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It seems life can be challenging for the US based miner who wants to use a 220v line for efficiency.

Let's use the Avalon 741 miner for example.  It pulls ~1150 watts.  That's as much as you can do on one 15 or 20 amp 110v circuit in the US.

However, if you have a 30 amp 220v circuit, you theoretically could have up to 4 of them on one circuit.  1150 / 220 = 5.2amps per unit.  80% of 30a is 24a.  5.2 * 20.9a, well within 80% tolerance.

But how do you wire the thing?  Do 30a 220v power strips exist?  Or do you daisy chain normal 20a 220v outlets together?  The power strip idea seems the best, however I don't seem to be able to find any online.

Thanks for the input!

M

Just bring an L6-30R to the "rack" level and use a PDU like this for local distribution.

https://www.tripplite.com/5-5.8kw-single-phase-basic-pdu-208-240v-outlets-6-c19-32-c13-l6-30p-10ft-cord-0u-vertical~PDUV30HV/

This was the first one I found but there's tons of different ones, APC/Schneider has a big range of them as well.  North American Data Centre's are full of these things.

They come in basic, metered or fully monitored flavours and price can get up there!

Edit:  Also look at the 1U horizontal versions as well, less outlets than the monster above and a lot smaller.
Like these ones: https://www.tripplite.com/products/power-distribution-units-pdus~15?1692=Basic

Thank you very much!  I knew they had to exist, I just didn't know what to search for.

M

eBay has good used ones

wait for a link

use 10 gauge wire and only one of these to your circuit breaker box  30 amp double pole 240 volt breaker

http://www.ebay.com/itm/L6-30R-Turn-Twist-Lock-Locking-Receptacle-Outlet-30A-250V-2P-3W-L6-30-U9W2-/122602838371?


good item below  can do

24 amps x 240   = 5760 watts  if you are lucky  you  get 239-241 volts from the power company

or 24 amps x 220 = 5280 watts  if you are not lucky you get 219 -223 volts from power company

http://www.ebay.com/itm/EMC-100-885-137-12-Outlet-PDU-Circuit-Breaker-200-240VAC-24AMP-100-885-138-/331940002835?


4 avalon 741's pretty easy 

 5 meh maybe maybe not.   depends on heat and volts.

Thanks.  Seems the PDU should be 30a, not 24?

M

I don't want to speak for philipma1957 but basically with the load you will be putting on the circuit a 24A PDU should work.  The issue isn't putting the 24A PDU on the 30A circuit the issue could come if you go over the 24A rating on the PDU (by adding more than the 4 miner load) as the 30A circuit won't clamp before the 24A PDU is overloaded.  If the PDU is protected locally it should trip, if not then shit will get hot, melt and spark and maybe other bad shit.

Line voltage matters because circuits are just thermal protection.  240 will allow more watts drawn than 220 as the math above shows before reaching the 24A thermal limit.  A "220V" NEMA rated PDU will be rated for voltages from 200-250 Volts at whatever amps it is designed for.

In the real world people don't generally allow or put branch circuitry with lower thermal protection than the breakers (with the exception of 15A receptacles on 20A circuitry in houses, but that's a whole different discussion!).  The potential to overload the outlets is to great to allow this as common practice.

Bitcoin mining is about shaving costs to maximize profit.  If you understand the mechanics, can do the math and are comfortable with it then hey certain options present themselves!

It is easy and cheap to wire up a subpanel. The subpanel boxes are $30 or so run a heavy wire on a big breaker to it and then use smaller breakers and wire for each miner. All available at Home Depot.

I ran 4 ga wire to a sub panel on 70 amp breakers  and put 8 110v 20 amp breakers in it. It will power 8 miners.

That's a decent idea.  Thank you.

M

Your welcome. Just be careful. If you are not familiar or comfortable doing this type of thing consult an electrician. I am not an electrician but I have wired up several shops, wells, etc and felt comfortable doing it myself.

Remember these loads are continuous so any standard amp ratings you see you need to multiply by .8 for example 12 ga wire normally on a 20 amp circuit is only good for 16 amps continuous.

