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Hey guys, I plan on installing maybe 10 miners in my garage. The thing is that I know each miners needs to be plugged on a 15 AMP breaker minimum, so technically ill need 150 AMP to make this project work. The issue is when i checked on my breaker at home I believe theres a maximum of 200 AMP for the whole house (maybe im wrong im not very good with these stuffs). What can I do? Can I call an electrician to install more breakers...? I don't really know if thats possible.. If someone know better let me know please it would help me a lot, thank you for your time

What miners are you running? I put in a 100 amp sub panel off of my 200 amp house panel. With 20 amp breakers. I can run 2 Antminer S9’s per breaker on 220v. They pull about 7 Amps on 220v so 10 miners on a 100 amp panel is no problem.

Call an electrician for sure. But, let's assume you are picking up 10 Antminer S9s. That's roughly 70A at 220. To cover 10 you'll need 4 30A circuits with 3 per circuit so you might as well buy 12 miners or round down to 9 :) Depending on how many you decide on, and you should always plan for growth, the electrician will probably recommend a 100-125A subpanel if your main panel has the capacity.

That's staying on the safe side, you *could* make 4 miners per circuit work, but you want you and your family to be safe so never run more than 80% of a circuit's capacity continuously.

Now you also have to address heat and noise, have you actually been near one? They are incredibly loud, like 80DB loud. And the heat is roughly 5,000 BTU. Now figure 10 of those and you need serious heat removal in addition to all the noise they make. You might just pick up 1 and go from there.

I did it like this.

1 x 125A two pole circuit breaker in your 200A panel

1 x 125 Amp sub panel

7 x 20A 240V two-pole circuit breakers
Each feeds a 20A 240V duplex receptical which feed 2 x Bitmain S9

This allows me to run 14 x S9s at <100 Amps typical so never exceeding 80% of the circuit ampacity.

If you need large fans or to carry other loads, you may need to reduce the number of miners to supply from this panel.

I think this is the lowest cost, conforming, way to configure the system.

I would not break any of the NFPA rules. You would not like to cause a fire then have the insurance deny your claim.

Since you do not have experience with electrical work, you really must hire an electrical contractor to file for permit and do the installation. It is highly improbable an inexperienced person could acquire all the information needed to safely install this type system via internet chats.

Hey there,

So with a little more info in regards to what miners you plan on installing in your garage will help.
 Here is a formula that breaks down electrical calculations to the simplest form watts/volts = amps

Using this if you were say running Avalon 821's
They are quoted at 1200 w.

You could set up 2 30 amp 220 volt circuits. And 1  20 amp 220 volt circuit ( or just make this a 30 amp like the others)
By using a PDU you can distribute the power to 4 miners per circuit.

The break down is that on a 220v circuit these miners draw less than 5.5 amps each(less because It's actually a 240v circuit)

You will probably want an electrician to install anything but it doesn't hurt to have an idea if what you need

I run my S9 in batches of 4/30amp (single phase) @220V...they draw 1350-1380 depending on the fan speed..so 6.5 Amps each or 26 Amps per 30 Amp line.
Yes this exceeds the recommended 80% load rule for lines
(which it is perfectly acceptable and legal in Quebec as they are a very stable draw with no power spikes, they have been fine for many month without any issues of the wires getting hot.)
I just must be careful to not power them ALL up at once as this might cause an overload spike and trip the breaker.

Thanks a lot!

What would you recommand for the heat removal? And yeah I currently have 2 miners running, but i wanted to install some more, the garage is big

For 10 miners? A very high CFM exhaust fan. 2500 CFM or so at least. Then you'll want a way to draw in fresh air, if you have windows you can use one as an intake and one as exhaust if they are not too close together and not too small.

I run 100 miners across (5) 200amp panels.  Each panel has (10) 20amp 220V breakers.  Each breaker goes to a a dual 220V 15amp receptacle.  Each receptacle powers two miners.

Please note that a 15 amp dual receptacle is rated at 15 amps per plug location.  Of course, the wiring needs to handle the total intended load.

