What are some of these devices?
Comment on USB-PD is a de-facto low-power DC voltage standard, with USB-C being the universal plug. Hurray!
aard@kyu.de 5 months ago
I’m in my 40s and therefore generally in the “get off my lawn, kids” age.
But I totally agree with that article. I’ve converted quite a few legacy devices with barrel jack to USB-C - and got rid of a huge box of junky old power bricks. Especially for devices I only use occasionally I don’t want to search for the matching power bricks - I just want to plug it into one of the 4 USB-C PD sockets I have installed into my desk.
M500@lemmy.ml 5 months ago
aard@kyu.de 5 months ago
Older notebooks, battery chargers, PMR radios, pretty much everything taking less than 100W DC current.
TexasDrunk@lemmy.world 5 months ago
I converted my small guitar pedalboard to USB-C. I have a multi port charger and a handful of USB-C to barrel plug adapters. Super simple.
My worry was that it wouldn’t be isolated like some of the nicer power delivery systems, but since it was my small one I didn’t really care. They’re actually getting less interference than they were with my cheap pedalboard power supply.
In addition, I have one pedal that gives me more headroom at 18v than it does at the 9v it’s specced for. I haven’t taken out a multimeter but it’s definitely got more headroom now than it did under the old power supply.
M500@lemmy.ml 5 months ago
Oh yeah! I’m dumb! I totally get it. Anytime I buy tech I make sure it’s usb-c if it’s not, then I’m not buying it.
The only non-usbc device left is my wife’s iPhone 13 and a Bluetooth speaker we hardly use.
Have you ever used one of those 9-in-1 usb-c hubs? They blow my mind, how can so much io be handled by that one connection?
frezik@midwest.social 5 months ago
I use one of those hubs and it’s enough to charge my laptop.
Simple answer is that higher voltage is easier to deal with than higher current. USB originally ran it 5V, which would take 12A of current to provide 60W. The wire would be 14AWG, which is 1.63mm thick. Conversely, if you increase the voltage to 20V, you now only need 3A, and the wire can be much thinner/cheaper.
The wire doesn’t care about voltage for the most part. The insulation around it needs to be thick enough to keep it from shorting to other wires and stuff around it, but it doesn’t take much insulation to be rated for 300V.
ShadowRam@kbin.social 5 months ago
Meh. I hate it.
I think society should be moving towards buildings having a dedicated DC source.
International Standardize on a DC wall plug.Each device can step it down easily/efficiently with little electronics to their own needs.
aard@kyu.de 5 months ago
That’s pretty much the “we should all put PoE everywhere” debate, and I don’t think that’ll happen (or is a good idea) - and that’s coming from me as someone with switches providing 1.5kW of PoE power budget in the garage.
The alternative would be a shared conductor like we have now - and while that is working will in data centres doing a conductor in the required dimensions for that would be too big, and potentially dangerous, so that’ll happen even less.
ShadowRam@kbin.social 5 months ago
No, it's got nothing to do with power over ethernet.
It's simply having only one high power rectifier at the breaker box.
And removing all those rectifiers from every device in the house.
We don't need AC in the home anymore. Every device is now using DC, and any other device will still work with DC.
The only thing really left are motors, but even those are going brushless and we can chop half of the inverter out of the equation of those as well.And every device won't even need smart electronics for PD either.
lud@lemm.ee 5 months ago
It would also solve the North America 60Hz and EU 50Hz issue
Since when is it an issue?
A lot of stuff accepts both and the plugs are different anyways so why does it matter?
Btw most of the world uses 50hz not just the EU. Image
m0darn@lemmy.ca 5 months ago
We don’t need AC in the home anymore.
I laughed and wrote out a list of things in my house using AC but I see you’re talking more theoretically. Most of the things using ac in my house are only ever plugged into one circuit, so we could leave those circuits alone. I don’t think USB C PD could handle a hairdryer though, and they aren’t always used on the same circuits (eg sometimes bathroom, sometimes bedroom)
It’s really tough to displace entrenched standards.
deegeese@sopuli.xyz 5 months ago
We did. It’s called USB-C and my house has outlets with AC/USB-C combo.
You want another standard?
AA5B@lemmy.world 5 months ago
More importantly, standards do change. Many of us did the same with USB-A, now a few years later we can update to USB-C by replacing outlets cheaply.
Can you imagine having to replace both the outlets for a new connector and a house-sized converter for new power profiles? So expensive and likely turns a simple DIY project into calling an electrician
frezik@midwest.social 5 months ago
PoE would be that standard, since it’s 48V already and can run all over the house. However, we don’t actually save anything in terms of efficiency by having everything be DC.
frezik@midwest.social 5 months ago
The problem is that nothing wants the same DC voltage. It wants 3.3V, or 5V, or 12V, or 48V, or 18.7V, or whatever. You end up with layers of conversion and save nothing in the end.
