Are Redundant PSU Adapters a Thing?

Zarathustra[H]

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Essentially, is there any adapter thingamabob I can use, presumably some sort of power distribution board with two PSU inputs and one PSU output that goes to the motherboard and other devices, used to take two ordinary ATX PSU's and have them operate in a redundant configuration, like an enterprise server would?
 

sinisterDei

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They do, yes. https://www.amazon.com/Phanteks-combine-Redundant-Function-PH-PWCOB_2P1M/dp/B01E9YMX4I/

No clue if the dang thing works or not, just FYI. Also no clue how you're supposed to power SATA devices? And I guess good luck if you need more 8-pin connectors? Maybe there's a newer version or something, but that's all I got for now.

However, be careful to connect only two similar, quality power supplies to such a device. The problem is, and pardon me I'm not an electrical engineer so I am likely to butcher this a bit, that two power supplies may have enough output variance that they would 'interfere' with each other if directly connected. One PSU outputting 12.01V and one putting out 12.04V or somesuch would be bad if you mixed them together. I presume actual redundant power supplies spit out their power to some kind of circuitry that handles this variability and reconciles them to a single output that then connects to the equipment, and I presume that is what this device is doing as well. Presumably, even with the right circuitry the tolerances would still need to be tight, so I still wouldn't try to make a 'redundant pair' of PSUs out of wildly different quality power supplies, where the variance is much more severe than the little adapter board can handle.
 

Smoblikat

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They do, yes. https://www.amazon.com/Phanteks-combine-Redundant-Function-PH-PWCOB_2P1M/dp/B01E9YMX4I/

No clue if the dang thing works or not, just FYI. Also no clue how you're supposed to power SATA devices? And I guess good luck if you need more 8-pin connectors? Maybe there's a newer version or something, but that's all I got for now.

However, be careful to connect only two similar, quality power supplies to such a device. The problem is, and pardon me I'm not an electrical engineer so I am likely to butcher this a bit, that two power supplies may have enough output variance that they would 'interfere' with each other if directly connected. One PSU outputting 12.01V and one putting out 12.04V or somesuch would be bad if you mixed them together. I presume actual redundant power supplies spit out their power to some kind of circuitry that handles this variability and reconciles them to a single output that then connects to the equipment, and I presume that is what this device is doing as well. Presumably, even with the right circuitry the tolerances would still need to be tight, so I still wouldn't try to make a 'redundant pair' of PSUs out of wildly different quality power supplies, where the variance is much more severe than the little adapter board can handle.
Neat, didnt know that existed. Technically I guess you could implement RAID1 (or any mirroring RAID) and power an equal number of SATA devices off of each PSU, might not be the best solution but it works in theory.
 

Zarathustra[H]

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They do, yes. https://www.amazon.com/Phanteks-combine-Redundant-Function-PH-PWCOB_2P1M/dp/B01E9YMX4I/

No clue if the dang thing works or not, just FYI. Also no clue how you're supposed to power SATA devices? And I guess good luck if you need more 8-pin connectors? Maybe there's a newer version or something, but that's all I got for now.

However, be careful to connect only two similar, quality power supplies to such a device. The problem is, and pardon me I'm not an electrical engineer so I am likely to butcher this a bit, that two power supplies may have enough output variance that they would 'interfere' with each other if directly connected. One PSU outputting 12.01V and one putting out 12.04V or somesuch would be bad if you mixed them together. I presume actual redundant power supplies spit out their power to some kind of circuitry that handles this variability and reconciles them to a single output that then connects to the equipment, and I presume that is what this device is doing as well. Presumably, even with the right circuitry the tolerances would still need to be tight, so I still wouldn't try to make a 'redundant pair' of PSUs out of wildly different quality power supplies, where the variance is much more severe than the little adapter board can handle.
Appreciate the link. I did a lot of googling and never found that one. It is indeed curious that it does not have any connectors for drive power, but in my case that doesn't matter. It is for a pfSense box I want to take power from two separate UPS:es as backups of eachother, and the only drive on the thing is a tiny m.2 SATA SSD.
 

sinisterDei

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Ditto Blue Fox. No reason for trying to redundant up the PSUs if you are just trying to get some form of A/B power. Now then, if you want redundant UPSs *and* redundant power supplies, then you must have some serious needs for uptime and should probably just plonk down the dough for an actual redundant PSU :)
 

Zarathustra[H]

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You want an automatic transfer switch, not some frankenstein attempt at hooking up two ATX PSUs.
Well, this is a commercially available product. I'm sure it has undergone some testing.

