120 or 240 volt?

[TTravis]

I have an evga 1300 an d noticed that it's input voltage range is 11-240v.  I am using this to power 3 S3's.

I am wanting to set this up in a workshop that has an unused 240v outlet.  I also have 120v available.

Is there an advantage or disadvantage to using 240 volt rather than 120 volt.

Looking at the equation p = i / e, I would not think it matters.

Does 240 volt put half the amps on the line?  Is this practical?

Thanks,

Tom

[SaltySpitoon]

It depends on your home's electrical typically based on the country you live in. In the US is 120V, but you would have to look it up by country, as I'm not sure what each country uses.

So assuming you haven't done a custom wiring job, use what your house supports. It will cause issues if you use the wrong voltage. That said, 240V has a higher watt output potential, since watts = Voltage x Amperage, so if you have a standard 15Amp 120V panel (US Standard for non appliances) it is capable of outputting 1800W. If it was 240V it would be capable out outputting 3600W.

[Marvell1]

It depends on your home's electrical typically based on the country you live in. In the US is 120V, but you would have to look it up by country, as I'm not sure what each country uses.

So assuming you haven't done a custom wiring job, use what your house supports. It will cause issues if you use the wrong voltage. That said, 240V has a higher watt output potential, since watts = Voltage x Amperage, so if you have a standard 15Amp 120V panel (US Standard for non appliances) that is capable of outputting 1800W. If it was 240V it would be capable out outputting 3600W.

bit misleading here ...

240V would pretty much be 30 amp and over

so actually output would be 7200W

240V is more efficient for circuits running 24-7 your would save 1-3% power use on 240V as well so 240V is ALWAYS better

[TTravis]

I am in the US.

[notlist3d]

It depends on your home's electrical typically based on the country you live in. In the US is 120V, but you would have to look it up by country, as I'm not sure what each country uses.

So assuming you haven't done a custom wiring job, use what your house supports. It will cause issues if you use the wrong voltage. That said, 240V has a higher watt output potential, since watts = Voltage x Amperage, so if you have a standard 15Amp 120V panel (US Standard for non appliances) that is capable of outputting 1800W. If it was 240V it would be capable out outputting 3600W.

bit misleading here ...

240V would pretty much be 30 amp and over

so actually output would be 7200W

240V is more efficient for circuits running 24-7 your would save 1-3% power use on 240V as well so 240V is ALWAYS better

Are you saying out of a single 240 you can power 7200 watts of miners?

[TTravis]

One circuit is breaker is marked "mill" and the other "lathe".  I have always just kept the breakers turned off.

Both mill and lathe have double 20A breakers, so how many watts does that give me on each circuit?  9600?

Since I am not use to working with 240v and have appreciation for the danger, I will have an electrician hook
it all up for me.

Thanks,

Tom

[philipma1957]

One circuit is breaker is marked "mill" and the other "lathe".  I have always just kept the breakers turned off.

Both mill and lathe have double 20A breakers, so how many watts does that give me on each circuit?  9600?

Since I am not use to working with 240v and have appreciation for the danger, I will have an electrician hook
it all up for me.

Thanks,

Tom

go 240volt look into server psu's

https://bitcointalk.org/index.php?topic=985163.0


the 850watt hp at 120 = 1000watt at 240 and is really cheap-------these are only 55 a kit.

the 1000 watt intel at 120 = 1200 watt at 240 not as cheap.

https://bitcointalk.org/index.php?topic=622783.0

[Finksy]

240V is superior for efficiency.  A double 20A breaker of 240V is still just 20A (it is 2x 20A circuits of 120V combined, that is typically how 240V circuits on panels work).  But 20A at 240V is double the watts of 20A @ 120V.

240V x 20A = 4,800W, so 2x separate 240V 20A circuits would give you 9,600W. Edit: As dropt mentioned, circuits are not meant to be run greater than 80% load continuously.

Going 240V also gives you access to these badass PSU's: https://bitcointalk.org/index.php?topic=966135.0

[dropt]

One circuit is breaker is marked "mill" and the other "lathe".  I have always just kept the breakers turned off.

Both mill and lathe have double 20A breakers, so how many watts does that give me on each circuit?  9600?

Since I am not use to working with 240v and have appreciation for the danger, I will have an electrician hook
it all up for me.

Thanks,

Tom

240*20*0.8 = 3,840.   So you can safely run 3,840W of gear 24/7 on your 20A@240V circuit assuming that the wiring in the walls is of the required gauge.

[Prelude]

If you can run 240v, do it. Any serious miner will run his hardware on 240v, nothing but advantages.

