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Bitcoin => Mining support => Topic started by: BliksemMiner on November 28, 2017, 12:26:49 PM



Title: Three Phase Power (amp) Requirement for Antminer S9
Post by: BliksemMiner on November 28, 2017, 12:26:49 PM
Can someone please shed some light on Amp requirement for Antminer S9...

From the data provided - for one Antminer S9 the power requirement would be in the region of 5.6 AMP on a 220V supply. Would this requirement of 5.6 AMP decrease if you are running a three phase supply?
Does the three phase make a difference at all or is this supply only relevant to machinery that would utilize and rely on three phase?

Is there any benefit to having three phase?

Struggling to get my head around 5.6AMP supply per rig... For 50 rigs the supply seems huge!

Thanks you for your feedback in advance.


Title: Re: Three Phase Power (amp) Requirement for Antminer S9
Post by: fanatic26 on November 28, 2017, 04:49:22 PM
Your math is a bit off. 1400w / 220v = 6.36 amps. The power draw is what it is no matter what.

https://blog.tripplite.com/single-phase-vs-three-phase-power-explained/


^ a good quick read on the difference of 1 vs 3 phase


Title: Re: Three Phase Power (amp) Requirement for Antminer S9
Post by: big al on November 28, 2017, 05:34:09 PM
http://www.raritan.com/blog/detail/how-to-calculate-current-on-a-3-phase-208v-rack-pdu-power-strip


Title: Re: Three Phase Power (amp) Requirement for Antminer S9
Post by: BliksemMiner on November 28, 2017, 06:28:36 PM
Thanks.
Excellent reading material!


Title: Re: Three Phase Power (amp) Requirement for Antminer S9
Post by: big al on November 28, 2017, 07:01:36 PM
Thanks.
Excellent reading material!

No problem if you have any questons regarding the math shoot. I am not an engineer though.

If you have 3 s9s each drawing 6.36 amps one attached to each phase :

- Phase a-b, a-c and b-c are each drawing 6.36 amps
- each line has two s9s attached
- each line is drawing 11.01552 amps ( 6 36 x 1.732)
- watts and kwhr are still exactly the same as a single phase system


Title: Re: Three Phase Power (amp) Requirement for Antminer S9
Post by: BliksemMiner on November 29, 2017, 08:54:46 AM
Bi al are you saying that you can triple up on say a 60 AMP three phase ?

What I am asking is how many rigs can you run on 60 amps?


Title: Re: Three Phase Power (amp) Requirement for Antminer S9
Post by: big al on November 29, 2017, 07:12:52 PM
Bi al are you saying that you can triple up on say a 60 AMP three phase ?

What I am asking is how many rigs can you run on 60 amps?


With every 11 amps on 3 phase at 220 you can run 3 (one on each phase)

At 55 amps that would be 15. You could run 14 or 13 as well but not likely 16.


Title: Re: Three Phase Power (amp) Requirement for Antminer S9
Post by: sz921 on February 21, 2018, 02:33:01 PM
hi guys

so if i want to calculate the three phase capacity of my warehouse i should consider that each s9 need 1350 watt and the PSU capacity should be 660 watts???



Title: Re: Three Phase Power (amp) Requirement for Antminer S9
Post by: ccgllc on February 21, 2018, 05:21:36 PM
hi guys

so if i want to calculate the three phase capacity of my warehouse i should consider that each s9 need 1350 watt and the PSU capacity should be 660 watts???



Watts are watts.  A 50W light bulb pulls 50Ws if run at 12V (~4.2 amps), 110V (~0.45 amps), or 220V (~0.23 amps).  Because of the lower amperage draw at higher voltages, thinner wire can be used to carry the current.

e.g.  If your running a 1350 watt device, you need at LEAST a 1350 watt power supply/power supply efficiency.  For example:  if your power supply is 80% efficient (cheap and bad!), it would need to have 12V rails rated at 1350/.80 = 1688 watts and would be running at 100% utilization then, wasting (and generating heat for) 338 watts of power.  At 93% efficiency (APW3++), that math works out to 1452 watts with a waste of only about 102 watts.  You also need to check the efficiency curve for the power supply, since "efficiency" is often quoted at the optimal power draw for that device.

From the Bitmain page:  Power Consumption   1127W (11.5TH/s batch), 1225W (12.5TH/s batch), 1274W (13TH/s batch), 1323W (13.5TH/s batch), 1372W (14TH/s batch) (at the wall, with Bitmain’s APW3 PSU,93% efficiency, 25°C ambient temp). Expected discrepancy of +10%

The above statement from BitMain is either miss-leading, or lost something in translation.  At 0.098J/GH, a 13.5TH machine would consume 1323W JUST FOR THE CHIPS.  Their comment to add 10% however should compensate for the fans, controllers, support logic, and power supply inefficiency if your running one whose sweet spot is near 1350 watts at 93% efficiency, like the APW3++ is.

Regarding 3 Phase power, unless you have a 3 Phase power supply (VERY unusual), that 3 Phase power is likely just going to be broken into 3 single phase distributions.  Your challenge is to keep the load balanced across those distributions.