Need help with voltages/amp output

[Minewell]

Hello!!

I’m in the process of setting up a mining facility and I am having a difficult time figuring a few things out.

To start, this will be powered by a natural gas generator that outputs 3 phase at 120/208. It has 12 reconnectable leads so the voltage can be changed in my understanding (to either 127/220, 120/240, 139/240, 220/380, or 277/480). Would any of these work? Preferably 120/208 or 120/240 due to retention of peak amperage output. 208v 3 phase delta would supposedly be great, but I’m not sure if 120/208 fits that bill?

Or would I HAVE to step down 277/480 to 415/240 via a transformer? 277/480 reduces my amp output by more than half, thus reducing the amount of mining units I could power or forcing me to step up to an even larger generator that produces enough amps at 480v, with both scenarios severely cutting into my cost efficiency. Or Would the transformer bump my amperage back up to the acceptable 240v level? The generator at question would be ideal because kW provided are well within range, but 480v produces a ridiculously low level of amps.

Many other miners are using natural gas generators to power a bank of ASIC miners so there has to be a good solution here.

[mikeywith]

277/480 reduces my amp output by more than half, thus reducing the amount of mining units I could power or forcing me to step up to an even larger generator

These U.S voltage ranges are as complicated as it gets, at least judging by how simple things are over here, but then the power laws are universal, which means the part quoted above is most likely WRONG!, at least the last part of it.

Higher voltage does mean fewer amps, but "current" aka amp unit here does not even matter. Regardless of the voltage power = power, your generator is rated by KVA for simplicity KVA is KW not accounting for the power factor.

So in other words, if your generator is rated at 100KVA, it will be able to output 80KW worth of power, if put at 220v then it translates to "363 amps", if it's at 110v then you times that by two and it becomes "726 amps" but that does NOT mean your generator magically generates more power at a lower voltage because 80KW is 80KW be at 220V or even 12V is irrelevant to the case in hand.


 I can't seem to understand the mess in these voltage ranges, but to give you a clue based on power generators where I live, there are two types of them.

1- Single-phase 220v (1L 1N), you get it as is, if it says 100KVA you get 100KVA from N and  L.

2- Three-Phase 380v (3L, 1N), you get 380v from every 2 L lines and 220v from every L and N, but then every phase (L and N) will be capped by 1/3 of the total capacity of the generator, so if you need to use the 3 phase generator on single-phase devices, you will end up with 3 outputs each is L and N and you must balance the load between them all since that could be a bit hard to achieve some people chose to change the connection and get single-phase output from the generator by sacrificing 1/3 of the KVA, which means changing 99KVA 3 phase gen to a single-phase will give you a max of 66KVA between 1 L and N.

Long story short, is that the VAST MAJORITY of miners need a SINGLE phase 220-240v, so discuss with your selection on the best setup to achieve this, also there are two members here who are really good in this field : NotFuzzyWarm and HagssFIN). hopefully they will chime in and give you some advice.

[DaveF]

Keep in mind most generators do not put out clean sine wave electricity. The output is usually noisy and a bit dirty till you put in power conditioners.
If you don't have clean power you can do real damage to the power supplies of the miners.

-Dave

[Minewell]

277/480 reduces my amp output by more than half, thus reducing the amount of mining units I could power or forcing me to step up to an even larger generator

These U.S voltage ranges are as complicated as it gets, at least judging by how simple things are over here, but then the power laws are universal, which means the part quoted above is most likely WRONG!, at least the last part of it.

Higher voltage does mean fewer amps, but "current" aka amp unit here does not even matter. Regardless of the voltage power = power, your generator is rated by VA for simplicity VA is KW not accounting for the power factor.

So in other words, if your generator is rated at 100KVA, it will be able to output 80KW worth of power, if put at 220v then it translates to "363 amps", if it's at 110v then you times that by two and it becomes "726 amps" but that does NOT mean your generator magically generates more power at a lower voltage because 80KW is 80KW be at 220V or even 12V is irrelevant to the case in hand.


 I can't seem to understand the mess in these voltage ranges, but to give you a clue based on power generators where I live, there are two types of them.

1- Single-phase 220v (1L 1N), you get it as is, if it says 100KVA you get 100KVA from N and  L.