The reason I like it over a transfer switch is that it distributed the load across the two PSU's so I can draw down the UPS:es evenly.
 

Zarathustra[H]

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Ditto Blue Fox. No reason for trying to redundant up the PSUs if you are just trying to get some form of A/B power. Now then, if you want redundant UPSs *and* redundant power supplies, then you must have some serious needs for uptime and should probably just plonk down the dough for an actual redundant PSU :)
It's not the money that is the disincentive here. I was looking at the FSP redundant units. Problem with those is that they are so much higher capacity than I need.

The pfSense box is currently running off of a single 60W PicoPSU unit from Mini-Box, which allows me to draw single digits watts from the wall at idle.

If I were to put a big honking 700w redundant PSU in there my efficiencies would go to absolute shit.

Dual PicoPSU's in a redundant configuration - however - would be awesome.
 

Zarathustra[H]

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What mobo are you using that you can power with the 60W PicoPSU ?
It is an ASRock H270M-ITX/AC.

Full specs as follows:


I yanked the wireless module out to reduce power waste.

Actually this is a little old. I have since transplanted it into an iStarUSA 2U rackmountable chassis.

Load tested for several hours with mprime, so I know the 60W PicoPSU is sufficient.

I've done the same thing with three other systems, two Haswell Celeron's (G1840) and one hexacore i5-9400 (though I used a larger capacity PicoPSU for that one)

I mean, running it in a *nix box without a GUI on the integrated graphics helps too.

Truth is, as long as you aren't pushing things (overclocking, adding lots of drives, many powerful fans, etc.) these systems can be remarkably power efficient.

Actually, you'd be surprised how large a percentage of the typical PC power consumption is used by fans alone. Reduce the need for fans, and you significantly reduce the need for power.
 
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Blue Fox

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You're worried about UPS load with a 60W PSU and actual draw that's a fraction of that? If you need more runtime, get a larger UPS or expansion units for it if yours supports it. How many hours do you really need for a router when everything else is going to be dead long before it manages to drain any UPS?
 

Zarathustra[H]

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You're worried about UPS load with a 60W PSU and actual draw that's a fraction of that? If you need more runtime, get a larger UPS or expansion units for it if yours supports it. How many hours do you really need for a router when everything else is going to be dead long before it manages to drain any UPS?
I'm trying to split everything equally. This is just one load among many. Things add up.
 

Blue Fox

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Then balance the loads so that they're similar or get a bigger UPS. You're making this unnecessarily complex and trying to spend money on things that could be put to say another UPS.
 

Zarathustra[H]

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Alright,

So, this Phanteks device doesn't really seem to be intended as as a redundant power supply. It's more intended as a PSU doubler (which makes no sense when here are more capable PSU's).

The truth is that it works though. Just like redundant power supplies, it splits the load between the units, and if you unplug one at a time it keeps running. Just what I was looking for :)

IMG_20200915_212453.jpg


IMG_20200915_212459.jpg


Much more efficient than any set of official redundant power supplies on the market.
 

Kardonxt

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So, this Phanteks device doesn't really seem to be intended as as a redundant power supply. It's more intended as a PSU doubler (which makes no sense when here are more capable PSU's).
It may be more geared for GPU miners? I normally just jump started the second PSU all janky like lol. Something like this would turn both the PSU's on and off with the system.

I'm glad it's working for you, looks very nice!
 

thesmokingman

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Alright,

So, this Phanteks device doesn't really seem to be intended as as a redundant power supply. It's more intended as a PSU doubler (which makes no sense when here are more capable PSU's).

The truth is that it works though. Just like redundant power supplies, it splits the load between the units, and if you unplug one at a time it keeps running. Just what I was looking for :)


Much more efficient than any set of official redundant power supplies on the market.
It's just a 2 PSU cable but 8x more expensive.
 

drescherjm

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The few negative comments about the device catching on fire are pretty scary. I assume they used more power than the device supports. With that said I expect for such a system as pictured you will be totally fine.
 

Zarathustra[H]

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The few negative comments about the device catching on fire are pretty scary. I assume they used more power than the device supports. With that said I expect for such a system as pictured you will be totally fine.
That's the exact conclusion I came to.

I don't think they read the specs and used it with too large PSU's.
 
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