[Marvell1]

One circuit is breaker is marked "mill" and the other "lathe".  I have always just kept the breakers turned off.

Both mill and lathe have double 20A breakers, so how many watts does that give me on each circuit?  9600?

Since I am not use to working with 240v and have appreciation for the danger, I will have an electrician hook
it all up for me.

Thanks,

Tom

240*20*0.8 = 3,840.   So you can safely run 3,840W of gear 24/7 on your 20A@240V circuit assuming that the wiring in the walls is of the required gauge.

F that I max out my 30 amp breakers at 6800 watts or so , the cables are not even warm

that's 80% rule is really meant for 20 to 15 amp wiring that is far far inferior to 30 amp wiring.  30 amp cables are almost a half inch thing you can max them out at 90% load pretty safely

[philipma1957]

One circuit is breaker is marked "mill" and the other "lathe".  I have always just kept the breakers turned off.

Both mill and lathe have double 20A breakers, so how many watts does that give me on each circuit?  9600?

Since I am not use to working with 240v and have appreciation for the danger, I will have an electrician hook
it all up for me.

Thanks,

Tom

240*20*0.8 = 3,840.   So you can safely run 3,840W of gear 24/7 on your 20A@240V circuit assuming that the wiring in the walls is of the required gauge.

F that I max out my 30 amp breakers at 6800 watts or so , the cables are not even warm

that's 80% rule is really meant for 20 to 15 amp wiring that is far far inferior to 30 amp wiring.  30 amp cables are almost a half inch thing you can max them out at 90% load pretty safely

perhaps you have 40 amp gauge in your 30 amp breaker. which by your description of thickness sounds very possible.

[dropt]

One circuit is breaker is marked "mill" and the other "lathe".  I have always just kept the breakers turned off.

Both mill and lathe have double 20A breakers, so how many watts does that give me on each circuit?  9600?

Since I am not use to working with 240v and have appreciation for the danger, I will have an electrician hook
it all up for me.

Thanks,

Tom

240*20*0.8 = 3,840.   So you can safely run 3,840W of gear 24/7 on your 20A@240V circuit assuming that the wiring in the walls is of the required gauge.

F that I max out my 30 amp breakers at 6800 watts or so , the cables are not even warm

that's 80% rule is really meant for 20 to 15 amp wiring that is far far inferior to 30 amp wiring.  30 amp cables are almost a half inch thing you can max them out at 90% load pretty safely

Congratulations!  Just because you choose to take risks outside what is fairly common across electrical building codes doesn't mean you should be actively suggesting people do the same.  Further, the 80% rule has to do with continuously loaded circuits and has nothing to do with the CB's amperage.  I'd also like to know what you're basing your assumptions on when you state that  20A to 15A wiring is far inferior to 30A wiring.  I'm guessing by your logic "60A wiring" is better than 30A wiring, so why aren't we all just using 60A wires for everything?  Not to mention there is no such thing as 15A, 20A, or 30A wiring.

I don't mean to be an asshole but improper wiring can cause fire and may lead to loss of property, and in some cases loss of life.   Suggestions should always be made following standard guidelines (such as 80% rule) and leave overloading to the end user's full personal discretion.

[TTravis]

I won't overload the line.  So far all I have is 1 antminer s4 and 3 antminer s3's.
I hope to get the s3's up and going today.  Still waiting on the s4 to arrive.  I will wait
to see what/if profit I turn at .075/kwh and see if I buy more equipment.

I'll take a close look at what gage wire is coming off that double 20A breaker.  Knowing the guy
who built this house, it is probably one better than it needs to be.

I have 400A service, 200 of which is just for the workshop, so I think I am in good shape.

Has anyone looked at the power phase of the evga 1300 or psu or antminer s4?
I don't know if that is something I should look into, or is pf corrected in the design
to reach their efficiency?

Any suggestions on rigging up a 240v power strip so I don't have to change power cords?

[dropt]

I won't overload the line.  So far all I have is 1 antminer s4 and 3 antminer s3's.
I hope to get the s3's up and going today.  Still waiting on the s4 to arrive.  I will wait
to see what/if profit I turn at .075/kwh and see if I buy more equipment.

I'll take a close look at what gage wire is coming off that double 20A breaker.  Knowing the guy
who built this house, it is probably one better than it needs to be.

I have 400A service, 200 of which is just for the workshop, so I think I am in good shape.

Has anyone looked at the power phase of the evga 1300 or psu or antminer s4?
I don't know if that is something I should look into, or is pf corrected in the design
to reach their efficiency?