Has anyone found a cheaper plate than this...

http://www.ebay.com/itm/Leviton-DuraPort-Industrial-1G-1-Port-Stainless-Steel-Wallplate-Cover-D6710-1S1/232466298672?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D1%26asc%3D46086%26meid%3Daed7f2dbb6d74a7b81d205438c320d46%26pid%3D100011%26rk%3D2%26rkt%3D4%26sd%3D391851141961&_trksid=p2047675.c100011.m1850

SERIOUSLY? are you kids too lazy or too incompetent to do a simple google search..or both...

How to set up 220v

www.youtube.com/watch?v=DqefJ2MQrRo&t=10s

Plug and receptacle
www.homedepot.ca/en/home/p.20-amp-flush-receptacle-250v6-20r.1000174840.html

Understood.  I'm building everything for no more than 80% capacity.

I did some quick math and it seems that the improved efficiency of using 220 instead of 110 will pay for itself in the long run, especially if your electricity is > $0.01/kWh.

M

Hey guys...I'm in the US, and getting a workshopped wired for 240v right now....so I ordered a couple of these....but they came with a plug like below??

http://www.ebay.com/itm/Perfect-EMC-100-885-137-Rack-PDU-Power-Strip-200-240VAC-24A-Carling-Technologies/142494153802?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D46089%26meid%3D0c601e5b7ae84320b3b0339dfa1c75f3%26pid%3D100005%26rk%3D1%26rkt%3D6%26sd%3D401192529590&_trksid=p2047675.c100005.m1851

Can anyone tell me what I'm to do with that?  Thanks...

Go with as high of an AMP rating as you can get. You never want to run your equipment at 100% of their design limit. 80% of the limit is generally considered safe for 24/7 use. I used 8 AWG copper cable between my breaker and the L630 receptacle as it has an ampacity of 40 amps so that gave me the overhead i was comfortable with.. From there, a used PDU from ebay is all you need just like phil suggested.

looks proprietary.. not worth trying to fool with it imo. trash it and get one with a common plug.

It might be less expensive to just wire up that 220v circuit with more than one outlet.

 There is NO REASON you can't do so - it's just not the norm in North America since most "220 outlets" are intended for high load items like electric driers and electric water heaters and central air/VERY high capacity window air units that DO soak 15 amps or more even at 220 while low-load items are normally wired for 110.

 DON'T do this if you don't know what you are doing though - just like ANY electrical work.

I've got to agree!!!

Here is my complete shopping list from panel to power supply...

Circuit Breaker to match your power panel
http://www.ebay.com/itm/NEW-SQUARE-D-HOM230CP-HOMELINE-30-AMP-DOUBLE-POLE-CIRCUIT-BREAKERS-6721344-/311302683815?epid=691118573&hash=item487b15fca7:g:fYcAAOSwPYZU7QzP

Some wire

A Device box
http://www.ebay.com/itm/Madison-Electric-MSB1G-One-Gang-Device-Box-with-Depth-Adjustable-/112438725322?hash=item1a2ddecaca:g:YFgAAOSw1x1UP4hK

An outlet
http://www.ebay.com/itm/Pass-Seymour-locking-receptacle-L6-30R-MADE-IN-U-S-A-30-amp-250V-twist-lock/390917364485?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649

Outlet cover
http://www.ebay.com/itm/NEW-LEVITON-Commercial-1-Gang-Stainless-Steel-Power-Outlet-Wall-Plate-84020-040/352146065381?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649

APC 4-outlet PDU
http://www.ebay.com/itm/APC-AP9570-Basic-Rack-Power-Distribution-Unit-PDU-1U-208V-30A-Rack-Mountable/391768769897?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649

Power cords
http://www.ebay.com/itm/Monoprice-3ft-16AWG-Power-Extension-Cord-Cable-3-Conductor-PC-Mon-C13-C14-Black/371192776255?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649


Based on the cost of circuit breaker, wire and outlet the PDU would be cheaper.

just found this pdu and grabbed 2 of them


http://www.ebay.com/itm/Genuine-HP-EO4501-Server-Power-Distribution-Module-228481-002/232449268221?


got this power cord

 4 of them  https://www.monoprice.com/product?p_id=24202


and  will use 2 of these psu's for each  pdu


http://www.parallelminer.com/product/2400-watt-power-supply-kit-for-gpu-mining-94-efficiency-200-240v-ethereum-eth-zec-dash/

Doesn't the 30 day warranty on the psu concern you?

