at what point is a person considered a "respectable" miner?

[DeathAndTaxes]

He used 12/3 as I recall...

I deleted my post above because it likely contains misinformation based on comment from a friend who is electrician. 

While 12 gauge wiring is good for 30A Section 240.4(D) limits branch circuits to 15A on 14 gauge, 20A on 12 gauge, 30A on 10 gauge.

Still you could switch to 240V 20A at some point in the future giving you 80%*20*240V = 3.8KW per drop.

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[rjk]

I saw somewhere that Facebook is using 277v PSUs to save even more energy somehow. Does anyone know where to get these PSUs, and how high of wattage they are available in? I have 480 3phase that works out to 277 phase-to-ground, and if its more efficient I should be using it.

Right now my 240v comes thru a transformer that does 480 --> 240 conversion, at who knows what efficiency. Skipping that would help even more.

[DeathAndTaxes]

I saw somewhere that Facebook is using 277v PSUs to save even more energy somehow. Does anyone know where to get these PSUs, and how high of wattage they are available in? I have 480 3phase that works out to 277 phase-to-ground, and if its more efficient I should be using it.

Right now my 240v comes thru a transformer that does 480 --> 240 conversion, at who knows what efficiency. Skipping that would help even more.

277V PSU won't do you any good if your mains are 480V to 240V.   I would imagine no transformer is involved you are simply supplied 2x 240V legs.

Given there are now 80-Plus Platinum PSU getting 93%+ efficiency at 75% load (and likely +2% higher @ 240V) there isn't much inefficiency left to trip away.

Google also had custom PSU built for their datacenter years ago but that was back when avg ATX PSU was 70% efficient.

[JWU42]

He used 12/3 as I recall...

12/2 with ground, or 12/3 with ground?

Now you are getting outside my knowledge base.  I thought I was doing well with knowing the whole 12/3 part 

[JWU42]

He used 12/3 as I recall...

I deleted my post above because it likely contains misinformation based on comment from a friend who is electrician. 

While 12 gauge wiring is good for 30A Section 240.4(D) limits branch circuits to 15A on 14 gauge, 20A on 12 gauge, 30A on 10 gauge.

Still you could switch to 240V 20A at some point in the future giving you 80%*20*240V = 3.8KW per drop.

Thanks D&T...

Then I would need to get "The Clamp" to measure wattage as the Killa-aWatt is worthless on 240V?

[DeathAndTaxes]

He used 12/3 as I recall...

I deleted my post above because it likely contains misinformation based on comment from a friend who is electrician.  

While 12 gauge wiring is good for 30A Section 240.4(D) limits branch circuits to 15A on 14 gauge, 20A on 12 gauge, 30A on 10 gauge.

Still you could switch to 240V 20A at some point in the future giving you 80%*20*240V = 3.8KW per drop.

Thanks D&T...

Then I would need to get "The Clamp" to measure wattage as the Killa-aWatt is worthless on 240V?

Correct.  Alternatively there are 240V devices which are similar to Kill-a-Watt.

http://cablesaurus.com/index.php?route=product/product&path=15&product_id=30

Cablesaurus sells one.  I have no idea how good it is.  

A good clampmeter that kind measure AC current accurately (often called "True RMS") is kinda expensive, >$140 ish.  DC only or AC/DC averaging meters are cheaper but aren't going to do you any good for measuring AC efficiency. 

So a good cheap kill-a-watt like meter for 240V it would be useful.

[Kluge]

I am wondering if it would have been better to do the 240V 30A thing -- didn't know any better at the time.

I had our electrician put in 4 20amp circuits (120V) two weeks ago.

Higher voltage gives you slightly better efficiency. I'm just about to switch, so I should get a good clamp meter so I can determine the change in the power usage.

If anyone's interested in some graphs.....

https://docs.google.com/viewer?a=v&q=cache:ukzeb9vRpNwJ:pqlit.eaton.com/ll_download_bylitcode.asp%3Fdoc_id%3D11366+&hl=en&gl=us&pid=bl&srcid=ADGEESje68l6FOYZ8zwk-4FqJnO9Dqf-9cDrP4StWMi1X7JJSuZtHEOjN6bTK8KoyjDgg8I1Rgy33ttjV8vvDDy9vtD2y-hIoeteutnkW-G9baV3q7VTtwY_hMOuIDvBJDKTKAnIgrQ7&sig=AHIEtbQNixyUn7sxvcECcb0bI4Z_6ZHJsg

Though it'd depend on the PSU, high-end PSU gains seem to be ~2-3%.

I spend ~$70.50/month (@~$.12/kWh) to power 6 5850s running on three rigs @~2GH/s. Assuming 2% efficiency gain, power savings per month would be ~$1.41/month. *12=$16.92/year - (Assuming a 3% efficiency gain, $25.38/year). Not sure this would be worth the time, space, and up-front cost unless you're running many rigs (or have electric appliances which'll run on 240v).

