Showing posts with label power. Show all posts
Showing posts with label power. Show all posts

2018-02-11

Mining Rig Power

One amusing thing is that all the GPU risers I see for sale include a SATA-to-6-pin adapter cable.  According to this hugely useful page on "PlayTool", the SATA port can only handle 54W through the 12V pins, whereas the PCIe spec shows the 6-pin connector as required to supply 75W.

In other words, the card could try to draw 75W through a connector only designed for 54W.  Sounds like a fire waiting to happen.  It's unclear how a 120W card would draw power, i.e. if a standard 6-pin is used for the riser and the adapter cable is used for the auxiliary connector, would most of the power come through the riser first?

Well, since I run close to the minimum, 60-75W for 120W cards and 90W for 150W cards, it shouldn't be a problem if 50-50, but if power is pulled through the SATA connector primarily, that wouldn't be good.  I think I'll spend a few extra bucks and get the right kind of cables.

2013-11-11

Solar Power

I've been looking into solar power for prepping purposes, since in the short-term, having comms, non-flammable lights, and such would be useful.  Longevity of such devices in an adverse environment is another matter.

The conclusion I drew after a bunch of reading is that I need a monocrystalline solar cell with one or two AGM 12V batteries and a bunch of AA/AAA Eneloop LSD batteries for buffer.  The monocrystalline solar cells last 10-20 years (some say up to 30) and have the best output.  The absorbed glass mat batteries are deep-cycle, don't leak, and are best to use with solar panels.  (Gel batteries might be better still.)  Lastly, the Eneloop low-self-discharge batteries, 2nd-gen and later, will retain 80% of their charge for 2 years, making frequent refreshes unnecessary.

I'd like to run a smart charger directly from the 12Vs, but that would require an adapter cable with a voltage regulator.  In that case, having an inverter that can provide AC could be useful; the size would depend on the 12Vs.

A gas/propane generator could also be used to recharge the 12Vs, so a charge controller capable of running off of AC would be useful as well.

Another interesting application for prepping would be to buy 12V thermoelectric modules and make a rig to generate electricity from heat sources, i.e. from a cooking stove's waste heat, to recharge 12V batteries.  That's a bit more involved, however.

In my quest for knowledge, I ran into a site where the cyclist describes his setup.  Certainly, Goal Zero makes the best portable solar panel, but it's spendy.  You can get a 100W (monocrystalline) panel for just a hair over twice as much as the 7W GZ panel; however, it won't be very mobile.  The Nomad 7 (v2) is just right for a go bag.

2013-10-07

Dual-Fuel

AD at work mentioned the DuroMax hybrid generator that runs on both gasoline and propane: the XP4400EH.  3500W rated, 4400W starting, with electric start and 240V output for $650.  The downside is that it's made in China, and apparently has some build quality issues.  (Link to softcopy of manual.)  The Honda EU2000i is $1000 and is 1600W rated, 2000W starting, with recoil start and only 120V output.

There's also a site, US Carburation, linked from the DuroMax page which sells propane adapters for other generators.  I'm almost more inclined to spend the money on the Honda and get the adapter, although I need to verify the power requirements for the devices I want to run.