100A 120/240 Electrical panel; how many miners can I use?

[maxilauri]

I am looking specifically at miners that pull 1300W from the wall. GPU miners.

Each miner is on a dedicated circuit. Electrician installed 20 circuit, each rated 15A.

The electrical panel is 100A, which is all code allows here. 120/240 typical but I could only install 120V lines in my garage due to regulations.

Each of my miner pulls 1300W, tested with kill-a-meter at source. How many of these miners can I run on that panel?

Thank you.

[HagssFIN]

That will be one miner per 15 Amp circuit.

I've never understood why the US uses 110V line to neutral voltage. You have so little power capacity with the 15 A, reasonable price wire cauge circuits.

230V line to neutral here in Finland is much better.

[DaveF]

OP:
Amps = Watts/Volts
So 1300W / 120 V = 10.83 Amps per rig with no loss due to wire resistance / PS inefficacy 13A is a more reasonable number to look at.
100A panel / 13A per circuit is 7.7 so going full tilt with minimal loss figure 7 rigs max on 100A


HagssFIN: US is 110V just do the fact that when places here in the US were 1st getting power bulbs worked at 100V more or less so that is what they gave people. Once better bulbs came out it was too late to really change unless you wanted to scrap / re-do large portions of already existing infrastructure. When Europe started getting AC power setup a few years later better bulbs and other things were already available so 220 it was. (Source: Something I saw on the history channel years ago)

-Dave

[HagssFIN]

@DaveF Thanks for the history story, and for mentioning the total 7 rigs with that panel. I forgot to say it.

[maxilauri]

That will be one miner per 15 Amp circuit.

So 20 miners total? Electrician installed 20 lines

[64dimensions]

I'm not a professional engineer, so check with the proper experts.

This is what I have done as a US mining hobbyist.


1) You cannot overload your electrical panel. So the limit is 100 A. This is what unusual about mining in that you will be needing power 100% 0f the time. A panel may have more circuits then capacity but in your case you are limited to 100A

2) This 100A will flow through circuit breakers. Circuit breakers are derated by code to 80% of their rating.

3) A 120v circuit uses a 15A breaker. The total available power per circuit is 1800W x .8 = 1440 watts

4) So 100A/15A = 6.67 systems

1440 W is on the edge

One thing about mining is that you can to some degree adjust the power draw down. If you are a gpu miner you can shuffle cards around operate them at a lower power for the most hash per 100A.

[HagssFIN]

That will be one miner per 15 Amp circuit.

So 20 miners total? Electrician installed 20 lines

Did you see that I said 7 rigs in my next message,
just like DaveF said.

7 rigs is the max. in your setup, with that panel, 120V, and those rigs you described.

The rest 13x circuits will remain empty, because you have already maxxed the 100A panel.
I don't know what your electrician has been thinking (or if he even put any thought in to it) when he created that system with 20x 15A circuit, with 100A panel.

You were also explained the math here, so I don't know how you think you could put 20 rigs there.

[maxilauri]

I'm not a professional engineer, so check with the proper experts.

This is what I have done as a US mining hobbyist.


1) You cannot overload your electrical panel. So the limit is 100 A. This is what unusual about mining in that you will be needing power 100% 0f the time. A panel may have more circuits then capacity but in your case you are limited to 100A

2) This 100A will flow through circuit breakers. Circuit breakers are derated by code to 80% of their rating.

3) A 120v circuit uses a 15A breaker. The total available power per circuit is 1800W x .8 = 1440 watts

4) So 100A/15A = 6.67 systems

1440 W is on the edge

One thing about mining is that you can to some degree adjust the power draw down. If you are a gpu miner you can shuffle cards around operate them at a lower power for the most hash per 100A.

Times two, so 13 miners. 14 as I am only taking 11-12A from each circuit?

[FP91G]

I am calculating in a different way
100A*120V=13200 Watt
I will design 12 mining farms with an electricity consumption of no more than 900-950 watts or 6 mining farms with an energy consumption of 2 kilowatts
And then for these farms I will select wires and circuit breakers

[maxilauri]

That will be one miner per 15 Amp circuit.

So 20 miners total? Electrician installed 20 lines

Did you see that I said 7 rigs in my next message,
just like DaveF said.

7 rigs is the max. in your setup, with that panel, 120V, and those rigs you described.

The rest 13x circuits will remain empty, because you have already maxxed the 100A panel.
I don't know what your electrician has been thinking (or if he even put any thought in to it) when he created that system with 20x 15A circuit, with 100A panel.

You were also explained the math here, so I don't know how you think you could put 20 rigs there.

Well 120V * 100A * 2 poles =24,000W

Let's go 80% max load to be safe. Round it to 20,000W

20,000/1300W =15.38

Lets round it up to 16 as miners dont all pull 1300.

[philipma1957]

That will be one miner per 15 Amp circuit.

So 20 miners total? Electrician installed 20 lines

Did you see that I said 7 rigs in my next message,
just like DaveF said.

7 rigs is the max. in your setup, with that panel, 120V, and those rigs you described.

The rest 13x circuits will remain empty, because you have already maxxed the 100A panel.
I don't know what your electrician has been thinking (or if he even put any thought in to it) when he created that system with 20x 15A circuit, with 100A panel.