M

Made by delta.    It seems good

Made by delta.    It seems good
[/quote]

I mis-spoke.  30 day warranty.

I'd be concerned about it frying my mining equipment.  Or worse.

It's like a car battery.  You could get the cheap 30 day warranty one, or the more expensive 5-year warranty one.

Perhaps I'm jaded.  I had bitmain PSU's blow a few days after their warranty expired.  Never again will I buy a cheap PSU.

M

 You have to have the breaker anyway, no matter how you set the circuit up.
 Same on the power cords.

 When I rewired the heaters in my current location, it cost me less than $50 ALL UP to set up a pair of 20 amp 220 circuits with 3 outlets EACH (though 20/20 hindsight I'm thinking I should have put 4 or 5 on each - I might end up changing that eventually.)
 I have NEVER seen a PDU that was $25 or less unless it was broken.

I was assuming you use 1 set of breaker/wire for each outlet as opposed to multiple outlets on 1 breaker.

If wire up multiple outlets, you don't NEED to use a PDU.

 8-)

Yep my farm is made up of a bunch of these

https://c1.staticflickr.com/5/4249/34728161806_5c57e5983a_b.jpg


6kw IOT PDU for 50 bucks worth of parts wired directly 30A breakers, with full control anywhere in the world on my iPhone :D

How much power does a 741 *really* use?  I have 245v at the wall, using the PSU above.  When I have two 741s running off one PSU, the PSU sounds like a jet engine.  When plugged into 3 of the 4 "cards" for two 741s, it sounds much better.

I've seen the 741 listed as using ~1150w, but I've also seen it say "+15%".  Which is it?  I have a killawatt, but it's the 110 version, so I can't measure the power usage.

Even if it's 1150w exactly, that's 2300w on a 2400w psu, which is pretty high imho.  I'm thinking two PSUs for three 741s is a much better idea.

Thoughts anyone?

M

I have been doing videos on sound control. 
I plan to demo 1 delta 2400 watt  doing 2   avalon 741's
I plan to demo 2 delta 2400 watt  doing 2   avalon 741's

I just got a clamp amp meter and measured the power usage.

With two 741s using the 94% PSU mentioned above, at 245v, I'm pulling 9.9amp of current.

That works out to about 1,212 watts of power a piece.

No wonder two of them caused a 2400w PSU to scream like a jet engine!

That also means that, even with 245v, they are pulling about 5amps a current a piece.  That means no more than 4 on a 30amp line.

BTW, this is with the 941s set to "-2" volts.  They are averaging 14.6TH/s between the two, which tells me that the -2 isn't doing anything.

M

I've recently ordered 5 of the avalon 741 for October 16th shipping.

I haven't purchased the power supplies yet.  Was planning on ordering from parallelminer.  Based on the comments of it screaming like a jet engine, do you recommend using one per 1200w version setup  or should I order dual  2400w one.  I know its cheaper to purchase the dual 2400w one, but of course there must be plus and minus to this.  Any suggestions?

Hi there,

I'm running this as my PSU at the moment with more on the way to expand.

http://www.ebay.ca/itm/Power-Supply-for-Two-x2-Antminer-L3-with-Complete-PCI-e-Wiring-Installed/182298369039?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

I can't say much for sound as the Miners drown it out, but it has been reliable and handles my 2 741's at stock, with no problems. Granted it has only been a week, but it seems to get the job done. They are also super helpful in getting set up and making sure you are using the right equipment.

For me it's just preference and cost that made me decide to double up on 220V PSU's. I have also heard it is more efficient to operate that way. Also you have to look at what you have available; for me it is easy to run another 30 amp circuit in my garage or basement and not worry about it, for others not so much. You have a few weeks to figure it all out just take your time do the research, and pick what's best for you.