2- Three-Phase 380v (3L, 1N), you get 380v from every 2 L lines and 220v from every L and N, but then every phase (L and N) will be capped by 1/3 of the total capacity of the generator, so if you need to use the 3 phase generator on single-phase devices, you will end up with 3 outputs each is L and N and you must balance the load between them all since that could be a bit hard to achieve some people chose to change the connection and get single-phase output from the generator by sacrificing 1/3 of the KVA, which means changing 99KVA 3 phase gen to a single-phase will give you a max of 66KVA between 1 L and N.

Long story short, is that the VAST MAJORITY of miners need a SINGLE phase 220-240v, so discuss with your selection on the best setup to achieve this, also there are two members here who are really good in this fieldNotFuzzyWarm and HagssFIN). hopefully they will chime and in and give you some advice.

I do follow what your saying mostly. My conundrum is the generator voltage and amp output, I understand that the power will stay the same regardless of voltage. Using an example of a 100 kW generator with a 350 amperage output and 400 amp circuit breaker: say I want to run 20 miners with a wattage and amp draw of roughly 3400 watts and 15 amps, respectively. The generator will run at 90 kW prime and my total watt draw is 68,000. That’s perfect with about 75% load capacity. The miners will draw 15 amps each so a total amp draw of 300 amps. Again that works great. OK looking good. Now this generator is setup at 120/208. Will this voltage work to power my bank of miners? If not, I have a number of other voltages I could reconfigure to due to the reconnectable leads. Each voltage will change the amp output, so I’m trying to maximize my miner count to my generator output. Ideally I would run 20 miners off this generator.

Or would I have to reconfigure the voltage to 277/480 and step down to 415/240 via a transformer? This scenario would drop my amp output to 150 (estimated) and I would only be able to run 10 miners and have to buy an expensive transformer to boot. This would make the entire endeavor inefficient and hurt my economics. I am trying to avoid this situation and maximize my amp output to the miners.

I have a number of possible voltage reconfigurations. I find it hard to believe that I will have to buy a transformer and run 480 voltage from my generator. How do people run ASIC miners from their household electricity? They are surely not jumping through all of these hoops and setting transformers to step up/down their voltage.

[mikeywith]

How do people run ASIC miners from their household electricity? They are surely not jumping through all of these hoops and setting transformers to step up/down their voltage.

At least 9 out of 10 houses on planet earth have 220 or 240v in any socket attached to the wall, so they just plug the end of the power cord and off to the races.

A few countries like the U.S use 120v and thus people will be limited to old gears that support 120v or they hire someone to set up a 220v line for them if possible.

Again.. you need 220 to 240 to run most miners, anything outside of that range will either cause you issues or in most cases just won't work.

[Minewell]

How do people run ASIC miners from their household electricity? They are surely not jumping through all of these hoops and setting transformers to step up/down their voltage.

At least 9 out of 10 houses on planet earth have 220 or 240v in any socket attached to the wall, so they just plug the end of the power cord and off to the races.

A few countries like the U.S use 120v and thus people will be limited to old gears that support 120v or they hire someone to set up a 220v line for them if possible.

Again.. you need 220 to 240 to run most miners, anything outside of that range will either cause you issues or in most cases just won't work.

Gotcha. Then I’m a bit perplexed as to why I’m told that my current/possible voltage configurations wouldn’t work. The generator can run 120/240 and 139/240. Neither of these would work?

See this article from Raptor Power Systems: https://raptorpowersystems.com/industries/crypto-mining

How would any generator be able to power any household item, yet wouldn’t be able to power a miner at any voltage configuration, even though the miner can be powered by household electric. It just doesn’t make much sense to me.

[mikeywith]

You will Likely be able to get this to work, but i don't understand the ranges you are talking about, can you post the datasheet of the generator you have?

[BitMaxz]

It would be better to read the manual of the ASIC miner you want to run with the generator. If it says 220-240v then focus on providing a 220-240v lower or more than that it can damaged your miner PSU. Sample s19 pro based on their specs it runs at 3250w ± 5% so you would need more than 20 amps wall outlet with 220-240v to run this miner if the generator could provide that then you can mine with s19 pro.

If you want to run them at 120v then you can but I believe you can only run one hashboard with this voltage output on that miner.

[NotFuzzyWarm]

Hello!!

