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"Tinyboxes finally have a buy it now button"

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Re: "Tinyboxes finally have a buy it now button"

#131

Post by bombela »

amluto wrote: post #112
bombela wrote: post #59

Earlier quoted context omitted.

You can feed a US outlet the split phase 240V and get two 120V@20A each. It used to be done in kitchens in the US, back when appliances were power hungry. I have done so in my workshop for the same reason. Houses are wired in split phase 240V, with the neutral in the middle. That is, you have two opposite 120V phases, around the same neutral. This is a clever way to double the power, while adding a single wire. In th…

Skip the Y hack and do it in style, legally! https://store.leviton.com/products/duplex-receptacle-outlet-...

I am aware of this. But then I have a single 120@20 vs a single 240@20.

With my setup I have 2×120@20 always available, and 240@20 for the occasional welding.

I could assign a different 120 phase to every other outlet but then I would need some clear identification.

The two phases are assigned to the top and bottom outlets the same way all around the shop. If I need to run two high amperage machines, I only have to remember to use one bottom and one top outlet.

Re: "Tinyboxes finally have a buy it now button"

#132

Post by bombela »

amluto wrote: post #111
oasisbob wrote: post #97

Earlier quoted context omitted.

GFCI requirements will interfere with the legality of many modern-day multi-wire branch circuit plans, yeah?

You can get a two-pole GFCI breaker for this purpose. The prices are a bit silly.

two poles breakers, 2×120V@20A, $USD:

    - $20
    - GFCI, $115
    - GFCI + AFCI, $115
Yes it is expensive, but it can also save your life.

Re: "Tinyboxes finally have a buy it now button"

#133

Post by bombela »

mindslight wrote: post #105
bombela wrote: post #59

Earlier quoted context omitted.

You can feed a US outlet the split phase 240V and get two 120V@20A each. It used to be done in kitchens in the US, back when appliances were power hungry. I have done so in my workshop for the same reason. Houses are wired in split phase 240V, with the neutral in the middle. That is, you have two opposite 120V phases, around the same neutral. This is a clever way to double the power, while adding a single wire. In th…

If you're talking about a workshop and anticipating that much ad-hoc power usage, I'd just put two dual 6-20 receptacles side by side rather than splitting one. And then since you're actually creating the premises wiring, stick an (L)14-20R next to them in parallel and get rid of your need to fuss with hacky combiner cords. At least that's what I plan to do when I have the time for such luxuries.

I only very rarely need 240V, if I had permanently mounted 240V machines or frequent needs, I would do exactly what you propose.

Re: "Tinyboxes finally have a buy it now button"

#134

Post by DSMan195276 »

andersa wrote: post #64
michaelt wrote: post #54

Earlier quoted context omitted.

Most likely what they actually mean is: This server has two IEC C20 connectors, rated for ~16 amps, each feeding a PSU rated for 1600W (i.e. 16A @ 100v) If you're plugging in to 110v you shouldn't plug them both into the same outlet, as a 20A circuit can't supply 32A. As each PSU is rated for 1600W you'll have to plug both in to get 3200W even if you're running on 220v - although they'd only draw ~7.2A each in that c…

These are not redundant PSUs, each PSU powers different GPUs in the same machine. Are you sure connecting them to different phases is a good idea? I've been looking for a proper answer to this for a while, because I want to build a similar machine with 8 GPUs (~4500W max load) which would need to be split between two 16A 230V circuits.

Keep in mind GPUs (and the rest of the computer) run on DC, not AC, so there is no phase by the time it comes to your computer. The PSU will step down the AC to the right voltage and then rectify it into DC, and they do that independently so whatever phase they started with shouldn't matter.

Something to keep in mind though is that (at least with consumer-grade PSUs) it is not safe to simply tie the outputs together, even if both PSUs produce 5V, 12V, 3.3V, etc. The voltages will be slightly different and connecting them together will cause current to flow back into one of the PSUs.

You can still use this setup though, the key is that the GPUs do not (or should not) connect the motherboard voltage provided via the card slot to the voltage provided via the power connector. This detail allows you to safely power the motherboard from one PSU and power the GPU from another one, you just have to be careful not to mix connectors on the same card between different PSUs (if it has multiple). Additionally the motherboard should be entirely powered from a single PSU.

Re: "Tinyboxes finally have a buy it now button"

#135

Post by amluto »

bombela wrote: post #132
amluto wrote: post #111

Earlier quoted context omitted.

You can get a two-pole GFCI breaker for this purpose. The prices are a bit silly.

two poles breakers, 2×120V@20A, $USD: - $20 - GFCI, $115 - GFCI + AFCI, $115 Yes it is expensive, but it can also save your life.

Many things can save your life. Most of them don’t have a UL-provided monopoly making it quite unpleasant for anyone to compete to produce the version that fits where you need it.

A 1-pole GFCI breaker, a 2-pole GFCI breaker, and an ordinary GFCI outlet all have the same clever pair of coils, the same IC, and rather similar trip mechanisms. Yet the costs are quite different, and the costs get _really_ absurd if you want a breaker that trips at a level other than ~5mA.

And yes, they’re all very much worth using. I do wish that electrical codes would at least start encouraging the use of GFCIs for 240V outlets, which might encourage manufacturers to start making them, and those would actually be able to compete with each other.

Re: "Tinyboxes finally have a buy it now button"

#136

Post by Hellolearning »

jagrsw wrote: post #122
Hellolearning wrote: post #98

Earlier quoted context omitted.

No it doesn't. A standard EU Socket is not certified for 24/7 3.2kW. You should max. pull 2.7kW. For everything else you need a blue eu socket or camper socket. I learned this due to my EV which is able to be charged through a normal socket but it regulates it down due to this on purpose and has a temperature sensor build in as well.

Is it per spec, or from experience?

from spec. full load only needs to be supported for up to an hour

Re: "Tinyboxes finally have a buy it now button"

#137

Post by Arelius »

bob1029 wrote: post #113
Arelius wrote: post #104

Earlier quoted context omitted.

> All of the Seasonic power supplies that go beyond 1kW or so will trip my shitty (i.e. probably defective) Siemens AFCI breakers. In my experience, the Siemens AFCI just do that. I recommend switching them out for Eaton AFCI. That fixed all my nuisance tripping, especially from induction in other lines

I didn't realize Eaton had AFCI breakers listed for use with Siemens panels (or that they work better). I swapped it out for a non-AFCI Siemens, but if I can make it code compliant I'd much rather that.

Yeah. I think they have seperate models, I forget the details but it's working in my panel!

Re: "Tinyboxes finally have a buy it now button"

#138

Post by Dylan16807 »

zten wrote: post #107
andersa wrote: post #76

Earlier quoted context omitted.

Motherboard and CPU, memory, NVMe drives, PSUs, SlimSAS cables and breakouts, a custom machined case, assembly, support. You're free to try building one yourself for cheaper. If you consider your time for researching/assembling/testing it to be worthless, and are happy with a contraption in a miner frame, then you can probably do it.

PC builds seem to short circuit everyone's pricing logic and drive any labor cost down to $0, just because they're willing to do it for free. Anything above that $0 is considered overpriced.

There are services that will build a PC for $200. It's entirely valid to ask where the money goes, and the answer is not the labor to put the pieces together. There's no reason to assume OP is being dismissive of that specific cost.
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