And I think your an ass for your assumptions.

I don't have to share any of my math with you. You can believe what you want. In fact it is a very good thing for me that you believe the way you do, so please keep thinking that way. I also hope you continue to spew your vomit because it helps me as well.
Here is a picture of a cropped screenshot of the ebay auction for the transformer on the left in that picture. Try to find a 500KVA 480/208 for that price. You wont.


Here is a picture of about 15% of the shelving we will ultimately need as we build to capacity. Also you can see in the back 3 400A panels uninstalled, a 600A breaker in enclosure.


Here is a older picture of just 150 3KW server power supplies, they sold originally from IBM for $1950 each. I paid on average ~35$ each for them. To the right you can see my crappy asicminer prismas that I bought from a group buy here. There is a reason they are sitting there. You can see a few of my 3 phase 60A IBM PDU's. They will monitor and record a dozen parameters on each outlet and can pull about 20KW each. I bought most of these for $40 each. Good luck finding them now I bought them all out of the market and they are only available for over $300 a piece now and I have 50. They came with 20feet of burly 6awg 4conductor cable hard wired so it saves quite a bit cable cost too. Oh, and it's the shitter on the other side of that wall.


I have good friends and family that help. I won't be putting all that shelving together. For example my brother in law, made this enclosure for my ammeters so I can see amperage on each phase. I will have one of these on each 400A panel, there will be 6 of them.


Sorry ASICSPACE guys for jackin your thread. I'll start my own when I think its time to show people how to build a mine junkyard wars style.

I've been to this facility at least a half dozen times. Not only does it exist but they are a legit operation. I'm sure BTC crashing to where it is now hurts because most of the installation came before this, when the math was better. They are hosting a number of machines for me until I get my own datacenter online which will be very soon now. As far as I know the recent issues was a network error that also propagated to all SP20's to require a reflash on them all. Not a job I would want, especially with an inbox piling up fast with legitimate complaints. I'm sure they could hire a customer service team to handle emergencies but then goes whats left of their profit margin. This is why I am planning on my mine as private, maybe a few larger clients that understand shit happens, especially when you are running the 'budget' type of datacenter. Not to say its 'budget', but face it, it ain't no Microsoft and they arn't charging those prices.

Wither or not you find it profitable to mine or see a possibility of a profit has no bearing on the topic at hand and only serves to troll.

And before I get accused as a shill or fake, here is a picture of my data center under construction. That is two 500KVA 480/208 transformers. Yes there is alot of work to be done.

Even in a fantasy world of free energy there would still be many costs running a btc mine. Electrical switchgear, copper, aluminum, enclosures, the building, cooling, internet+backup, mining machines, maintenance, permits, inspections, security, technical knowledge, etc, etc.. It would never be close to a zero sum game. Margins are thin enough at this point that you can blow away your chance at ROI even with free electricity just on infrastructure costs. Build like the government and procure with no questions asked and be damned, or be the junkyard guy that recycles usable equipment for almost free.

In cases where they actually may be 'free' power, I would argue that it is not so free because:
1. There is almost always a severe limit of capacity of power that is delivered freely.
2. Many of these places are in politically unstable areas, very risky to place any significant assets
3. Power quality tends to be very low, unstable, or power is not available 24/7/365,
4. Poor internet connection, specifically unstable or only high-latency connections available.
5. Someone is still paying for it, subsidized or not, so it may be free to you but someone or some group is still paying.

Forgot to add there are two main forms of 3 phase called 'delta' or 'wye'.

Here is a place where they get geeky about the sematics: https://www.physicsforums.com/threads/delta-vs-wye-pros-and-cons.682676/

TL;dr: wye will have 4 wires instead of 3, the fourth being a neutral, so if you tie any hot to a neutral you get 120v, and there is no 'wild leg' (all hots carry 208v).

All the wye stuff I have seen is 120/208/277/480v, take a look at this chart to see whats out there: http://www.ccontrolsys.com/w/Electrical_Service_Types_and_Voltages

If your going from hot <-> hot it will be 208/240v. But thats not a bad thing, unless you absoletely have to have 120/110 skip it. I'll bet all your bronze rated ATX PSUS's or better not older than 2 years will automatically switch and run better with the higher voltage.

Here is a picture of a box my brother in law made up for me, we will hang one of these above each 400A 208V 3-phase panel to have a visual proof of what is being used and how balanced. FYI these meters were $5.08 each off alibaba  (they also require a CT)

I will only be using 208V exclusively for miners, so none of the hots carry 120V. There are 5-wire 3 phase pdu setups that also bring in the neutral to allow you to go from phase to neutral to achieve that. I haven't been able to find any of those guys in the high wattage dept at the scrapyards.

You could engineer/wire it in a way that it pulls from two of the phases straight from the panel so you could use such an outlet on a three phase panel. That may be what he is doing and probably the norm. I'm setting up my datacenter with 3 phase PDU's so I bring all 3 phases out from the panels to closer to where it's used. More efficient that way, less metal to conduct more power.

