Completed REVOCCASES RCC-BRICKMOD500 / build your own power brick with up to 500W output

REVOCCASES

Shrink Ray Wielder
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While looking for some 12VDC alternative to the HDplex 400 AC-DC PSU I came up with the idea to develop a (cooling) case kit for the quite popular MEANWELL RPS-400, RPS-500, EPP-400 and EPP-500 power supplies. As you might know, they can deliver up to 400/500W if cooled sufficiently.

With this kit you can build your own small external brick with up to 500W output power.

So here is the plan for the final product:
  • black anodized aluminum case for improved passive cooling,
  • 106x55x158mm (WxHxL)
  • compatible AC-DC PSUs: RPS-400C, RPS-500C, EPP-400C and EPP-500C
  • support for one 40x10mm fan internal or thicker 40mm fans external
  • fan speed / temperature controller included (fan stays off under light load)
  • standard C6 AC connector for ease of use / safety
  • TBD: DC output connector, cable set
Compatible DC-DC ATX Power Supplies:
  • G-Unique Archdemon (DC 12V)
  • HDPLEX DC-DC (DC 16-30V)
  • ... etc ...
Prototype:



Build Video:

 
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troybot

Average Stuffer
Sep 6, 2018
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Forgive the ignorant question, but does this still need an external brick?
As for comments, would it be better to have a slim 80mm fan on the larger side and not the tiny 40mm fans? That would mean better airflow for less noise. Or possibly even 60mm
 

REVOCCASES

Shrink Ray Wielder
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Forgive the ignorant question, but does this still need an external brick?
As for comments, would it be better to have a slim 80mm fan on the larger side and not the tiny 40mm fans? That would mean better airflow for less noise. Or possibly even 60mm

Are you familiar with HDplex power supplies? This is similar. You'll always have a AC-DC part and a DC-DC part. This is for the AC-DC part. If you mount it inside or outside depends on the case and if you have enough space.

Yeah, that is also an option. Therefore I'm collecting feedback what people would prefer. Longer or taller unit.
 
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troybot

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Sep 6, 2018
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Are you familiar with HDplex power supplies? You'll always have a AC-DC part and a DC-DC part. This is the AC-DC part. If you mount it inside or outside depends on the case and if you have enough space.

Yeah, that is also an option. Therefore I'm collecting feedback what people would prefer. Longer or taller unit.
Thanks for the reply. Not at all, I'm more familiar with SFX supplies. But I did some googling and now I understand, basically there is a second piece as you said. Cool project though, good luck with it
 
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robbee

King of Cable Management
n3rdware
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At this size, aren't you basically building a flex atx psu without dc-atx conversion? Perhaps you could consider also making one for the 200W version, that would be perfect for APU builds and even smaller than flex.
 

Stainless_eel

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I've spent a bunch of time researching this. I use a pair of EPP-400-36 in an audio amplifier, and other than the low-load whine they work pretty great.

If we take look at the RPS-500-c datasheet (same as the EPP-500 but medical approved), we see an airflow diagram provided. 25CFM directed at side, looks to be a 70mm to 80mm fan 15mm thick, in a push configuration. The top fan version is offset, and does not mention a CFM, but it show a pull configuration. The enclosed with 40mm fan has it pulling through the primary side and offset 10mm from the PCB. Noctua 40mm have an airflow of 5.3CFM, 60mm have an airflow of 17CFM, 80mm have an airflow of 31CFM. Noctua 80mm can do it, but would need to be tested. The Meanwell RPS-500 test report lists burn-in temperatures at 320 watts/45c ambient, and It looks like your main area of concern will be the transformer (where all the airflow is directed in the diagrams) plus several of the switching mosfets. It does not look like the backplate cools the underside of the PCB with thermal pads to components but I don't have one on hand to confirm. You might gain from adding heatsinks onto the existing heatsinks, but they must be isolated with thermal pads. These do have OTP, so you should be safe doing airflow tests in a hot case.

A top mount 15mm thick fan on the RPS-500c will bring you to 58mm. On the RPP/EPP 500 it's 56mm, and on the EPP-400 it's 50mm plus stand-offs. going with side mounted 15mm gets you to 90mm wide, plus adding height if using greater than 40mm fans. Either way is still less than an SFX PSU, but it starts to get close.

Is this for 12V only systems? If using one of the 12v DC-ATX adapters, how do you plan on getting around the power limits on those? I was thinking of grabbing a picopsu and then feeding the the GPU/CPU power connectors through relays timed from the motherboard PS-ON signal. This leaves the meanwell always-on. My other idea was to build out the logic to make the mean well PS-ON compatible with motherboards and add a pair of SIP DC-DC converter modules (20$ish each for 15-20A from mouser). I'd need to doublecheck the ATX timing spec to make sure this will work.