I’m in the process of setting up a mining facility and I am having a difficult time figuring a few things out.

To start, this will be powered by a natural gas generator that outputs 3 phase at 120/208. It has 12 reconnectable leads so the voltage can be changed in my understanding (to either 127/220, 120/240, 139/240, 220/380, or 277/480). Would any of these work? Preferably 120/208 or 120/240 due to retention of peak amperage output. 208v 3 phase delta would supposedly be great, but I’m not sure if 120/208 fits that bill?

<snip>

Reading your replies, you are over thinking things: If you are in North America then using the taps for 120/240 is perfect, that is a 3-phase wye connection with a center neutral that is also the power ground point.

All the other taps are for international power compatibility. Biggest thing you want is the 240VAC phase-to-phase and 120V phase-to-neutral. The 120v is just for powering things like security & monitoring systems, lights, small equipment like a vacuum or small pressure blower for cleaning the miners from time to time.

Biggest thing to keep in mind is that the genset will be running 24x7x365: That means it must be rated for what is called Prime Power usage. Normal standby-rated gensets MUST be shut down and serviced every few days, for one thing to change the oil and filter, another is to replace the brushes that feed power to the rotor. Prime power gensets run for months before needing to be looked at and that is mainly just topping off the oil reservoir and changing the oil filters - both of which are done w/o/ shutting down.

[Minewell]

Reading your replies, you are over thinking things: If you are in North America then using the taps for 120/240 is perfect, that is a 3-phase wye connection with a center neutral that is also the power ground point.

All the other taps are for international power compatibility. Biggest thing you want is the 240VAC phase-to-phase and 120V phase-to-neutral. The 120v is just for powering things like security & monitoring systems, lights, small equipment like a vacuum or small pressure blower for cleaning the miners from time to time.

Thank you! What does the slash signify, ie 120 slash 240? Is that the same as household 240v electricity? Isn’t household electric 240v single phase, not 3 phase? And if I was recommended to run 415/240 3 phase, how does that differ from 120/240? Why would Raptor recommend I run 415/240?

[NotFuzzyWarm]

Again, are you in North America? For purposes of discussion we MUST know where you are operating because as Mikey said early on, different countries/regions have different power setups.

Ref https://en.wikipedia.org/wiki/Three-phase_electric_power and start at the section labeled 'Generation and distribution'. Again, you would use the wye connection setup which is 3x lines + 1 neutral. The miners go across any 2 lines with line-to-line giving (240v), aux services go line-to-neutral giving (120v).

120/240v etc means line-to-line voltage is 240VAC. The neutral is in the middle of the phases so phase-to-neutral voltage is 1/2 the line-to-line voltage or 120V.

Though you will not be using it, here is how NA does split-phase power
In NA household voltage is 120vac single phase BUT that is tapped off of 2 lines along with a neutral from the 3-phase grid in what is called a split-phase arraignment. That gives L1 to N = 120v, L2 to N = 120V, L1 to L2 = 240v with the 240v used to power large loads like ovens, electric dryers, and air conditioners.

No idea about Raptor or their reasoning other than it is decided by how they divide up the power. eg do they use line-to-line or line-to-neutral.

[Minewell]

Again, are you in North America? For purposes of discussion we MUST know where you are operating because as Mikey said early on, different countries/regions have different power setups.

Ref https://en.wikipedia.org/wiki/Three-phase_electric_power and start at the section labeled 'Generation and distribution'. Again, you would use the wye connection setup which is 3x lines + 1 neutral. The miners go across any 2 lines with line-to-line giving (240v), aux services go line-to-neutral giving (120v).

120/240v etc means line-to-line voltage is 240VAC. The neutral is in the middle of the phases so phase-to-neutral voltage is 1/2 the line-to-line voltage or 120V.

Though you will not be using it, here is how NA does split-phase power
In NA household voltage is 120vac single phase BUT that is tapped off of 2 lines along with a neutral from the 3-phase grid in what is called a split-phase arraignment. That gives L1 to N = 120v, L2 to N = 120V, L1 to L2 = 240v with the 240v used to power large loads like ovens, electric dryers, and air conditioners.

No idea about Raptor or their reasoning other than it is decided by how they divide up the power. eg do they use line-to-line or line-to-neutral.

Yes I am in North America. Ok thanks a ton for your help.