Power Supplies

Has anyone come across a power supply - 400W or above that will work on a low voltage DC supply?

We are looking at a project in an environment where nothing over 50v is permitted. There is an excellent 12v supply - with very high current capability along with other voltages that could be used.

Laptops/notebooks are NOT suitable and the PC will need to be built with an appropriate supply.

Get a 12V DC to 240V 50Hz AC Inverter with adequate wattage! I am sure you may get this through the Amazon or other On-line Stores. One good point from Amazon is you may get some users' comments.

Good luck

In reply to a post by OCdragon:

Get a 12V DC to 240V 50Hz AC Inverter with adequate wattage! I am sure you may get this through the Amazon or other On-line Stores. One good point from Amazon is you may get some users' comments.

Good luck

And how will that solve the problem?

There are some here from a US supplier, so they do exist.

Those look interesting - just need to find a European importer.

Your Google searching actually achieved something! Mine didn't!

try
http://www.cartft.com/
also see
http://www.mini-box.com/M4-ATX?sc=8&category=981

(although only 250w, you may be able to use a separate one for ancillaries )

dont forget most lcd monitors run a high voltage for the backlights, - might need to specify led backlight

They are sorted - they are LED backlit and have a 12V input!

I think you might struggle to get 400W at 12v input. Is there a 48v rail?

If so this might do the trick.

Otherwise if 300W isn't enough have a look at this site which has units going up to 700W

If you're really stuck with 12v and could actually manage with a smaller power budget then there's a 160W pico-psu which runs on a 12v supply, plus the car pc psus which have already been mentioned.

And how will that solve the problem?

It won't - I suspect that OCdragon didn't notice that the problem wasn't to run a PC on a 12v input but to avoid anything > 50v

There's loads of 48v stuff as that's the standard telecoms DC rail (see my other post) is that any use?

Thanks - it has to be 12v as that is the only supply capable of providing the power required for the PCs. We've looked at low power PCs bu the disc and video capability required is pushes up the total power.

Not enough available power on the 48v supply.

I hope I did NOT mis-understood your problem! But you said: "There is an excellent 12v supply - with very high current capability along with other voltages that could be used".

I did realise that >50V is classified as "unsafe" voltatage in certain Standards for distribution purposes! However it doesn't stop you from distributing your adequately powered 12V DC to each of your power points and then use a "local" 12V DC to 240V AC power-inverter each to do the job for you. Of course there may be 1) several such power-inverters involved, which would increase your costs, depending on how many "local" power-points that may require 240V AC supplies, and 2) your TOTAL POWER 12V DC supply must be enough to supply all your local needs. However your key benefits would be NOT needing to modify any of your existing 240V AC powered equipment at all and should be expandable provided you have worked out your overall "power strategy" beforehand. It is your call though!

In reply to a post by OCdragon:

However it doesn't stop you from distributing your adequately powered 12V DC to each of your power points and then use a "local" 12V DC to 240V AC power-inverter each to do the job for you.

Erm... depending why the area is restricted, yes it does.

OK, what about this? 12v in and up to 500W

Thanks, found that one from one of your previous links too.

To fully comply with the 50V upper limit, would you have to get an inverter capable of being fitted WITHIN the PC Case?

Otherwise, having an EXTERNAL Inverter may be breaking the Rules!

With the power you want from a 12V input you need to bear in mind that you're asking quite a lot. *Some* of the unheard-of far eastern power supplies are of *very* poor quality, and would not be appropriate for use in an environment where safety matters (eg anywhere). Somewhere on Youtube there's a selection of videos of exploding inverters (rated only slightly higher than you're asking) for use with grid-tied photovoltaic setups.

That being said, let's do a John Major and go back to basics.

I'm thinking 12V is all that's usefully available to you, is that correct? (Why? Is it negotiable?)

I'm thinking that Windows is a requirement, is that correct? Otherwise you could do what the rest of the world does when it needs reasonable performance at low wattage and use one of the many off the shelf ARM/Linux boards at a fraction of the size and wattage of a Wintel PC setup?

When you say "video capability required", do you mean you are recording video (as well as outputting it), hence you need lots of disk space? And the video needs to be relatively uncompressed?

Sounds like you've already found the up to 450W synocean/heading stuff at [1] ? The manufacturer's website is at [2]. I bet they're not cheap (no prices published is often a bad sign).

If this doesn't get you an acceptable but readily available 12V-to-PC PSU, how about home brewing (if you can't buy) a relatively simple 12V to 48V DC to DC SMPSU (a chip, a few resistors and capacitors, maybe an inductor or two, and a design safety/reliability analysis given the power and circumstances involved) and feeding a commercial 48V-to-PC PSU off that? It's a bit round the houses, and will therefore likely increase size and cost and decrease efficiency and reliability vs a genuine 48V-in option, but there seem to be some obstacles in your way. If someone like Farnell(.co.uk) doesn't have a ready made suitable power 12V DC in 48V DC out box, they'll have the bits and the info, and it won't be all that complicated.

In passing, I'm puzzled by what kind of environment requires <50V but permits high current 12V. Anyone who's ever dropped a spanner, screwdriver, etc across a reasonable capacity 12V (a car battery will do) knows just how much fun a few hundred amps can be, even for a fraction of a second.

[1] http://www.headingonline.com/p-990-300w-500w-12v-4u-...

[2] http://www.synocean.com.au/powersupplies/index.html

Have a PC built using one of these 12v i7 motherboards......

http://www.boston.co.uk/reviews/2011/10/mini-itx-mot...