There are a couple parts about this PSU that take it out of ATX spec. Its ripple is 200mv, test report shows 187mv at full load. PS-ON is inverted, and PS-good may trip early (though under full load the report shows 118ms, which is within spec). hold up time is short at 220v but fine with 115v. It also need to be run class 1 to hit consumer EMI class B spec (grounded through standoff's to a metal enclosure).

Personally, I think the big advantage of these guys is the 1RU height. In my mind the perfect way to set this up is by making sure there is case airflow, add some small heatsinks to the heatsinks, and building out the support circuitry to the side, making the overall size a little bigger than a 120mm fan (double thickness). My guess is with a little case airflow most systems that pull 300w on load should be just fine. If need more, you should be able to tie two of them together in parallel and always on and use the pico + relay setup for CPU/GPU cables. That would let you run passive and give you some headroom for running in a hot case. Size would end up 127 x 151 x 41 plus relays.
 

REVOCCASES

Shrink Ray Wielder
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At this size, aren't you basically building a flex atx psu without dc-atx conversion? Perhaps you could consider also making one for the 200W version, that would be perfect for APU builds and even smaller than flex.

I agree with you. A flex PSU has similar dimensions but it doesn't give you the option to use it optional as external brick.

I know many people dont´t like external PSUs but from my point of view this just makes most sense because it will free up space in the case for more important things... like that:



Of course I can also work on a version for the RPS-200 if there should be enough interest. :cool:
 
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REVOCCASES

Shrink Ray Wielder
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Thanks for your detailed feedback. Much appreciated.

You might gain from adding heatsinks onto the existing heatsinks, but they must be isolated with thermal pads. These do have OTP, so you should be safe doing airflow tests in a hot case.

Yes, thats the idea. The extruded aluminum case shall act as a large heatsink using thermal pads between the small meanwell heat sinks and the case. The small fan(s) shall help with cooling under higher loads. That won`t be enough to get 400/500W continuously but I hope for at least 85% load cont.

Is this for 12V only systems? If using one of the 12v DC-ATX adapters, how do you plan on getting around the power limits on those? I was thinking of grabbing a picopsu and then feeding the the GPU/CPU power connectors through relays timed from the motherboard PS-ON signal. This leaves the meanwell always-on. My other idea was to build out the logic to make the mean well PS-ON compatible with motherboards and add a pair of SIP DC-DC converter modules (20$ish each for 15-20A from mouser). I'd need to doublecheck the ATX timing spec to make sure this will work.

Would also work for 19VDC plug in PSUs. But I´m mostly thinking to combine it with this one or the G-Unique:
https://smallformfactor.net/forum/t...r1-atx-plug-in-400w-dc-dc-power-supply.13778/

There are a couple parts about this PSU that take it out of ATX spec. Its ripple is 200mv, test report shows 187mv at full load.

True. But that´s the max values, right? If we don´t push it to full load we should see better values here. But I´ll test it in a few days when I got my electronic load bench.
 
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k0n

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Jul 3, 2019
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I'm not a fan of external PSU's or risers/non standard components... still I did this: 5L

Back then I didn't plan on using a fan and also thought about mounting the PCB on a heatsink instead of using standoffs. What keept me from doing it was the fear of cooling the wrong components... Possibliy removing the overheating protection.

For projects with internal PSUs it's best the way it is... because of the flexibility. If I where to design a case for it it would be to a existing standard... Flex-ATX.

For external use it should be passive and sealed... Epoxy + Al2O3 powder is something I wanted to try for a long time. Will it be enough to at least match cooling with convection?
 
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REVOCCASES

Shrink Ray Wielder
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I'm not a fan of external PSU's or risers/non standard components... still I did this: 5L

Back then I didn't plan on using a fan and also thought about mounting the PCB on a heatsink instead of using standoffs. What keept me from doing it was the fear of cooling the wrong components... Possibliy removing the overheating protection.

For projects with internal PSUs it's best the way it is... because of the flexibility. If I where to design a case for it it would be to a existing standard... Flex-ATX.

For external use it should be passive and sealed... Epoxy + Aluminiumoxide is something I wanted to try for a long time.

well, its supposed to be a slightly smaller alternative to the HDPLEX 400W AC-DC brick. Same here, you could use it inside or outside of the computer case like many people are doing it. Combining it with a powerful plug-in (pico) PSU you`ll have some really flexible options. I mean the HDPLEX form factor was also not a standard until they made it one.
 
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REVOCCASES

Shrink Ray Wielder
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Epoxy + Al2O3 powder is something I wanted to try for a long time. Will it be enough to at least match cooling with convection?

Many passive cooled external bricks are filled with epoxy. We are doing this since many years for heavy duty emi filters to keep them cool. But you'll have to choose the right one else you'll damage the components (e.g. inductors and caps) during curing. why do you need that powder?
 
