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Hi guys & girls, as per title, how many of antminer S9 can i run on 150amps
240V 3 phase?

please ignore any use of power for router/exhaust fans/laptop/lighting.
The 150amps is purely for antminers.

TIA!

Each S9 uses 7A, so on 150 A, you can use 17 of them. 17*7=119 amps. And what is left is 20% (30 amps). So you don't hold full load of 150amps(or better to say 140 if you want to use 20 S9s)

thank you =)

so it means each phase can hold about 17 sets?
Total estimated I can run about 51 sets?

You sure about that?  I was under the impression a X amp 208V 3-phase supply could provide X amps to each of the A-B, B-C, and A-C legs - presuming those were separated out as they normally are for data centers.  Balancing the load between the legs is the only tricky part to optimize utilization.

That said, I've not worked with 3-phase, so don't know for sure.

sorry I might not have be clear enough, but currently I am running 32 sets of S9 on 150amps 3 phase 240V already.
So I dont think 17 is right. Hoping to see how many more can I add.

My electrician said 46 around there.. but I have been seeing different calculations throughout the net and was hoping for more answers.

Quick math, presuming some comfortable margin (7 amps per miner).  At 80% breaker load = 8.75 breaker rating amps per miner.    Anyhow, presuming each leg provides 150 amps maximum (limited by a breaker), you could have 150/8.75 = 17 miners per leg.  Roughly.  Thus 51 total.

Do you really have 240V 3 phase?  208V is much more common here in the USA.

I am from Asia. And we have very stable electricity at 240 :)

A suggestion. Do 45 not 51

Run 15 on each leg.

I say this due to a guess that you mine in a hot spot not cold.

Heat will reduce the psu efficiency so 15 per leg or 45 may be the safe way to go.

45 is still a lot more then 32.

You can keep 3 -6 extra and add them later if 45 work great .

When using 3 phase power you cannot use math that simple to determine the current per leg.

Your electrician can definitely confirm.

3 lines in 3 phases does not give you 3 times the current unless you use a Line to Neutral configuration. The rub in that configuration will be a lower voltage. Either way you wire it, Line to Line or Line to Neutral, the result will be the same power.

I actually measure 1530 Watts at 240V on my S9s at the Bitmain PSU input feeder breaker which is 6.4A.

So 3 of these is 4590W / 240V / SQRT(3) = 11.04A per leg

The circuit may only be loaded to 80% of its capacity so 11.04A / 80% = 13.8A circuit capacity per S9 trio.

OP's original question answer is;

150A / 13.8A = 10.9 (round up to 11 is legal to do) so 11 x 3 = 33 S9s


I share concern regarding the actual voltage of your circuit. I would be sure to first measure the voltages between each phase to ensure you really have the voltage you expect. People often generalize voltages which can vary enough to make a difference.
 

Hmm i use an adapter (i duno what you call it..multimeter or something? shows amp and volts and watts) and plug the socket ontop of a laptop and it shows constant 240V.
When i plug the adapter with S9 ontop, the fuse of the S9 power wire kinda blow i think. the wire no longer works, need to change a new wire.

If I were to snap a pic of how the DP looks like..would you be able to determine?

I'm not sure but I can try. Go ahead and post some pics.

Use this Calculator, will help when making decisions. http://myelectrical.com/tools/three-phase-calculator

Here is what I come up with @ 240VOLT -- 150AMPS and a .99 Power Factor You would have 61.73KW @ 100%

Now if You stick to the 80% Rule you would be left with 49.38KW which @ 1400watts per miner can hold 35 Machines.

If you say nah I don't care about 80% lets push it to 90% You could run 39. 40 machines would be just a tad over 90%

Since you are already running miners on the circuit, you can just get a clamp-on ammeter to measure each leg at the 150A breaker. The limit is 120A. If any two legs are less than 113A you can add one miner between those legs.  

People are taking liberties with the specs. 13.5 TH/s S9 spec is 1323W +10% at 25C ambient assuming the PSU runs at 93% efficiency. These specs are Bitmain's calculation model, not done by the mean of statistically significant sample measurements. Please also consider the power increase required to operate in 40C ambient conditions for both the miner and the PSU.

Note their power number is power with tolerance of +10%. It does not say + or - 10%. The 0.098 J/GH is 10% lower than the mean. That's why they stipulate to "expect" +10%. They really wanted to be under 0.1 J/GH because that sells more miners.

When I read all this I do not expect to measure 1455W maximum per miner. And I don't. I measure 1530W mean, at 25C. I don't know how much power to expect at 40C since I haven't been there to measure. I am certain it'll be higher.

All that above to share a point. The 80% circuit limitation is there partly to cover for temperature and specification maximums. Because Bitmain chewed up 10% and didn't account for 15C over normal temps, the circuit is actually at its practical limit if calcs show 80%. All that said it's no big deal in my mind as the breaker will just trip if you overload it. That is, assuming you follow all the other rules.