Hacker News

Top stories

Live mirror
30 storiesupdated just nowView source snapshot
  1. Laya the open source version of Jev(convaiinnovations.com ↗)
    120comments
  2. A graphical desktop for the ZX Spectrum(github.com/mindbox77 ↗)
    37comments
  3. Tin: full-text search for Postgres(planetscale.com ↗)
    21comments
  4. AI-generated posters don’t have to be horrible(john.hartnup.uk ↗)
    426comments
  5. Human brain is two separate organs, Stanford Medicine-led research finds(stanford.edu ↗)
    176comments
  6. Black Holes or Black Hole Stars? Astronomers Spar over 'Little Red Dots'(quantamagazine.org ↗)
    11comments
  7. “The Secret Life of Circuits” is here(coredump.cx ↗)
    48comments
  8. What Zig felt like, coming from Rust(besok.github.io ↗)
    93comments
  9. Android 17 is the first since 3.x to add new APIs without releasing to the AOSP(grapheneos.social ↗)
    541comments
  10. I built the fastest PHP webserver in the world(qbixserver.com ↗)
    14comments
  11. Asking Authors About Their Own Papers(medium.com/tmlrorg ↗)
    28comments
  12. Jobs Without LeetCode(noleet.lol ↗)
    discuss
  13. Agreement between the USA and Denmark (1951,2004) [pdf](state.gov ↗)
    1comments
  14. San Francisco Onion Futures Company(onionfutures.com ↗)
    105comments
  15. GPT-6 Astra Solves a WWI German Radio Cipher(prinzai.com ↗)
    126comments
  16. If math is more than proof, we need to better celebrate the rest of it(terrytao.wordpress.com ↗)
    186comments
  17. Learning Another Language May Be One of the Best Ways to Keep Your Brain Healthy(theconversation.com ↗)
    33comments
  18. Cloudflare Quick Tunnels(cloudflare.com ↗)
    301comments
  19. How to Write with an LLM(sockpuppet.org ↗)
    360comments
  20. You can run Git on object storage if you re-make packfiles(tigrisdata.com ↗)
    23comments
  21. Communication by means of modulated Johnson noise(pnas.org ↗)
    18comments
  22. Saving another 100TB of RAM(cloudflare.com ↗)
    89comments
  23. Ray Ozzie and the Optimism of Being Early(reproof.app ↗)
    9comments
  24. SDCC – Small Device C Compiler(sourceforge.net ↗)
    23comments
  25. Science Is Open Software(jepedersen.dk ↗)
    49comments
  26. From Stonemasons to Carpenters(thelastsoftwareengineer.substack.com ↗)
    4comments
  27. Why building a Rust LSP is hard(rust-glancer.github.io ↗)
    44comments
  28. The first new cat species discovered in 100 years(nationalgeographic.com ↗)
    122comments
  29. OpenJev(openjev.com ↗)
    278comments
  30. Ctenophores: Wonders of Biology(quantamagazine.org ↗)
    7comments

Ask HN: What's a good electrical UPS for a home dialysis machine?

3 pointsby 2y ago
7 comments
I'm asking here as well since there's a higher concentration of electrical engineers who would know these things.

I've been desperately searching for a good and affordable UPS solution for a home dialysis machine for my father in law (FIL). There's been several power outages due to storms where he lives and he's lost all blood in the machine on one occassion.

I've created a reddit post [1] as well with more details. But to summarize we're looking for a UPS solution with a power rating greater than 2000VA that can last upto 90 minutes. So far we've settled on APC SmartUPS products since they provide a 4ms switching time which I expect to be a good. The products cost around $4000.

Any additional info would be much appreciated! Any better UPS out there more suitable for medical equipment? Any cheaper UPS units other there with the similar quality to APC?

[1] https://www.reddit.com/r/dialysis/comments/1dztvgk/nxstage_system_one_electrical_power_outage_ups/

2y agoHN ↗

Not an expert, but...

What does the manufacturer of the dialysis machine recommend? (Either specific brands/models, or generalities about the quality of power needed by their machines.)

In many areas, "power failure, and resident needs power for a home medical device" is a situation that the local Fire Dept. / EMS / Utility regularly handles, or has protocols for. I'd check with them. If nothing else, if things really went sideways and they were responding to your FIL's home, having a UPS that they were familiar with could be a real benefit.

2y agoHN ↗

Just got back a reply from the manufacturer that they cannot recommend any UPS. They clarified the specs the UPS should have which is 1200VA + sine wave + 120V.

2y agoHN ↗

D*mn! ...but 100% understandable, from a liability PoV.

Though I might still be tempted to ask them if they could anti-recommend any UPS's. Saying that they heard of someone using a FooBar X2400, but it didn't end well, could still be useful. Especially if you'd tentatively decided on a FooBar X2400.

2y agoHN ↗

You might want to look into EcoFlow. I use their River system to provide backup power for my home equipment (I have frequent power outages, usually about 2 hours in length). I can't tell you whether it'll work for medical equipment, though.

2y agoHN ↗

I checked out EcoFlow a few weeks ago along with the Anker Solix range. Anker's switching times are around 20ms and I wasn't able to find EcoFlow's switching times. The switching times indicate the UPS performance. It needs to be quite low for sensitive equipments like a dialysis machines. The APC SMX range provides switching times of 4ms.

2y agoHN ↗

UPDATE:

The requirements have been brought down to 1200VA so the APC SMX2000LV (2000VA) seems to be a good choice for UPS. It's much cheaper on Amazon too.

There's a company called mediproducts that offer UPS units for medical equipment but their pricing is opaque at the moment.

Ideally I'd love to chain an affordable battery backup solution like EcoFlow or Anker Solix along with a good APC UPS. But I'm concerned about chaining two sine wave generators (they become sine wave generators when there's a power outage). But I have no clue if that causes any cascading issues or not.

2y agoHN ↗

Have you considered hiring a local electrical engineer of the sort that works on buildings?

I mention this because your loved one might be better served by an actual design rather than generic suggestions and construction rather than shopping. I mean this is kind of life and death. Good luck.