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A Universal Power Bus?
mjpalm21 asks: "A friend of mine recently sent me this story on a new universal power technology that charges devices through your desk. This is a cool idea, but it seems complex. I have long wondered why there isn't a universal power bus (UPB) along the lines of universal serial bus (USB). UPB would work like this: You would buy a n port UPB hub for your desk, and then all of your electronic devices (cell phone, PDA, computer speakers, modem, phone, hubs etc.) would plug into the hub via a standard UPB cable. I would think that the device manufacturers would be all over this as it would reduce their product cost (no need to bundle a power brick), reduce their packaging cost (smaller box), increase customer satisfaction (I know I would be happier), and give them another device to sell (the UPB hub and all those cables)! Why hasn't this happened yet and what would prevent it from happening?"
You can connect your devices using these universal cables.
Different devices require different voltages.. if the device is going to have a power brick built-in to it to convert from "UPB" voltage to what they need, then your UPB is what's known as a "power strip".
-- V
Remember back to the 80s and how clunky things seemed to be? Most of that was due to the battery. Everyone used the same batteries to help bring down costs, but then the final design was around the battery.
Since formed batteries have dropped in price significantly, they can make nice sleek designs and work the battery in rather than the other way around.
Whats this have to do with your question? If everyone could use the same power source, it would mean all devices would be required to support N Volts at N Amps (or set internal resistance accordingly). This means the addition of a step up or down DC-DC transformer to all devices, and taking a step backwards on battery design as you must accommodate the lowest common demoninator again.
However, not all is lost. There is a slim possibility you could add a layer of communications with the block and request a specific voltage from it, thus placing the logistics into the power block.
Figure out how to do that in a small package, and it may simply become the AC outlet. Quite clunky to accomodate at the moment, so specific individual bricks rather than an über brick is far cheaper, smaller, and much less prone to failure.
For now, just be glad the brick isn't an integrated part of the device.
Rod Taylor
The quick response is clearly that you already are supplied with 110VAC, and thus a power strip is your best bet. But that's not what you want, mostly because that's too bulky. Understandible.
The bigger issue is that all these devices have different power requirements. Some want 9VDC, others 12VDC or 5VDC, or even 6VDC. Some want 500mA, others want only 100mA. And all the connectors are different. But you want standards. To do this, you would be required to build a box that could supply any voltage. And at any current. This means the device when connected would have to send a signal back to the power station that says what voltage it's expecting and how much current it wants to draw. Then, the power gets turned up. And if everything goes well there isn't any surges when extra devices are plugged in.
Actually, this question comes up on /. quite often--it's almost routine. The answer is almost always the same, too--just too complicated and ends up being too expensive for the circuitry. People typically like simple devices, with easy to change parts. Wallworts do that. Basic 110 AC is just fine. No need to reinvent the wheel until people are really crying for it.
Long, cute, or funny Sigs are just another form of over compensation, used by geeks, nerdz, etc.
I realize the article says the universal charger is under development. The big problem is failure. When it mis-communicates, you don't drop a packet and retry. Odds are you're device will fry as the power supply may set itself to too much or too little a voltage level causing circuits to fail.
But, I'd like them to proove me wrong.
Rod Taylor
Hmmmm.... lets see here.
115V * 30A = 3450W
Monitor
150W=High 17inch usage
Computer
1100W=enermax 460W power supply
Speakers
100W=decent sized computer speakers
network hub
10W
pocket pc
35W=HP Jornada
cell
35W
laptop
200W
for a grand total of:
1645W
even with a 25% error it still is 2056W. Thats a lot of extra room for mor things on one outlet
Do not go gentle into that good night. Rage, rage against the dying of the light.
I don't think I have two objects in my house that take exactly the same voltage. It would be wasteful if something used more electricity then it needs just to fit some universal adapter.
I've hit Karma 50 and gotten a Score:5, Troll... I win!