At 220V, each miner would suck 6.86 Amps, so 13.72 amps per receptacle, or 68.6% of each 20 amp breaker - nicely under the 80% continuous load rule.

(10) such circuits pull 137.2 amps for a 68.6% total load on the 200 amp mains.  In reality, I have a couple of 15A 110V circuits on the panels for LED lighting, network gear, etc., but that doesn't affect the numbers much, and the panel as a whole is still nicely below the 80% rule.

I would suggest having a 100amp sub-panel with (5) 20 amp 220V breakers installed.  That would provide you power for your 10 machines, presuming you have ~70amps to spare (possibly a problem in the summer if you have an all electric house).

I presume you are prepared for your electric bill once these are running?  Rough math:  1.5Kw/miner/hour, 15Kw/10 miners/hour, 24 hours a day, 30 days a month, 10 cent/kw = $1080/month to power these...

Each S9 will pull about 300 CFM, so (10) would require 3000 CFM.  One exhaust fan of that rating or higher and a 10 square foot+ screened in opening should do it.  Anything much smaller on that opening and you will need both an intake and exhaust powered fan or risk back pressure issues,

Note that if you allow the intake and exhaust air to mix from the miners, your likely going to need more air flow.  Ideally you should never let the air from the two sides of the miner mix.

That's good advice. I prefer to contain the hot air and send it out the window. That way I get to work on the cool side.

Really if the exhaust hole and containment is large enough, you will not need a fan. Fans are for forcing air through a too small aperture.

The intake side is a different story, since you'll need to pull air through a filter. 

In regards to handling your intake and discharge air, you have a few options. One is to create a wind tunnel that your ten miners and power supplies will sit in with the discharge of these units about 3 feet away from your main fan discharging air out of the space. Making sure that you have a filtered opening elsewhere in the garage to allow the free flow of ambient temperature air for cooling.

The other option uses the same idea but with a mini room built for you discharge air. The miners and power supplies themselves run through the wall with intake on one side and discharge on the other. You still need to have a discharge fan set up to remove the air from the hot side, and an adequate filtered opening to allow cooling air.

Without knowing what your garage has in regards to windows or air intakes it's hard to give you any more than theoretical ideas. Here is a link to an idea for the wind tunnel idea.

Not my idea just something I found useful once.

https://bitcointalk.org/index.php?topic=2156421.msg21619449#msg21619449

okay so question.  I am running several sets of 2 miner on 20 Amp Breakers.   12 gauge  wire.  No issues.

I am getting a few more miners soon, my breaker box is full.

So I see no issue my changing the 20 Amp Breakers to 30 Amp Breakers, and then putting 3 miners on each circuit, that is what I have read here.  

If this is the case, can I keep 12 gauge wire (will three miners work ok hooked up to a 30 Amp breaker running on 12 gauge wire?)  

Or do I need to go with 10 Gauge wire?   The distance from the outlet to the breaker box is less than 3 feet, very close..

Dumb question, I know 40 amp breakers are available, why not go with those, or best to keep the 30 amp?

Thank you!

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(Moderator's note: This post was edited by frodocooper to remove an unnecessarily quoted post.)

Length doesn't matter. haha

If you think about it, a fuse is very short yet it will burn in half when it's rated current is exceeded. Never, ever use a conductor under the size required for the protector.

I too ran out of positions in my panel. I just got several of those double breakers to consolidate my home loads onto fewer positions. So each single pole breaker has two output circuits. This opened up enough stab positions for me to install my 20A, 2-pole breakers. You have to buy two of those dual breakers to make room for one 2-pole breaker.

If you try to use 10-gauge wires they probably will not fit into your receptacles.

I'd suggest you either consolidate using dual breakers as described above or install a sub panel. I added a 125 amp sub panel once I grew past the original panel.

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(Moderator's note: This post was edited by frodocooper to trim the quote from mineintx.)

You size the wire to the breaker regardless of the load.

20A breaker 12GA wire
30A breaker 10GA wire

You also will need to install the correct outlet for the amperage as well.

Because it's all very short and I ASSume out in the open doing this correctly should be relatively easy or cheap if you pay an electrician.