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Hi I was hoping someone could quickly educate me as why a power distribution unit, like those used in data centers, don't seem to be used to power the mining ASICs? It seems like everyone buys an S9 and an associated power supply.

Is there not a better or more efficient and large-scale way to supply power to the miners than by purchasing individual PSU's for each?

I am trying my best to become more IT knowledgeable and it's tough   :-[

A pdu does not provide power,
Servers in server farms have their own internal power supplies.
Miners are external, the PDU is just a large fancy power bar.
Some times with remote control ability.

They are not use much because they are just an expensive power bar so many people od not require them.

 A PDU is generally a "fancy power bar" with at least minimal current and/or voltage monitoring, and often switch-controlled or even remote switch-controlled outlets.

 It DOES NOT replace a power supply in any way shape or form.

 It is often used as a fancier or more flexable version of a "secondary power distribution panel" + outlets wired to such a panel.

https://i.imgur.com/y3lzjll.jpg

https://i.imgur.com/4B4xMTZ.jpg
      
                                              ::)

The best way is to have individual PSU for S9 ASIC, well unless you find a more efficient way to turn your AC (alternating current) to DC (direct current).

Also for a house to have both AC and DC is very confusing so forget about it and don't save on that PSU :)..

IF you are talking about a few hundred KW of power on up, then yes using a high DC bus fed from the mains followed by local bus DC-to-12vDC is worth considering. HP, IBM and others all have DC fed 12v PSU's available just for that purpose.

The power eff advantage comes from losing all of the the normal input brute-force mains-to-DC and PFC power conversion stages found in each of the normally AC-fed local 12v PSU's. Instead a single several hundred KVA 3-phase transformer with full-wave rectified delta-wye secondary provides what is essentially pure DC with less than 0.7% ripple and no further filtering needed. Typically that high DC bus is around 300vdc or more which is also what the input stage to a normal 208vac PSU feeds to the power conversion stage that make the 12v.

Yes. This is exactly the answer I'm looking for. I can't say I fully follow what you are saying, but I think I got the gist. I'll do more research so I can understand properly.

For the application I am thinking about, I will be using somewhere around 30-80 kW. Would you say this is too low for me to consider the solution you are suggesting? It would just be nice to avoid purchasing individual PSU's and instead design the electrical distribution system around it.

The cost of the system and rails is REALLY high and not really something to be found used.
So more so for a big new build.
For your want.. you could get 5 or 6 of the 8kw setups from the guys on here, and be ready to go

Direct DC is not a real option for your needs

Here's what I'm meaning.
10 of these would be 80kw.
I can't even find a single 80kw DC output device to link you...

https://bitcointalk.org/index.php?topic=1667131.0

The incoming AC mains to high DC bus feed is by no means an off-the-shelf item... As in ALL high power distribution systems they are custom-built per order often by companies such as ABB, Siemens, NTT, et al. The DC fed PSU's on the other hand are made by most commercial server-class PSU makers excluding Consumer type stuff.

The main link I have to folks who design & provide everything related to Data Center power gear is http://www.schneider-electric.com
Along the same vein they also do the cooling design as well. Many good whitepapers on power and cooling to be found there as well.

Found this which covers the topic in detail http://www.datacenterknowledge.com/archives/2015/06/25/380v-dc-power-shaping-future-data-center-energy-efficiency/
and http://blog.stulz-ats.com/dc-power-data-center

Thanks Takagari and NotFuzzy, I will check out these links over the next few days. I wish I studied computer / electrical engineering instead of Mechanical :P ... having tons of fun learning about this stuff though, it's never too late hey! I appreciate the help :)

Not sure if I'm missing one of Optimizer's boards, but I believe he only makes 2K and 4K (the 4K being similar in design to the ones I carry).  Is there a 8K (4xDPS-2000BB) that I'm missing? That would be a freaking beast, but not sure I see the advantage over 4K boards which deal with high enough current as it is.

PDU's can save you money over wiring multiples of smaller 15-20A circuits.  Instead you can wire in single 50A circuits with appropriate wiring/plugs/receptacles and end up with 8kW-capable circuits on 200+V.  If labour is also expensive where you are, I see it as being advantageous over wiring 4x individual equivalent 15A circuits to end up with the same 8kW of PSU's.  As mentioned earlier, they essentially act as a sub-panel, but can be had for considerably less than a sub-panel, and come with "receptacles" built in.  They can also be helpful if you want to mix smaller PSU's in with larger PSU's, as you can pick up C20 power strips which break one leg of the PDU into multiple C13 outlets.

Most pdu's are not built for mass power draw, so they are not as handy as people think. So careful which you buy.
Sorry my math was off or I typed wrong, 10 of the 4k boards would give you 40, not 80.
But you can scale up from there

You could very well be right.  I have always used 50A rated PDU's at 40A max continuous and never had a problem personally.  You do have to be careful to buy ones rated for the proper amperage, and not to exceed 80% of that like any wiring. Many of the network-enabled ones have pretty weak current ratings. Beyond that obvious safety stuff, do you think they are unreliable even at 80% of their max rating continuously?  I know you're pretty capable and probably do most/all of your own wiring, I often do as well.  However some people are (wisely) not comfortable doing that, and when you compare market labour rates to wire in 10x 50A circuits (to power 80KW continuous power @ 200V for example), and compare that to wiring in 40x 15A circuits in to achieve the same 80kW (even off a subpanel), many people will find PDU's can save money.  Plus it's nice to have breakers right on the PDU's compared to tracking down panels, and the aforementioned ability to use power strips off the C20 outlets, etc.  I like using them personally.

I like them,
Now that I found switchable ones, I'd really love to have a 50amp switchable one.
A lot of PDU online are 20-40 amp but have a lot of plugs, so mostly meaning people need to be careful.

The breaker right at the PSU is a great feature.
I do all my own work and work for others so it's hard for me to compare costs.
I wired a small sub panel for a buddy with a bunch of plugs right beside it. Essentially a PDU.

For the home miner, if you can get a PDU and stick a 50watt line in, thats your best bet. Safety and easy of use is a large part.
If yo go 240, those plugs cost more etc. PDU cuts down on that too.

If you're looking for some PDU specifics check out this thread.

https://bitcointalk.org/index.php?topic=2835305.0