That is a NEMA L6-30. for Single phase 240v applications, the three conductors you see there are for hot-hot-ground. Three phase will have either 4 or 5 conductors. They would be hot-hot-hot-ground, or alternatively hot-hot-hot-neutral-ground.

https://en.wikipedia.org/wiki/NEMA_connector#NEMA_6

This confused me too at first before I did some research into three phase. I like to think of it like this (and please pardon my newb explanations):

Single phase AC has two hots, with each hot maximum potential 180degrees out of phase each cycle(hertz)

Three phase AC has three hots, with each hot maximum potential 120 degrees out of phase each cycle. Think of this like a triangle instead of a teeter totter.

You can use Three phase as single phase, just use two hots from the three phase. Of course this will only put a load on one 'side' of the three-phase triangle. The additional trick needed for three phase is 'balancing' the load of all three 'sides/phases' of that triangle so power is pulled evenly. Ammeters on each phase can provide a visual representation of what is going on, or you can just depend on careful calculation and wiring. Transformer life and many other thinks can quickly deteriorate if you are running unbalanced in any significant way.

So with just one more hot with 3 phase, you essentially can pull single phase from three points.

An example with a 3 phase pdu I have: 3 phase power cord, 60A, @ 208V. It has 6 C-19 outlets on it. Outlets 1-2 are connected to Phases A-B. Outlets 3-4 are connected to phases B-C. Outlets 5-6 are connected to phases C-A. It will not self balance, but requires that similar loads are put on these groups of outlets.

Here is a number you should memorize (it is not exact but gets you close enough)

1.732

To calculate wattage available from 3 phase : AMPS X 1.732 X VOLTAGE

Hope some of this helps, three phase is cool beans!

If by Gen4 you mean super efficient miners that are yet to come out, it's impossible to account for everything that may happen in the future. But that said as long as they still require electricity and cooling in mass, of course they can.

I visited the ASICSPACE facility a few days ago and let me say it was clean! These people know what they are doing and did it right. They will be hosting quite a smorgasbord of miners for me while I get my own facility operational. They passed my own inspection with flying colors, very professional layout and very cold. HVAC is all there and very massive and impressive. Good job on this facility.

I visited the ASICSPACE facility a few days ago and it is by far the cleanest most professional mining space I have ever seen. Bulletproof work, very impressed. Good group of smart guys that really know what they're doing. They have backup plans/infrastructure to just about everything that can fail. As a paranoid bitcoin user that has been burnt more than once, it is refreshing to see such integrity. If you are looking for a place to send your miners, I cannot think of any better.

My first thought was some oversea big players with some cheap to free power. Still high bid was really around .2btc off the prisma price back in October. The SP15 15pack wins hands down at that price and considering we are bidding with a minimum of 20 that's really the best comparison to use.

I might as well publicly declare it here: I'm building a .5MW farm, and these would be a nice way to get a head start on more machines. The title thread has the words 'Round One' so maybe we will see this kind of auction again. I enjoyed it for what its worth.

I just received a PM from 'freidcat' saying I won my lot of 60 @ .52. I got pretty excited until I went to reply to the PM and looked at the same. Watch out for scammers guys.

60 @ .52 YUUUUUUUP!!!

Time to get this party started!? 

I'll start at 50 @ .30

I think the major screwup that Cointerra did was their decision to mine for themselves, rather than to sell hardware and allow their customers to take on the mining risk. The proof of this can be seen by their absurdly high miner prices over the summer. Had they not been so greedy and gone all long shot BTC to da moon, sold their hardware instead of build now completely unprofitable farms, they might have enough left over for round two. Hindsight is 20/20, but after having a few offers rejected by Cointerra over the summer for a few miner machines- fair offers IMO but apparently not good enough or bulky enough for them to bother. If anyone took the long shot bet here is by some higher ups at Cointerra that steer the ship to get the profit.

BTW I have one terraminer IV that still runs great and has run great sense delivery of April 2, 2014. April order, so you could say I even got mine on time. I'm sure my one terraminer paid for 3 at their farm, and they are worse off because of that alone. Greed killed this goose, it wasn't their customers.

These breakout boards have been performing flawlessly from the very beginning. The power supplies themselves are big and beefy but that only helps to keep them cool and efficient. When I load a DPS2000BB near 100% the custom fan job pushes some serious hot heat out of the unit. I have had almost a 30%+ failure rate on those units because of inadequate cooling. These get warm but I wouldn't say hot. I have noticed if the AC is plugged in but the power switch is off on the breakout board, something is still running, as the pws will get quite warm. A good tip would be to unplug or remove AC power after switching it off on the breakout board.

I think your most powerful miner will be the most efficient ones as well, Moore's Law and all that.

OMG Just do it! I could use some cheap ebay miners around March