You were also explained the math here, so I don't know how you think you could put 20 rigs there.

Well 120V * 100A * 2 poles =24,000W

Let's go 80% max load to be safe. Round it to 20,000W

20,000/1300W =15.38

Lets round it up to 16 as miners dont all pull 1300.

 a nice try on your part.

it all depends on the main breakers.


I hove 2 hots and a ground coming in.

each carry 120 volts and each are attached to a 150amp breaker as I have 150 amp service.

but the breaker is tied together. 

So the question is do you trip at 150+150 = 300 amps

or do you trip at 150 amps

in your case you are saying the 100 amp breaker is not linked

so your service is more like 100+100 = 200 at 120.

BTW. lets say the main breaker works as you say.

110 x 200 x .80 = 17600 /1300 = 13.5 rigs

or 6 on each pole

assuming that the mains will work like you think it works.

ie 100+100 =200 total
vs 100

using 110 is better than 120 since  voltage sag happens in hot months.

Also make very sure you have this balanced and the loads are on each pole the same.

good luck as I think it should be interesting to see if you 100 amp breaker handles 100 + 100 = 200 amps.

[maxilauri]

That will be one miner per 15 Amp circuit.

So 20 miners total? Electrician installed 20 lines

Did you see that I said 7 rigs in my next message,
just like DaveF said.

7 rigs is the max. in your setup, with that panel, 120V, and those rigs you described.

The rest 13x circuits will remain empty, because you have already maxxed the 100A panel.
I don't know what your electrician has been thinking (or if he even put any thought in to it) when he created that system with 20x 15A circuit, with 100A panel.

You were also explained the math here, so I don't know how you think you could put 20 rigs there.

Well 120V * 100A * 2 poles =24,000W

Let's go 80% max load to be safe. Round it to 20,000W

20,000/1300W =15.38

Lets round it up to 16 as miners dont all pull 1300.

 a nice try on your part.

it all depends on the main breakers.


I hove 2 hots and a ground coming in.

each carry 120 volts and each are attached to a 150amp breaker as I have 150 amp service.

but the breaker is tied together. 

So the question is do you trip at 150+150 = 300 amps

or do you trip at 150 amps

in your case you are saying the 100 amp breaker is not linked

so your service is more like 100+100 = 200 at 120.

BTW. lets say the main breaker works as you say.

110 x 200 x .80 = 17600 /1300 = 13.5 rigs

or 6 on each pole

assuming that the mains will work like you think it works.

ie 100+100 =200 total
vs 100

using 110 is better than 120 since  voltage sag happens in hot months.

Also make very sure you have this balanced and the loads are on each pole the same.

good luck as I think it should be interesting to see if you 100 amp breaker handles 100 + 100 = 200 amps.

Thx!!!

[HagssFIN]

So it was unclear to me if two phases are available at the panel. Then you could connect 10x 15A circuits to phase L1 and other 10x 15A circuits to phase L2.

You would have power capacity for 14 rigs in 14 circuits.
6 circuits would remain un-used because the panel is maxxed.

Maybe I should drop out from the conversation so that I don't mess this any more. The ANSI standard world is a bit weird to me.

[maxilauri]

So it was unclear to me if two phases are available at the panel. Then you could connect 10x 15A circuits to phase L1 and other 10x 15A circuits to phase L2.

You would have power capacity for 14 rigs in 14 circuits.
6 circuits would remain un-used because the panel is maxxed.

Maybe I should drop out from the conversation so that I don't mess this any more. The ANSI standard world is a bit weird to me.

You messed nothing up, I wasn't clear. I won't lie, I know nothing about electrical.

My electrician told me something about "both phases cancelling each other out" and "0A" and "electricity is a sin wave and they cancel each other" and I just got lost >.<

14 rigs it is. Thanks guy, I will leave this up if other people have that question in the future!

[philipma1957]

maybe 12 not 14 in hot summer months.

[DaveF]

The issue is we tend to run with what we know for where we are.
Where I live I can have a 100A singe phase run to my garage, or any other run that is outside of my main panel. Nothing else. So that is what I went with what is here.
If you can have something different then that in a residential setting then yes the answer will be different. I also assumed garage was a home garage not a commercial one.

@maxilauri Also, don't just listen to what is said here. talk with more then one local licensed electrician. Some may do things that are not up to local code and come back to bite YOU later. Even if your State / county / city allows something a local town might not.

-Dave

[philipma1957]

The issue is we tend to run with what we know for where we are.
Where I live I can have a 100A singe phase run to my garage, or any other run that is outside of my main panel. Nothing else. So that is what I went with what is here.
If you can have something different then that in a residential setting then yes the answer will be different. I also assumed garage was a home garage not a commercial one.

@maxilauri Also, don't just listen to what is said here. talk with more then one local licensed electrician. Some may do things that are not up to local code and come back to bite YOU later. Even if your State / county / city allows something a local town might not.

-Dave

good point.

my street transformer shared with me and my neighbors.  sends me

a ground
a hot 1
a hot 2

hot 1 is about 121.0 in winter low demand

hot 2 is about 121.7 in winter low demand

and if I wire 240  I go to 242.7

every year I drop as low as 237 and go as high as 244.

I never ran enough power to trip my mains.