Can someone definitively say for sure that I can just use two independent PSUs? One for GPUs and one for GPUs and motherboard and SATA? No additional hardware?
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.
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.
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.