However, things still get murky, even in a 5V standard world. You run into issues
- Over current protection of the source
- Transient protection both ways
- Accidental polarity inversion
- Ground loops
- Noise
- Devices supplying power inapropriately
The easy (cheap) way around this is to specify a standard charger that is specifically NOT interconnectable to anything else, thus resulting in the plethora of incompatible devices that frustrate you.My choices for a standard
- 5 Volts, TTL standard power with a new connector
- 13.8 Volt lighter plug, perhaps a mini version
- Standard plug/polarity/voltage sizes for barrel connectors.
- A new 5 volt, 3 phase 10Khz standard power connector
3 Phase power is cool, too bad it doesn't make it into more homes.--Mike--
What he's asking for is a very sensible idea. Airlines have already picked up on the notion that providing a low voltage power source for laptops would be quite handy by removing the need for the power brick, and have helpfully come up with multiple standards . If you think that the idea of a standard low-voltage power source in the modern household--and especially around the computer--is so wayward, just look at the growing number of USB peripherals that are learning to make do with 500mA at 5V in order to live entirely off the USB bus.
In fact I think USB will turn out to be the motivator of a revolution in standardized low power busses, because manufacturers will get used very quickly to the ubiquitous availability of a power source for their TLL logic and stepper motors without having to worry about power supplies. This has never really been the case in the past, serial and parallel devices (almost) always requiring separate power sources.
The standard could be a lot simpler than what some are suggesting. A system could consist of an under-the-table brick that plugs into a wall outlet and contains a switching power supply, with a low-voltage power strip going up to the desktop. The connectors could be simple USB-plug-like affairs with pins for ground plus 12V and 5V, satisfying the vast majority of consumer electronics devices. The standard would specify what the maximum current draw could be at each voltage level, and device manufacturers would simply design their devices towards this standard. Almost everything around your computer except for the CRT and laser printer can run off 12V and a few amps.
Face it, the 110V power system was designed for exactly the same reasons, to provide convenient and standardized power to the devices in your household. Except that that was at a time when your average consumer electronics used tubes, ran its signals at dangerously high voltages, and also doubled as space heaters. In this growingly low-power world, 110V AC just isn't all that convenient anymore. So don't be surprised if the homes of the future will indeed sprout new wall sockets.
These are becoming the standard 12V (13.8V) connector in the amateur radio emergency services. Several companies make power strips that use them. It doesn't help with the multi-voltage end of things... Unless everyone just standardizes on 12V, with regulators/converters in the device to drop it to what it wants...
I suppose Dell who designed my notebook's power supply with a bastardized triangular connector would sign on to this, huh? And Motorola, the company with cell phones that utilize flat connectors compatible with nothing else... and batteries that are engineered to be incompatible between models despite being the same voltage and shape and employing the same connectors and locking mechanisms? (Think StarTac vs. Nextel i1000)
I think the point here is that companies seem to like being the only source for these items. Someone decided a long time ago that being the only source for accessories increases profits and no one has thought about it since.
There are a host of real problems with current power adapters and such. First, wall warts are really pretty bad power supplies. Most are very simple and very inefficient, so even if you had to get intermediate voltages by regulating down DC to DC in some cases, it wouldn't be much worse. They are hot even when nothing is plugged in, that can't be efficient.
My idea is that you could have a well designed switching supply that could take in a range of AC or DC voltages (say 12-270), and put out what you need. The smart portion could be a pretty standard chip that could be used in a wide variety of supply capacities and voltage sets. I'm thinking about alternative power situations too, peddle power, solar cells, fuel cells, wall power around the world.
You just plug it into whatever you got and it senses it and configures itself to whatever is there. Integrating a storage device might be nice too, and the controller would properly take care of battery maintanance as well so you get the longest possible battery life for the technology. It might be complex to design, but it wouldn't need a very powerful processor so the controller chip could be cheap once it is designed.
"Well, that may be, but wait until it's ubiquitous, then they can stop including the conventional power supply."
