What power supplies are made for "mission critical" applications

[gevorg]

What kind of specs do these power supplies need to achieve?

Just wondering how consumer/prosumer power supplies differ from the ones that are used in professional/scientific use.

 

[Modelworks]

Most of the requirements in healthcare will be of high isolation. You don't want voltage passed to a patient in any way. If you are in any hospital you will always see a label on equipment that states when it was last checked for safety. They do Hipot test.

http://en.wikipedia.org/wiki/Hipot


Some consumer supplies come tested but the cheaper supplies do not. If it has been tested it will usually say hipot tested. A lot of hospital supplies use transformers on the input that provide 1:1 isolation from the wall.
Professional supplies also have very accurate regulation. They use voltage reference sources. Basically circuits with only one function, to provide a voltage that is fed into a circuit that adjust the output voltage. It does not provide the voltage that the users connect to. It is only used as something to compare the output. For lab work 12vdc accuracy is usually from 11.997 to 12.003 whereas a pc it is 11.400 to 12.600 . So a big difference.

The other thing is ripple. Think of ripple like the waves on water. Every dip is a change in flow. For PC supplies ripple can be 5 -10 mV for lab work .001 mV

Lastly is the monitoring circuits that watch the output , if it deviates for even a 1/10th of a second the monitoring circuit trips.

 

[Bull Dog]

Pretty much everything that had potentially deadly amounts of voltage in it has to be hipot tested. Even the really cheap POS PSU's that I've seen were still HiPot tested

 

[PM650]

I think a lot of what the extra cost goes into is the design & testing process, and maybe a few tens of percent into better/more parts. Specifically regarding power supplies, linear types are a joke to design (audiophoolery crowd & associated equip. aside), all the money goes into SMPS design - where a lot of factors are in play; lots of bench testing & analysis work to figure out why the output of a PCF-boost converter is ringing at 10MHz or looses regulation under load, for example. Sure a piece of scientific equipment will achieve tighter specs, but imho the real work goes into torture testing & verification that it isn't going to fail randomly or after a relatively short period of use, and designing based on proven solutions, rather than what's easiest.

Just as a real example, take some of Denon's recent AVRs (2008-9 & probably 2010). Several higher-end models are having problems with their HDMI boards failing - I can't assume this is true for all cases, but all of them that I've repaired have been one thing - a failed switching IC (EN5312QI) used as a down-converter for 3.3V -> 1.2V/1.3V. The IC is a completely monolithic power supply - all that is necessary for implementing it is the typical input/output filtering capacitors, and a simple voltage divider (2 resistors) to set the output voltage. The catch (or point of interest) is the IC has an integrated inductor, which works out great for the designer using it. This type of integration will spur further innovation into what we can stuff onto an IC, but the problem is it isn't nearly as robust as a discrete solution - you won't be seeing one of those chips sent up on a piece of satellite hardware any time soon. In the end, this is just what you can expect from the vast majority of mass-produced items, in some form or another. No shortage of dead LCD monitors even today from bad capacitors, produced by cap manufacturers who have been making garbage for years...

 

[ChaiBabbaChai]

For pro audio and CGI/VFX - whatever is in the Mac Pro 😛

Scientific - depends on the project, but custom multi-CPU systems like the Roadrunner or maybe just a dual-CPU workstation.

I have heard, from people in the field, a little about scientific computers, but I've personally been in major recording studios and visual effects studios where they just have stock Mac Pros with add-on cards.

 

[Modelworks]

Originally posted by: Bull Dog
Pretty much everything that had potentially deadly amounts of voltage in it has to be hipot tested. Even the really cheap POS PSU's that I've seen were still HiPot tested

The difference is in hospitals it is done every 6 months to a year for the equipment to remain in use. It is usually a yellow or green sticker with a date of test and the signature of the person who passed it.

 

[herm0016]

the power for digital audo is not too big a deal, but for analog audio applications you will find huge torrid transformers and very good voltage and noise control.

 

[Rubycon]

For pro audio (amplification) high current and efficiency are chief movers.

How about 20kW in a 1U size?

http://www.k-series.it/

:Q

 

[ChaiBabbaChai]

This is a computer forum... I thought we were talking about computer power supplies. :Q

 

[JEDIYoda]

Originally posted by: ChaiBabbaChai
For pro audio and CGI/VFX - whatever is in the Mac Pro 😛

Scientific - depends on the project, but custom multi-CPU systems like the Roadrunner or maybe just a dual-CPU workstation.

I have heard, from people in the field, a little about scientific computers, but I've personally been in major recording studios and visual effects studios where they just have stock Mac Pros with add-on cards.

Pro audio is not mission critical...rofl

 

[Rubycon]

Originally posted by: JEDIYoda

Pro audio is not mission critical...rofl

Yes it can be. A gig is a mission and if your gear goes belly up in the middle of a performance you're done!
In the studio it's very expensive to have sessions ruined by malfunctioning gear as well. While it would not be a disaster like a live performance it would add costs to production costs.

 

[ChaiBabbaChai]

Originally posted by: JEDIYoda

Originally posted by: ChaiBabbaChai
For pro audio and CGI/VFX - whatever is in the Mac Pro 😛

Scientific - depends on the project, but custom multi-CPU systems like the Roadrunner or maybe just a dual-CPU workstation.

I have heard, from people in the field, a little about scientific computers, but I've personally been in major recording studios and visual effects studios where they just have stock Mac Pros with add-on cards.

Pro audio is not mission critical...rofl

LOLERSKATES... That's debatable, and I'm sure you'd lose that debate, but read the OP's sub-topic. You never know what people are thinking (wrong word choice, reader comprehension level, naivety, etc.)

 

[tcsenter]

Originally posted by: gevorg
Just wondering how consumer/prosumer power supplies differ from the ones that are used in professional/scientific use.

Redundancy. That's pretty much it.

 

[faxon]

one of the things for pro audio (assuming you mean professional audio work and audiophile grade listening) is having the cleanest power available to power your stuff. i just had my X-Fi completely shorted a ton of capacitors that were unneeded on my X-fi after replacing the primary analog driving capacitor with something much more powerful (it's a well documented mod), and i swapped the $15 AC>DC supply for my headphone amp to one 5x larger with multiple filter caps and a VRM prefilter stage for each cap. it made a big difference in the quality of sound output on my system when listening to high quality recording playback. the sound is much warmer and more natural, the bass is more punchy, and there is less distortion when using higher driving currents on low playback volume pieces to compensate.