[rjk]

I saw somewhere that Facebook is using 277v PSUs to save even more energy somehow. Does anyone know where to get these PSUs, and how high of wattage they are available in? I have 480 3phase that works out to 277 phase-to-ground, and if its more efficient I should be using it.

Right now my 240v comes thru a transformer that does 480 --> 240 conversion, at who knows what efficiency. Skipping that would help even more.

277V PSU won't do you any good if your mains are 480V to 240V.   I would imagine no transformer is involved you are simply supplied 2x 240V legs.

Given there are now 80-Plus Platinum PSU getting 93%+ efficiency at 75% load (and likely +2% higher @ 240V) there isn't much inefficiency left to trip away.

Google also had custom PSU built for their datacenter years ago but that was back when avg ATX PSU was 70% efficient.

I have access to a panel on both sides of the transformer. I found the PSU I was looking for: http://opencompute.org/projects/power-supply/
It actually is autoranging from 180v to 305v, but optimal efficiency is at 277. According to the spec sheet, numbers are as follows:

>0.95 power factor and <10% THD with harmonics up to and including 40, at 277VAC RMS 50 or 60 HZ.
90% efficiency at 20% load, 95% at 50% load, and 91% at 100% load.

However the PSU is only 450 watts. The reasons for choosing 277VAC are:
a) Still only one phase to worry about - not two or three per PSU. Less wiring.
b) No 480 --> 240 VAC transformer losses. (Not sure how much efficiency loss there is, but I don't think the transformer could be any higher than 96-97% efficient. Mine is a 45Kva SquareD)
c) Smaller gauge wiring due to the higher voltage.

So it makes sense for datacenters with thousands of custom servers like FB and Google, but probably not much for the average miner.

[Inspector 2211]

like what gh level?

Like i am putting my first dedicated rig together.. aiming for 2.4gh..

need a bit more funding to put get more 5970s

You are a respectable miner if you have already tripped circuit breakers and/or contributed to global warming and/or got kicked out of your "mining office" by your commercial landlord.

The latter happened to me half a year ago.
3 day notice to vacate for breach of lease terms.
"The owner has seen the electrical bill of the entire office building DOUBLE, and he wants you out."
"Consider this your 3 day notice."

I had four mining rigs plugged into the 20 amp circuit of the left wall, and four mining rigs plugged into the 20 amp circuit of the right wall, drawing close to 40 amps total. Once I tried to print a document on the laser printer - when the laser printer heated up its toner filament, it caused the circuit breaker to trip.

Good times.

[DeathAndTaxes]

The reasons for choosing 277VAC are:
a) Still only one phase to worry about - not two or three per PSU. Less wiring.
b) No 480 --> 240 VAC transformer losses. (Not sure how much efficiency loss there is, but I don't think the transformer could be any higher than 96-97% efficient. Mine is a 45Kva SquareD)
c) Smaller gauge wiring due to the higher voltage.

Well "a" doesn't really matter.  If you home isn't 3 phase you aren't getting 3 phase anyways.

On "b" I think you are forgetting about the 480 -> 277 VAC transformer. Still transformers tend to be very efficient.  97%+ is certainly likely, 99%+ is possible.   Energy in = Energy out.  So all the energy on the 480 VAC side becomes 240 VAC or heat.  An inefficient transformer on a mains where it could be pulling 100 amps+ would quickly melt.  Some quick numbers.  The transformer is rated at 45KVA so at 5% inefficiency and peak load ~2.5KW would be converted into heat.  Heat output on the transformer would be more than 10x 5970s.

Optimally the best thing for you would be a high efficiency 5KW 480VAC to 12VDC powersupply.  You could power an entire rack of GPUs.    Then just run the low wattage mixed voltage components off some low wattage ATX PSU units.  Now if you found and rigged that you might be a serious miner.

[eviltt]

like what gh level?

Like i am putting my first dedicated rig together.. aiming for 2.4gh..

need a bit more funding to put get more 5970s

You are a respectable miner if you have already tripped circuit breakers and/or contributed to global warming and/or got kicked out of your "mining office" by your commercial landlord.

The latter happened to me half a year ago.
3 day notice to vacate for breach of lease terms.
"The owner has seen the electrical bill of the entire office building DOUBLE, and he wants you out."
"Consider this your 3 day notice."

I had four mining rigs plugged into the 20 amp circuit of the left wall, and four mining rigs plugged into the 20 amp circuit of the right wall, drawing close to 40 amps total. Once I tried to print a document on the laser printer - when the laser printer heated up its toner filament, it caused the circuit breaker to trip.

Good times.

hahaha.. i thought of doing that renting some space at an executive office building.. only concern i have is that they tend to turn the AC off on the weekends

[JWU42]

He used 12/3 as I recall...

I deleted my post above because it likely contains misinformation based on comment from a friend who is electrician.  

While 12 gauge wiring is good for 30A Section 240.4(D) limits branch circuits to 15A on 14 gauge, 20A on 12 gauge, 30A on 10 gauge.

Still you could switch to 240V 20A at some point in the future giving you 80%*20*240V = 3.8KW per drop.

Thanks D&T...

