i replaced the SMPS)

I installed an online monitoring system recently to keep track of all of this since im not always at home, the gaps with no lectures are me messing with the hardware

https://emoncms.org/app/view?name=myelectric&readkey=b31c43d353c05b0961091f0f15fd6d2e

>>1226801
>(only damage was a led lamp which i replaced the SMPS)
and probably the UPS, im really sure about this one not sure}

if i recall correctly a fridge also died like 4 years ago

>>1226798
>i'm mostly an electronic engineer,
>>1226785
>what im looking for is mostly a "undervoltage protection system"
solution seems pretty obvious...

>>1226801
Well damn, Anon, that sucks.

At the same time I'm more glad than ever that our grid only interfaces with yours in a small chunk of Baja California.

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>>1226806
To be fair the electrical grid was way too old (my home is 70 years old)

The electrical utility has been getting way better in the last years with state of the art upgrades but still there's stuff to be done all over the place

Also pic related is the voltage during a normal day (peaks are when the microwave is activated)

My cheap APC UPS definitely handles undervoltage. Sometime it even switches when my laser printer turns on. It's probably not sine though.

>>1226798
If you wanna do a whole panel with it look at the expensive commercial models such as Eaton powerware.

Plug in versions, even to 6000va are available rackmount and tower.

Here's a 3kva tower at 120

http://www.apc.com/shop/us/en/products/APC-Smart-UPS-SRT-3000VA-120V/P-SRT3000XLA

Honestly most of your house won't need this just the electronics. I run a 1500va apc one and it handles tv, pc, modem, router, etc. Just takes a 15amp plug and I'm practically at 30% load.

>shutdown electrical system

Self latching contactor for cheap uv protection

Or a contactor/breaker with a protection relay for enhanced protection.

I think it's just alot of hassle when you could just buy a good ups and forget about it for 5 years easy. It ain't any cheaper either unless u happen to have the parts lying around.

>>1226758
https://docs.wixstatic.com/ugd/1baea3_12ebbca5e2f24c25a3abb4827fb2558f.pdf

>>1226890
holy shit this shit is amazing

https://www.youtube.com/watch?v=qy7AZe5rUus

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>>1226758

cyberpower 1500 VA reporting in

>>1226944
holy fuck son, im glad im not a transistor i can almost feel the pain

>>1226931
Why u wanna cut the mains instead of backup power? That shit gonna fuck up your Fs

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>>1226758
>we do get undervoltages (87v) and most UPS do not protect against this

bullshit even cheaper UPS's can be adjusted thru software to compensate for voltage differences. even a standard off the shelf UPS will do this. pic related my APC UPS settings, these are the minimum settings too.

>>1227205
This, OP is an idiot.

>>1227205
>>1227230
This.