This is true to some degree, but there are plenty of situations where it would be inconvenient to require a power hub. Sometimes you only have one DC-powered device in an outlet or a given area. In fact, I would say the majoriry of the time this is the case. Certainly, most people could think of a situation where they have more than two wall-warts, but outside of the computer room these cases become more rare. And your whole argument is based on ubiquity, that everything would use this universal standard. I don't think that's necessarily practical. You may be tempted to imagine a range of power hubs, so that you can choose a "lite" version for just these situations. I submit that the wall-wart is exactly this, and that trying to sell as a seperate device that which has always been included (at a higher price, no doubt) is just asking for customer dissatisfaction.
"But surely, as the ueber-nerd that I am, it would eliminate a big mess?"
It would help, no doubt. But really, does it buy you that much? Every device still has a power cord. Yes, you would not have to deal with a number of smaller "power bricks", but you still have to deal with one rather large power brick. Don't expect this device to be small and slim like your network hubs. Instead envision something along the lines of a computer power supply. So you save some weight, and some volume, but in the end all that you're really getting is not worrying about how to make all those wall-warts fit onto power strips. And again, the people to whom this will be most useful (those with a number of devices) will likely already have a large number of power strips, since they're power users anyway. For the more modest installation of one or two devices it's nearly as bulky and doesn't gain you much.
There's also the issue of whether such a device is even practical to build. It would obviously have to support a number of output voltages, which complicates things a great deal. On top of that, since this is a general device, you cannot make assumptions about the relative output strengths required. On a computer power supply, you optimize the design for the 3.3V and 5V outputs since those provide a great deal more current than -12V and -5V supplies, which are mere trickles in comparison. For your "power hub" you can really make no such assumption -- remember that the point is to be able to run anything and everything from this device. And that's the real kicker, it will have to be rather beefy, since it runs everything. Things like modems may not draw much, but things like speakers certainly can. Yes, you could make these things in a range of varying output levels. But again, if you're going to have a "lightweight" version for only a couple of devices, you're better off from a marketing and price standpoint to just continue using wall-warts. So much for ubiquity...
Let's not even get started on the issues of who makes the standards, since after all, every consumer electronics manufacturer has to agree on a standard (and then follow through on it) to make this useful.
So, to summarize:
Nontrivial engineering to provide arbitrary outputs
Only really benefits a minority of "power users" (ugh! bad pun) yet requires universal acceptance
Implies industry-wide cooperation and adherance to a standard (yeah right)
Does not lower product cost (in fact it increases total cost significantly for those who adopt it)
In the best case, reduces clutter marginally
I'm sorry, it's a nice idea but I don't think it's realistic.
well two actully UPB2 and UPB3
the connector shape is open to the manufature, the UPB2 spec is that the power connector have 1 positive and 1 ground, there is a later revision UPB2.1 that has a third lead ground, this was added for safety, if your manufature used the UPB2.1 standard it can support legacy UPB2 outlets with Vise-Grip TM conversion tool.
UPB3 spec is that there is a + - and common sometimes called by it's brand name "3 phase" (this was a name came up by WestingHouse and Tesla)
I would buy it... I wonder if they could connect other stuff (like ethernet) this way... No, not wireless.
Here's a link
and A technology overview
and Another link...
I'm really suprised no one mentioned these yet. They're the funny connectors you plug into your internal hard drives. They provide 5V and 12V DC. This should be more than sufficient for the overwhelming majority of trinkets people need power for on their desk.
All that's needed is a sheath around the four wires, and some cute molding between this sheath and the Molex connector.
Why in the world has no one thought of this before?
If molex connectors aren't your thing, then do something with the mini connectors you use in your floppy drive (although if you're sufficiently clueless it is possible to plug these in reverse polarity.).
The parts for a USB interface (with data) are probably still more expensive than a wall-wart type power supply. I think the cheapest wall-warts are around US$1. USB interfaces are 2 or 3 times as much.
If the USB connector is just used for power, then it's the cost of the connector, which is well under $1.
