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hey guys,
I'm sure this has been beaten to death in the past but would greatly appreciate a bit of input.

1. How many S9s can I safely connect to a 220V 50A line?
I was reading that each S9 needs about 7-8A.
So I was thinking that 5 should be ok. Please correct me if I'm wrong.
2. Would 6 be pushing it and be out of the safe limits???
3. What gauge wire should be used for such a line?
4. Any recommendations for an affordable, time-tested switched pdu? ($200-$250 range)

I'm setting up a small op, will be starting with 3 but planning on adding more soon.

any help is greatly appreciated
thx

1375w = 6.25 Amps wired as single phase 220V, 5.73 Amps at 240V.
You should be able to run 6 max if leaving 20% safety load (40 amps). 8 would be near 100% load at 220V or 240V and pushing it.

8/2 wire is what I use for 50 amp breakers and will safely handle 40 amps.

If you want to try pushing 100% breaker load, you'd need to run 6/2 wire, which can safely handle 55 amps.

You will probably not find an affordable PDU to run all of that off a single outlet. Most PDUs are rated at 20 or 30 amps max, so you'd need 2 PDUs and 2 outlets. May want to run two 30 amp breakers/outlets with 10/2 wire instead, which is rated to safely handle 30 amps. 

I'm fond of running 20 amp breakers, so three of those, with (2) miners on each, would be quick, and uses much easier to deal with 12 gauge wire:

Even figuring 1500 watts (14000*0.098/0.93 plus a bit for fans and the controller board) at 220V you only at 6.82 amps.  Of course if you have a 13.5TH instead of a 14TH, they would take proportionally less.

Anyhow, 6.82*2 = 13.64 amps per breaker.  13.64/20 = 68.2%, so doing great there per circuit.

6.82 * 6 total miners = 40.92 / 50 amps = 82%, so pushing that just a bit.

Bottom line, (5) 14TH should be absolutely fine, and you might get away with 6.  (6) 13.5TH boxes should also be fine.

really appreciate all the info guys.
I think I will have to go with 2 x 30 Amp lines.
Reason being, I am yet to find a 50A pdu under $1k.
I think I might have to ditch the switched version also... so basically just use the pdus as glorified extension/expansion cords.
I still need to find a way to set up remote access/power cycle.
Worst case scenario... I will be having 3gpu rigs there as well, running Win 10 with Teamviewer and guess i could use one of them as a main access point for the network to log into the ants.
That would take care of remote access but still need a way to power cycle remotely.

I have been using the tp-link smart plugs (with kasa) at home for the gpu rigs and they do work ok but no clue what I could use on the c13/c14 plugs for the ants

Any ideas?

I was thinking of getting 2 of these:

https://www.ebay.com/itm/202248089627 (https://www.ebay.com/itm/202248089627)

if anyone has any better options please feel free to share

What is the purpose of a PDU if not for remote switching?

I just use a 20 amp 2 pole breaker to drive a duplex 20A 250V outlet for each pair of S9s.
I use 12/2 with ground wire cable. It has a yellow jacket conforming to the newest jacket color code. 

All the parts are cheap and readily available from Home Depot, Lowes or ebay.

If you need to add more S9s, just add a sub panel. These are also cheap and off the shelf available.

They are highway robbery.

172 each is a rip off

eBay item

332572578907

https://www.ebay.com/itm/HP-EO4501-Modular-Rackmount-Power-Distribution-Unit-228481-002-24A-200-240VAC-/332572578907?


Much better

Does 4 s-9s only 70 or best offer

What are your psus?

https://www.ebay.com/itm/NEW-8-2FT-2-5M-250V-16A-C19-to-C20-PDU-Server-Cord-DP-N-2X976/281944781556?


https://www.ebay.com/itm/4-foot-Power-Cord-Black-NEMA-C20-to-C13-14AWG/301969734091?


one of the two above should work.

if you have 2x

 30 amp breakers

you may be able to do 4 s-9's on each pdu

you will be able to do 3 s-9's on each pdu for sure.


a lot depends on heat  and your voltage  I am lucky I get 242 in from the street and sag to 239

so 24 x 239 = 5736 watts  or 4 s-9's

again, I greatly appreciate all your input guys.

omg phil, thx for those links... you're a life saver.
I will definitely go with the HP pdu and the c20 to c13 cords.
The psus are the apw3++ (got them with the ants from bitmain)

Saturday we'll have the electrician come over and see what we can do.
This will be set up in a friends basement I guess we'll have to wait and see the voltage lottery coming in from the street.

Any tips on how to set these up to be power cycle-able remotely?
Is there a c20 smart plug that could work with these??? not sure how steady/reliable these S9s are... back in the day my S1 would go for months unattended.
I guess I'll have to manually reboot them if nothing else. (which will suck cause my buddy's shop is across town)

I used to get power cycle pdus cheap on ebay not any more.

Hey Phil,

after banging my head all night trying to find a switched pdu I came across this one:
https://www.ebay.com/itm/263395755382 (https://www.ebay.com/itm/263395755382)

would you say it's worth it???
3x more than the HP but it is rated at 32A

so 32x230 = 7360W

so 5 ants? safely?
and it's switched.

I looked it up on the manufacturer's website. this is a 2016 model and the msrp was $2300??? that sounds a bit crazy.
The plug is a commando 32 (w/e the f that means). I'm sure I can make it work as long as it is a US standard.

Let me know what you think.

Other than the weird plug it looks nice. But, you'll need an outlet to match that plug. So talk to an electrician or do some research. Also notice that PDU is split in to 2x 16A circuits. This is why PDUs are a pain in the butt, they are generally for data center use where you have lots of low amp draws. I had posted some low outlet count PDUs (this higher amp per outlet), you might search for those part#'s as well as some of the recommendations in that thread.

Very true. I missed the whole 2x 16A circuits thing.
Still, I think it is the cheapest switched pdu on ebay for 220V+.
I think I might be able to have 2x S9s + 1x gpu rig /circuit. I'd be ok with that, knowing that I can power cycle them remotely.
Then again, maybe I should just go with the HPs phil mentioned. They seem sturdy/rugged and would probably last the lifetime of the ants.

It just bugs me knowing I won't be able to reset them remotely.
If I had them at home it wouldn't be a problem, but having to drive across town to unplug something is just stupid.