Any suggestions on rigging up a 240v power strip so I don't have to change power cords?

EVGA, along with most new PSUs have internal PFC.   As for the power bar, what socket is the 20A/240V circuit using?

[sidehack]

Hey, don't overlook the guys that basically started the server PSU breakout board industry for consumer miners. We still have some stuff worth looking at.
https://bitcointalk.org/index.php?topic=940317.0


Any large PSU worth anything will have active PFC, which typically gives you a power factor of .99 or better. That's one of the reasons why efficiency is better with 240V, because active PFC is a boost converter that always drives current proportional to line voltage into a >300V DC bus. If the line voltage is already getting into that neighborhood it doesn't have to work as hard to push the power uphill. Also, as mentioned, currents are reduced for the same amount of power consumed, which resistive loads (from wiring and such) are proportional to current squared - meaning if you halve your current you quarter your resistive losses. Another benefit not always directly intended is load balancing. Your house's mains feed transformer will have two 120V legs, and drawing different amounts of current from each leg is hard on the utility system so hooking up high-demand machinery to 240 will mean its current is being pulled from each phase equally.

[Prelude]

One circuit is breaker is marked "mill" and the other "lathe".  I have always just kept the breakers turned off.

Both mill and lathe have double 20A breakers, so how many watts does that give me on each circuit?  9600?

Since I am not use to working with 240v and have appreciation for the danger, I will have an electrician hook
it all up for me.

Thanks,

Tom

240*20*0.8 = 3,840.   So you can safely run 3,840W of gear 24/7 on your 20A@240V circuit assuming that the wiring in the walls is of the required gauge.

F that I max out my 30 amp breakers at 6800 watts or so , the cables are not even warm

that's 80% rule is really meant for 20 to 15 amp wiring that is far far inferior to 30 amp wiring.  30 amp cables are almost a half inch thing you can max them out at 90% load pretty safely

Please don't talk out of your ass. The 80% rule applies to all wiring. It's a safety code, and it shouldn't be ignored.

That being said, I have run 30A 240V circuits at 100% load for months at a time. Why? Because I wired everything myself and I know I used quality hardware everywhere with everything installed properly. While the wire gets warm during the hotter summer days, it's not an issue. The real issue is with the breaker, going over 24A on it for extended periods will cause premature wear from the stress. They heat up significantly at 100% continuous load, and eventually start arcing and fail. You DO NOT want a bad breaker, and that's why I advise following the 80% rule in general.

[Marvell1]

This thread is actually in the wrong forum actually.

I'm not talking out of my ass dummy , if you have your 30Amp breakers properly wired to a modern panel you can run them close to 90% load with no problems
some people even run then 100% load.  You would expect the breakers to be slightly warm with continous load but

if you are not sure on your wiring get an inspector or run them below max better safe than sorry.

If my wires were warm to touch I would definitely not run that much load your setup is a disaster waiting to happen.

and read my post again I never said i run at 100% load , thats stupid

[MrTeal]

https://books.google.ca/books?id=RCPHBgAAQBAJ&pg=PA55&lpg=PA55&source=bl&ots=BRuAEs_Zz7&sig=c52zuPv10XWkYAnRg3Bck6uE11A&hl=en&sa=X&ei=nvoSVbn5Ho_SoATCjIDADg&ved=0CDMQ6AEwAw#v=onepage&q&f=false

Where a branch circuit supplies continuous loads or any combination of continuous and noncontinuous loads, the rating of the overcurrent device shall not be less that the noncontinuous load plus 125 percent of the continuous load.

It's not a rule of thumb, it's code that the breaker has to be oversized 25% for continuous loads. If you have a nice thermal camera, try pulling 30A from the 30A breaker and 10 gauge wire (or 60A from a 6 gauge wire) and look at how hot the wire and breaker get. Yes they work, but it's against code and dangerous especially if you have multiple lines like that in the same panel.

[Prelude]

This thread is actually in the wrong forum actually.

I'm not talking out of my ass dummy , if you have your 30Amp breakers properly wired to a modern panel you can run them close to 90% load with no problems
some people even run then 100% load.  You would expect the breakers to be slightly warm with continous load but

if you are not sure on your wiring get an inspector or run them below max better safe than sorry.

If my wires were warm to touch I would definitely not run that much load your setup is a disaster waiting to happen.

and read my post again I never said i run at 100% load , thats stupid

  Yes, you're right and everyone else is wrong. Carry on, and please post pictures when the weakest link in your circuit fails.