Each 741 has two boards on it, each using 3 pci-x connectors.  Each board has to use the same power source, but you can use two different power sources for each board.

With that in mind, I'm going to use three 741s on two 2400w PSUs.  That should be about 1800w for each PSU for three 741s.

I do not recommend using a 1200w PSU for a 741.  If it pulls 1150, you are still way too close to the limit of that PSU.  For me, at 245v, on a 94% efficient PSU, they are pulling 1212 watts a piece, which is obviously over 1200w.

M

I like that idea, I knew I would be cutting it close so I talked to the manufacturer of my PSU just to be sure before I bought my 741's, he told me I would have enough for the 2 of them but to not overclock them.

I think you sort of figured it out for me.  Three 741's on two 2400w PSUs.  On a 30 amp line which is easy for me to run from the panel and then use the 30A PDU that will safely hook the two power supplies up.

This also leaves you a little room in case you swap out 741s for S9s.  Or whatever new stuff might be coming that uses more power.

M

I am running 1 2400 watt delta for each one.

Good results cuts down noise a lot.

Im not sure if I understand it correctly, but I think the problem here is how to get a 220V electricity to a 110V supply (US & Canada).

Easiest is getting a step-up transformer (110V - 220V). You will just have to bear with the extra heat and buzzing sound from the transformer.

Another way is just wire 2 110V line with different phase (antiphase) and 1 on ground from pole transformer to get 220V supply. Line that to a separate breaker.

Get a PDU and tap it there, then there goes the PSU for the miners.

transformer = badmove quality ones are costly and you still have a powerlimit.

your second idea is


a true 220 line from the breaker box  which is what is being discussed.

Here in the usa.  most of us have 2 separate hot lines    when  wired properly to a 220 breaker you get 220.

 I ran my S5/SP20 farm the same way when I had it - 3 miners on a pair of Seasonic X1250 or EVGA G2 1300 supplies.

 Just make sure each hash board is powered from the SAME power supply and you should be good to go.

 It also gave me plenty of headroom to crank that SP20 HARD (it was the "middle" unit on it's trio/pair).

here is a set of soundproof /psu videos for up to 3 avalon 721 or 741

https://bitcointalk.org/index.php?topic=2245487.msg22687179#msg22687179

this will work very well for a garage.

retracted

I can second that the transformer is a bad idea.  A few years ago we had a packing machine for another business that was setup for 220v but there was no way to pull a line to the machine because the commercial space leased at the time had a breaker box that was ancient and wasn't worth updating.  We tried this step up transformer box and it worked but it was very faulty and sporadic.  In the end we ended up not using the packing machine and it collected dust until we moved to another leased space which could accommodate  the wiring.

Just be careful with this.  These 220v lines are no joke, (heck that goes for all electricity). I see you've got it in a confined space and whatnot, but make sure no children or even adults messing around in the area.  You could probably get away with it at home or shed/outbuilding, but where I am in commercial spaces, I'd have to have it in conduit and plugs mounted on the wall.  My local fire marshal would have a field day if I tried this but then again I'm dealing with the public on a regular basis.

You built a Death Trap bro.  But I do agree it would work.

Yeah, I was going to say, this is wrong in so many ways.

M

retracted

I could give two shits about code,

What you built is a death trap it is not mechanically sound.

It allows for too much power if a short happens.

You are relying on the psu to shut down if you short. It looks like that psu can access all thirty amps

That is 7200 watts. Before the circuit breaker trips.

So unless the psu has multiple fuseing you gave it the ability to pull more then 4x what it is rated for.


Now if the line to the psu has been fused at the splices it would be mechanically sound but not code.

So did you put in fuses at each splice for each psu? If you did. It violates code but is not a death trap.

One reason I use pdus is they can come fused .

Much safer then allowing 7200 watts into a psu rated for 1600 watts.

I would also doubt you used power cords for the individual psus that are 10 gauge which are 30 amp rated


I buy used pdus from eBay.  So far about a dozen since I began mining.  I always pay under 50 usd.

They are all fused. They are worth getting .   I don't  believe in using multiple receptacles whengood low cost pdus can be purchased .

I don't rely on the psu to shut down if there is a short.