USB prices will continue to drop, so no other low power bus is likely to be cheaper for the next few years.
If USB becomes more popular, it will probably develope a higher wattage version (or it may have already).
They change the connectors/pinouts on every rev of a phone for a reason, BTW. There's no way they would have gone in for a plan to adopt a standard connector. They may have done something like make a cable that has the UPB end and the proprietary phone end, however. But I doubt it.
-B
Ash and Hickory, straight-grained and true, make excellent bludgeons, dandy for the cudgeling of vegetarians.
I tried something like this, and it failed dismally. Ground loops and interference made the device useless. I eventually gave up and went back to plug packs (or "wall warts" if you prefer).
I don't think so.
Almost no laptops run off of 12V. DC/DC converter (power brick) still needed.
The only reason they supply low-voltage DC rather than AC is because it happens to be
a) Safer
b) More readily available on an airplane. (I think quite a bit of the plane is 48V, but it's easier to step it down to 12 with a switching supply than to make a good AC inverter to give even a modified sine 120VAC, let alone a proper 120VAC sine.)
12V is chosen simply because it means that with a mere physical adapter automotive power supplies for laptops can do dual duty. (And with a physical adapter available at Rat Shack you can power anything powered by the cig lighter plug from airplane power)
retrorocket.o not found, launch anyway?
Maybe it was different before, but since Kyocera inherited Qualcomm's handset division, *every* post-Kyocera phone uses the same data connector. I'm quite happily using my 2035a's data cable with my 6035 Smartphone.
:)
There are only about 2-3 different power supply connectors, all variants of your standard barrel connectors (There's also power available on the data connector). The 2035a and almost all phones of its era have the same power supply, and then the 3035 and 6035 have a different power supply (common to the two of them).
But since the cables are Kyocera proprietary, they can still gouge you on the cables, while saving on manufacturing and design costs.
retrorocket.o not found, launch anyway?
Forget those wallwarts and powerhubs lets just use Power over Ethernet.
Rabi Satter
Every device has different standards on what voltage it wants, what connector it uses, how many amps it needs, etc... Power adaptors for various devices can be:
AC or DC, 1-48 V, 50ma - 5A, any of a slew of connectors and polarities.
The intelligent thing to do would be to pick a relatively common denominator, and make all equipment standardize to it (they're all capable of using voltage regulators, many devices in fact already accept a wider range of voltages than advertised).
The ideal would probably be something like 24 VDC on a medium sized cylindrical connector with negative on the outside, positive in the center. You'd buy a universal power source with several of these dongles hanging off that supplies say 2A max to each connector.
A lot fo the above is arbitrary, but the point is that these things have been obvious for a long time, but device manufacturers just don't care, and there's not real standard out there for them to conform to.
On a related note - I've long wanted to see DC power in houses. Of course the utility should still deliver AC the way it always has - but I'd like to see a stepdown to 48VDC near the breaker panel, and have that 48VDC wired to DC outlets all over the house where many of the AC outlets are. Motorized devices (washer/dryer/fridge/ac) and traditional incandescent lights will still need the AC, but MANY of the other devices you plug into the wall all step down to a low DC voltage inside the unit. Your PC, clocks, kitchen appliances, chargers/power adaptors for all those electronic gadgets, etc.
If you had 48VDC on the wall for these things, you'd be far more efficient with a central stepdown in your garage, you'd be safer, and the devices themselves could be smaller and lighter since they just need a small voltage regulator circuit instead of a transformer/rectifier/etc.
11*43+456^2
Let's face it, I can use a two or three pronged power cord and power nearly every device made by simply plugging it into the wall, in almost any coutry in the world.
Sure there are some countries that use a different system, in which case you need an adapter or equipment that was manufactured for use in that part of the world.
But, in no country that I know of, will you have a problem if your device/power cord works in one location. You will never encounter a problem going to the next building and not being able to use the same cord!
Universal powersupply is already WELL established.