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k0n

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Jul 3, 2019
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I know its in use in many applications but what do they use to increase thermal conductivity of the epoxy?
 

REVOCCASES

Shrink Ray Wielder
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I know its in use in many applications but what do they use to increase thermal conductivity of the epoxy?
There are special compounds for this application. These also stay elastic to prevent damages. Just have a look to the 3M website for example. They offer different mixtures for different applications. Also with improved heat conductivity.
 
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scatterforce

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May 21, 2018
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@ Till - Revoccases Have you considered these two products?

UHP-350-12
UHP-500-12

I'm surprised more people have not found or considered using these. The 350 watt PSU could fit underneath the GPU in a sandwich style case. Either of these would be better suited for an external PSU IMO, as they are narrower and less chunky; they are most likely to fit behind a desk or tucked away somewhere. Adding a quiet noctua fan like this next product would be great:

RMRC 12V 400 W

I suspect this last option is too far out of spec for a PC application, but the idea is sound. A central exhaust/intake fan to pull/push out the heat while keeping the total size very small.

Whatever you decide to do, I'm interested in your work. If I decide to water cool my current build, the only way to do that is to remove the SFX psu... and I do not have enough room elsewhere for a HD-plex unit.
 

REVOCCASES

Shrink Ray Wielder
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@ Till - Revoccases Have you considered these two products?

UHP-350-12
UHP-500-12

I'm surprised more people have not found or considered using these. The 350 watt PSU could fit underneath the GPU in a sandwich style case. Either of these would be better suited for an external PSU IMO, as they are narrower and less chunky; they are most likely to fit behind a desk or tucked away somewhere. Adding a quiet noctua fan like this next product would be great:

RMRC 12V 400 W

I suspect this last option is too far out of spec for a PC application, but the idea is sound. A central exhaust/intake fan to pull/push out the heat while keeping the total size very small.

Whatever you decide to do, I'm interested in your work. If I decide to water cool my current build, the only way to do that is to remove the SFX psu... and I do not have enough room elsewhere for a HD-plex unit.

Yeah, I have also thought about the UHP series. Especially the 350w version looks interesting. Looking at the specs this could be probably pushed a bit more than 350w with a better cooling solution.

The question is if people could fit it in their cases because it's quite long? Used as external brick I think it wouldn't really matter if we use the UHP or RPS. One is long and slim the other is shorter but thicker. Anyway it will be much much smaller than the huge DELL bricks I'm currently using.

That other PSU you found I honestly wouldn't trust. From my experience you can't get a small, reliable and powerful PSU for that price.
 

REVOCCASES

Shrink Ray Wielder
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Now a general question in which direction the project shall go:
Do you prefer a internal solution or use it as a external brick?

My thoughts

External: Makes most sense from my point of view. It frees up space in your cases for more important things like storage, water pumps, bigger CPU coolers, etc... And it will be much smaller than typical AC-DC bricks with that wattage so you can easily hide it somewhere.

Internal: a bit smaller and cheaper compared to the HDplex AC-DC brick but not much. Compared to FLEX you wouldn't gain anything except the cost advantage.
 
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REVOCCASES

Shrink Ray Wielder
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Some test results with the RPS-400:

Using my new DIY electronic load I've pushed the power supply up to 35A at 12V. Ripple and voltage drop are totally fine.

I only tested for 5 minutes because the electronic load gets too hot and needs a bigger heatsink to get rid of that wattage... Anyway looks promising.

 
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scatterforce

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Anyone can already mount a Meanwell PSU inside of their case. I don't think there is a need to sell a kit for that, especially with the competition from HDplex.


I would go external, but would suggest the UHP series again. If someone puts a brick on the floor behind their desk, then it will suck in a lot of dirt/carpet/pet hair/etc. The UHP series doesn't need active cooling; instead, they must be mounted to an aluminum plate 450 x 450 x 3 mm. I don't know the logistics behind making a finned enclosure for an external PSU, but I for one would prefer that than something with a fan (cat owner here).
 

REVOCCASES

Shrink Ray Wielder
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Anyone can already mount a Meanwell PSU inside of their case. I don't think there is a need to sell a kit for that, especially with the competition from HDplex.


I would go external, but would suggest the UHP series again. If someone puts a brick on the floor behind their desk, then it will suck in a lot of dirt/carpet/pet hair/etc. The UHP series doesn't need active cooling; instead, they must be mounted to an aluminum plate 450 x 450 x 3 mm. I don't know the logistics behind making a finned enclosure for an external PSU, but I for one would prefer that than something with a fan (cat owner here).

But if I can make the RPS into an passive cooled brick, are you in? Or does it have to be the UHP?