Dmwardjr,
I am looking at your setup and just completed my 100amps setup at my outdoor shed.
My electrical knowledge is limited and need some advise.
I measured that each S7 draws about 5-6amps @ 1200watts each.
I use Bitmain 1600 PSUs for all the S7s I have currently.
I have 4 x S7s and intend to setup 6 more S7s.
10 x S7s is my maximum that I can afford for electricity.
How many S7s can I hookup with 80% load?
How many S7s will you hookup to your 600amp monster?
Thanks
TMT
I just got back from a birthday party. I'll answer you properly in a PM. Give me a little time. I also need to know which batch S7's you have at present. Depending on the batch, some may consume more watts (power) than others.
Also, the 80% is only limited to each individual circuit and not the Main Service Panel. For instance, lets say you could spare 100 amps x 240 volts = 24,000 watts from you Main Service Panel (MSP). The MSP is not limited to 80% but each individual circuit is. This means you will simply have to add more circuits to reap the full benefits of the 24,000 watts available from your MSP in order to be safe.
If each of your circuits are 240V / 30A, that is a total of 7,200 watts. 80% of 7,200 watts = 5,760 watts. IF each S7 you have is 1,210 watts each, you could have 4.76 S7's on each 30A/240V circuit. So, not quite 5 x S7's. If each of your S7's are 1,293 watts each, that would be 4.45 x S7's for each 30A/240V circuit if kept at 80%. Most say to keep at 75% and many local electrical ordinances say 75%. Also many insurance companies for Data Centers demand for them to keep each circuit to 75% instead of 80%. I would imagine there is some lead way. Meaning, the insurance company might say, "Keep each circuit to 75% +/- 1% or 2%. It's best just to keep each circuit at 75%. This simply means you add more circuits while keeping only 4 x S7's on each 30A/240V circuit to be on the safe side.
If you had 4 x S7's at 1,293 watts each, that would be 5,172 watts of the 24,000 watts available from your 24,000 watt setup with 100A service. This equals 4.6 circuits. Which means you cannot quite have 4 x S7's on that fifth circuit. 5,172 watts x 60% = 3,103 watts. This means your fifth (5th) circuit can only have 2 x S7's on it.
Now, look at this: You say you already have 4 x S7's at 1210 watts each. That's a total of 4,840 watts. If we subtract that from 24,000 watts available, that leaves 19,160 watts. Well, the only S7's available now are batch 8 @ 1,293 watts. 19,160/1,293 = 14.8 x S7's. If we divide this by 4 x S7's for each circuit, this leaves 3.7 more circuits. So, again, not quite 5 circuits with 4 x S7's on each circuit. However, that ".7" of "3.7" means something: If you had 3 x S7's batch 8 @ 1,293 each = 3,879 watts. If we had 4 x S7's batch 8 on a circuit, that would be 5,172 watts. That ".7" [or 70%] of 5,172 watts = 3,620 watts. We just saw that 3 x S7's batch 8 @ 1,293 each = 3,879 watts. So, still not quite enough available there for 3 x S7's batch 8 on that 5th circuit.
I personally believe you will be limited to 4 x 30A/240V circuits running at 75% on each circuit. Then have only 2 x S7's batch 8 on the final circuit. This will leave enough power (watts) remaining for one or two large fans. One for out-take to suck heat out. The other to suck air into the structure for good airflow and to offset static pressure. I have two 7,400 CFM fans [One for out-take and one for in-take to reduce static pressure in my house and to provide good airflow. Each one of these fans are 120V/2.5A (300 watts) each. If yours is or will be similar, that is another 600 watts needed anyway for fans to keep your rigs cool.
So, in conclusion, I see 4 x 240V/30A circuits running @ 75% with 4 x S7's on each circuit = 16 x S7's. And, another 2 x S7's running on a 5th circuit that can simply be a 20A 2 pole breaker at 75%. Then you can have one or two circuits {doesn't matter} at 20A/120V for your in-take and out-take fans, modem, switch, etc.
This means 18 x S7's at stock settings [Not over clocked] total with all of your peripherals. If you over clock, it's a total different story.
EDIT: I'm not sure how well the S7's under clock? Meaning, they may still consume pretty much the same amount of voltage even when under clocked without a PSU that you can adjust the output voltage. I mention this because you might consider under clocking to add more rigs.Something else, you need to know for sure the exact voltage provided by your transformers. 2 pole or phase voltages can vary from 208 to 240. It all depends on how the power company is providing the power to your house. I'm assuming you have 2 poles (phases) in your Main Service Panel and not 3 poles (phases)? If you had 3 poles 100 amp, you would have more power (watts) available than what I've mentioned.
How would you KNOW exactly how many volts is provided on two poles combined [208 to 240]? You need a multi-meter with lower internal resistance than normal when measuring AC/DC voltage. I recommend the following meter to measure your voltage across 2 poles: The Triplett Model 310. It doesn't matter if it's 310A, B, C or D.
http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2060353.m570.l1313.TR0.TRC0.H0.XTriplett+model+310.TRS0&_nkw=Triplett+model+310&_sacat=0Most digital meters have a higher internal resistance [When measuring voltage] and will give a higher reading. Meaning, if you see 240 Volts with a digital meter, you might actually have only 220 Volts. Using the Triplett Model 310 [With a much lower internal resistance] will give a more accurate reading of the actual Source Voltage you have. If it turns out you have only 220 Volts, it may be the power company has installed a transformer that's capable of stepping up the voltage to 240 by simply terminating your feeder cable at a different position on the coils in the transformer.
EDIT #2: Also, if you have only 220 Volts instead of 240 Volts, these figures I've come up with will change in terms of how many watts available for a certain number of rigs.It's possible I could have overlooked something. Anyone else is welcome to chime in. I PROMISE, I won't bite.
David
PS- I'll add what I'm doing in within another hour. I just wanted to get posted what you needed to know first.
You won't find anything contradicting what I've said about derating the MSB.
1385Gh binary v2 