Then I would need to get "The Clamp" to measure wattage as the Killa-aWatt is worthless on 240V?

Correct.  Alternatively there are 240V devices which are similar to Kill-a-Watt.

http://cablesaurus.com/index.php?route=product/product&path=15&product_id=30

Cablesaurus sells one.  I have no idea how good it is.  

A good clampmeter that kind measure AC current accurately (often called "True RMS") is kinda expensive, >$140 ish.  DC only or AC/DC averaging meters are cheaper but aren't going to do you any good for measuring AC efficiency. 

So a good cheap kill-a-watt like meter for 240V it would be useful.

Good news for me is the miners are in the basement in the same room as the box (i.e., not much to run).  Might have him put in the 240v 30A right beneath the box and then i have the 12 foot cord from the PDU to my advantage...

[Joshwaa]

If yall are in south florida PM me I have a location that I let miners put their machines. I charge 1BTC for every  10BTC your miner generates. Currently I am at 7.6GHash and I have two clients (Friends, lol) that are at 1GHash each. If I get enough people to mine at the location might do a local pool.  I would like as much input about this as possible.

[Mousepotato]

If you bought four 7970s and still can't maintain a 1.00 KDR in BF3/MW3, you might be a miner.

[Inspector 2211]

If yall are in south florida PM me I have a location that I let miners put their machines. I charge 1BTC for every  10BTC your miner generates. Currently I am at 7.6GHash and I have two clients (Friends, lol) that are at 1GHash each. If I get enough people to mine at the location might do a local pool.  I would like as much input about this as possible.

This may be a very good deal for miners with power-hogging graphics cards, such as the HD 6990, but not a good deal at all for FPGA miners.

[rjk]

On "b" I think you are forgetting about the 480 -> 277 VAC transformer. Still transformers tend to be very efficient.  97%+ is certainly likely, 99%+ is possible.   Energy in = Energy out.  So all the energy on the 480 VAC side becomes 240 VAC or heat.  An inefficient transformer on a mains where it could be pulling 100 amps+ would quickly melt.  Some quick numbers.  The transformer is rated at 45KVA so at 5% inefficiency and peak load ~2.5KW would be converted into heat.  Heat output on the transformer would be more than 10x 5970s.

No, there isn't a transformer because the delta circuit is 277 phase-to-ground but is 480 phase to phase I think you might have been confusing 277 with 240

True about the efficiency though - when the industrial machines in the same building are running at full blast, the transformer is uncomfortably warm on top, but not so hot you would burn yourself instantly. So yes probably better than 97%.

[chungenhung]

Consider I'm living in a country where -20 is common in January.

-If you can heat your feets with your mining rig, you're just starting.
-If you can heat a room with your mining rig, you have a nice hobby.
-If you're starting to save on heating because you heat the house, you're serious dude.
-If you can heat a whole 4-story house, with people keeping the windows open because it's too hot, and having the oil company giving you refunds on your heating bill, I believe it is the point where you are "respectable".

seriously, i have only had to turn on the heat once for this winter, and it's because the internet was down!

[Inspector 2211]

hahaha.. i thought of doing that renting some space at an executive office building.. only concern i have is that they tend to turn the AC off on the weekends

Actually, an office AC can only get rid of maybe 1000 W without the room getting uncomfortably hot - in the old office there were two window panes that opened (left and right) and I had all 4 mining rigs on the left and 4 on the right and had cardboard ducts with fans to blow the hot air right out for the windows. And still the room was like a sauna.

In my current office, unfortunately the window does not open at all, and I have only 3 rigs in operation, four HD 5830 each, and once again it is like a sauna and I always take my shirt off when I'm there.

So, now you know why I'm increasingly interested in FPGA mining.

[Joshwaa]

Consider I'm living in a country where -20 is common in January.

-If you can heat your feets with your mining rig, you're just starting.
-If you can heat a room with your mining rig, you have a nice hobby.
-If you're starting to save on heating because you heat the house, you're serious dude.
-If you can heat a whole 4-story house, with people keeping the windows open because it's too hot, and having the oil company giving you refunds on your heating bill, I believe it is the point where you are "respectable".

seriously, i have only had to turn on the heat once for this winter, and it's because the internet was down!

Wish I had yall's problem. I have only been able to shut off my A/C for one day this Winter.

[eviltt]

Consider I'm living in a country where -20 is common in January.

-If you can heat your feets with your mining rig, you're just starting.
-If you can heat a room with your mining rig, you have a nice hobby.
-If you're starting to save on heating because you heat the house, you're serious dude.
-If you can heat a whole 4-story house, with people keeping the windows open because it's too hot, and having the oil company giving you refunds on your heating bill, I believe it is the point where you are "respectable".

seriously, i have only had to turn on the heat once for this winter, and it's because the internet was down!

Wish I had yall's problem. I have only been able to shut off my A/C for one day this Winter.

this is how i feel being in phoenix, power isnt badly priced... but AC will be working overtime! haha

and when its 125 outside not going to get much cooling going out there haha