Let’s say you start with solar photovoltaic panels, a DC source. It feeds into a DC-DC inverter that puts out a steady 48V. Existing DC-AC microinverters can get 95% efficiency, and DC-DC conversion can be around the same.
In an AC system, we convert to DC at point of use (be it through a wall wort, a floor wort, a USB power port integrated into traditional AC plugs, or something else). This conversion can likewise be around 95% efficient.
In a DC system, we still have to do a DC-DC conversion to get the voltage you actually want at point of use. This is around 95% efficient, as well.
In the end, we stack the same number of conversions at around 95% efficiency no matter if we run AC or DC. Except that assumes we’re coming from a DC source in the first place, like solar photovoltaic. If we come from an AC source, like wind or hydro or pretty much anything besides a solar panel, then we only have transformer losses of converting the higher line AC voltage to what your house uses. Those aren’t 95% efficient; they’re closer to 98% efficient, so we’re better off.
So DC home power sounds like a good idea until you break down how conversion efficiency hits things in practice. If we’re just going to get to the same place, why bother ripping out our current system?
That said, I would like to see PoE get used for residential more. There’s lots of devices that can run off 48V and can also use networking (like smart LED lights). Why not put it over the same plug and skip having to put those devices on a wireless network? Also, you don’t need a licensed electrician to run it. You can’t be an idiot about how to run and terminate it, but you don’t need a license. This would likely be alongside our existing AC wiring, though.
ShadowRam@kbin.social 5 months ago
_ It wants 3.3V, or 5V, or 12V, or 48V, or 18.7V,
Exactly
That's why if you had a 110VDC supply at the wall, you do a simple PWM step-down to the required voltage in every device.
LOADS cheaper/efficient than any USB-C PD circuit...
Saves on transformers, saves on dozens of USB PD wall outlets, saves on communication needed to communicate the PD required between each device and every USB PD wall outlet.
Much cheaper. More efficient.
If only the wall was 100VDC instead of AC
frezik@midwest.social 5 months ago
Why would 100VDC help over AC? You lose very little by rectifying AC.
And again, these aren’t the high draw items in the house. Stuff with motors are, like air con and refrigerators. Those are better left on AC. Why bother when the gains are small?
jadedwench@lemmy.world 5 months ago
In general, you don’t want DC or Ethernet cabling directly next to AC wiring. I forget the exact rules and distances, but you definitely don’t want them in the same conduit at least. Shielding only helps so much. Just a general note as you probably didn’t mean it quite so literally…
I do like PoE though! I have a server rack that powers a bunch of RPi 4s through a PoE+ switch. Had to make sure there was plenty of headroom as RPi 4s can pull just a wee bit of current under full load. I am just happy it works at all.
frezik@midwest.social 5 months ago
It’s running parallel to AC wiring. It’s usually not a big deal in practice, except for higher draw cable.
Bell@lemmy.world 5 months ago
AC steps up or down easily and efficiently, DC not so much.
ShadowRam@kbin.social 5 months ago
No, AC requires large heavy transformers and then rectifying.
DC dropping down to a lower DC is way easier and more efficient.
MonkderZweite@feddit.ch 5 months ago
Wasn’t that a recommendation for LED 10 years ago already?
ShadowRam@kbin.social 5 months ago
Yeah, but frequency drives/inverters were still pretty pricy things back then to for high powered motors for compressors/blowers/etc.
But the cost and efficiency of those things have dropped SIGNIFICANTLY in the past decade..
bassomitron@lemmy.world 5 months ago
How difficult is it to retrofit that into older devices? Because I’d love to get rid of my.“Miscellaneous Power Cords/Adapters” box on my storage shelf.
czardestructo@lemmy.world 5 months ago
If you can solder and heat shrink then search for “usb c trigger board” on ebay and get some for like $5. They will request either 5v, 9v, 12v, 15v or 20v. I’ve found for most older battery powered barrel jack devices a voltage that is an little under spec works just fine. Ive convertered everything in my house and now own a nice USB PD battery bank, life is good.
aard@kyu.de 5 months ago
It mainly depends on the space available in the case of whatever you want to convert. If there’s a lot of space you just get a larger USB-C PD converter board with nice soldering points for the cables. The less space available the smaller the module you need to get, up to worst case trying to do your own.
xor@sh.itjust.works 5 months ago
pretty easy, if soldering is easy:
(first result from amazon, not endorsement: www.amazon.com/…/B08LDJBN8P)