[ilovecurl]

Anyone remember Rackable Systems Inc.? Their selling point was all about reducing data center costs by doing all the DC conversion in these massive converters at the top of the cage. They supplied something like 48v down rails in the back of the cage that their servers would then plug into via special connectors on the back of each server. They promised more efficient power conversion and better thermal management amongst other things.

I was never comfortable working with/around that stuff. I was always worried about a mishap that could bring me (or the cage itself) into contact with 48v of pure DC doom.

[adamsb6]

This is how the big cloud vendors do, see OCP server and rack designs for an example. IIRC the rack connects to one leg of a three phase and converts to DC inside the rack’s UPS.

It’s great for efficiency, but makes a hassle bringing in third party equipment since you need to make accommodations for bringing in the regular AC power that everything else is designed for.

[mrguyorama]

48v DC is just under OSHA's opinion of what you should start being careful with. The heat generated by a short could easily burn you though.

[yummypaint]

That is plenty to weld with if the current is available. Even a 12 V car battery is serious business.

[threadweaver34]

I was looking into getting a UPS for my server. Some UPSes do power conditioning, and all do AC/DC conversion. I got to wondering why I can't buy a UPS that outputs DC and feed that directly into a silly looking PSU.

[Scoundreller]

Was their game plan going to be that their power supplies were more efficient than those traditionally in rackmount servers?