New Efficiency Standards for Wall Warts in the US

The common household wall wart is now under stricter regulation from the US Government. We can all testify to the waste heat produced by many cheap wall warts. Simply pick one at random in your house, and hold it; it will almost certainly be warm. This regulation hopes to save $300 million in wasted electricity, and reap the benefits, ecologically, of burning that much less fuel.

The old standard.

We don’t know what this means practically for the consumer. Will your AliExpress wall warts be turned away at the shore now? Will this increase the cost of the devices? Will it make them less safe? More safe? It’s always hard to see where new regulation will go. Also, could it help us get revenge on that knock-off laptop adapter we bought that go hot it melted a section of carpet?

However, it does look like most warts will go from a mandated 50-ish percent efficiency to 85% and up. This is a pretty big change, and some hold-out manufacturers are going to have to switch gears to newer circuit designs if they want to keep up. We’re also interested to hear the thoughts of those of you outside of the US. Is the US finally catching up, or is this something new?

190 thoughts on “New Efficiency Standards for Wall Warts in the US

  1. This has caused some supply chain issues at my job, sourcing a new converter can be a pain sometimes if the old guy was well tested and characterized in the overall system :(. Looks like most major manufacturers (CUI, TDK Lambda etc) knew about this for a while too, there are alot of EOL wall warts on digikey right now.

    1. Perhaps you can provide some actual information on just *how* these devices need to be more efficient. Is it a question of power factor, quiescent current, conversion under load, or a combination of all of these?

  2. It’s about time. The fact is that this was a case of good enough being the enemy of better combined with out of sight, out of mind (to combine platitudes) and where everyone is supposed to be diligent over wasted energy, these were always a glaring omission.

        1. I used to heat the bedroom in my apartment by just leaving my PC running 24/7. I lived in a duplex with a roommate for a year and we only turned the baseboard heat on once, and that was just because we had company and the living room didn’t benefit from our computers’ heat. Of course, that was back in the heyday of the AMD K6-2 through Athlon XP and 64 before their performance took a dive compared to Intel. Now if I want to use my computer to heat my room, I have to play a few hours of intense Triple-A 3D games (a couple GTX 980s at 60-70C just isn’t as hot as my old GTX 470, which could keep my bedroom 5F hotter than the rest of the house just idling).

          1. If you want to spend money from your electrical bill heating your house using your computer, there are a few interesting points.

            1. the max TDP of a modern PC is far higher than the K6-2 and such computers, especially if you thrown in a couple high-end video cards. They’re just also better at not using power when they’re doing nothing.

            This leads me to point #2…

            2. Make your modern PC do something USEFUL if you want electric heat. Run BOINC with a project like Seti@Home,, Collatz Conjecture, etc, or run Folding@Home, Prime95… etc. Then, when it’s summer and you DON’T want your house to be hot, just stop running the science programs. The energy consumed by generating “information” running a science program on a 300 watt GPU vs running a 300 watt resistive electrical space heater is so near to zero you’ll never see it in a million years on a power bill (actually, it may ACTUALLY be zero, I can’t remember the science.)

    1. Really? About time for a government mandate? As long as I pay for the power why should it be a government problem? I have an arc welder for cripe sake! What about your soldering iron? Do you leave it on? The government should mandate a shut-off switch whenever it isn’t moving. In fact, with IoT it could notify the local power police if you leave it on. Or your radio or TV when no one is in the room, or heating a room you are not in. These crimes can ALL be reported when the IoT gets properly aligned with social justice! Hey, there’s a growth market for electronics and law enforcement equipment.

      Why am I seeing Bruce Willis leaning on a wall with his hands in the yellow circles?

      1. How about you go wank somewhere else? Not because of a government mandate, but because you suddenly realized that shoving your angry junk in other people’s faces is actually a pathetic way to derive a sense of self-worth.

      2. “As long as I pay for the power why should it be a government problem?”

        You would have a valid point if you were paying for a sustainable supply of energy, and you were paying all its associated costs.

        1. I’m in an all hydro and wind region – the place all the Bitminers want to be. But my point is valid no matter where the power comes from. It is offered at a certain price. I buy it. It does not matter what I do with it. Run servers doing environmental simulations, or stupid experiments on perpetual motion with giant Tesla Coils home wound motors. Local Bitminers are having their rates raised to pay for another 200MW build-out, but only because they are a probable short term buyer. We all pay all our associated costs of course. The copper isn’t free.

          1. The correct way would be to price power appropriately. 100% hydro and wind? Great, what you pay is what it costs.

            Non-renewable, however, would instantly be several times the price if you had to pay for lasting pollution effects in some way. Very difficult, as the pollution is spread out over the world. So we don’t. If government started enforcing *that*, it would make power unaffordable, which is obviously undesirable.

            A major side benefit of reducing power consumption is that we don’t need to expand our power generation capability as quickly.

          2. In the UK we pay a “green tax” on energy, which provides money to subsidise stuff like personal solar schemes.
            So, time the U.S. caught up and started taxing the $**t out of you for using energy.

          3. Yeah and you can continue to do whatever the heck you want with it. No one is taking your right to light up your house using glowing nichrome wire. Keep running your powersupplies, or even build your own. You can make some horribly inefficient designs using some basic circuits from the web.

            In the meantime there are those of us who realise that it’s 2016 and the only thing preventing me from reducing my power bill further is the fact that manufacturers don’t put the slightest bit of effort into ensuring power efficiency meaning that I need to unplug devices when not in use.

            Now tell me about how negatively affected you’re going to be as a result of someone selling you something more efficient. I’m here to listen.

          4. Garbz: Why don’t you put in a wall switch that controls the outlets in the room?

            As for effects? I need the heat one way or the other, so Customs destroying shipments of the old style units is incredibly inefficient. The Stupid is strong in this decree.

        2. It makes no difference if it sustainable or not. He pays for it, so sustainability is the suppliers problem. He can do as he likes with that power.
          If he wanted sustainable, he would set up his own solar and wind power and not need to pay anyone for power.

          1. No one is saying all government is bad. What is bad is too much government.

            Energy star labeling for consumers is fine. Making efficiency mandates is silly. I pay for electricity. If I use too much, then that’s the mechanism by which I would be “fined” for doing so.

          2. Efficiency of these things means nothing to me at least 9 months of the year. It all turns into heat and my place heats with electricity! Efficiency police should just bugger off.

            See how quickly this gets complicated? Lets see, given your climate zone and elevation, the weather service modeling for your GPS coordinates, your heating method and amount of tree shading, any special needs regarding heat under the health care room environment act, you can use wall warts that meet or exceed Class C, Type 7.

            People have not noticed much yet, but with productivity increases, the future for young people in the U.S. is government jobs, and that means finding a lot more things to regulate, certify, and police.

          3. “I pay for electricity. If I use too much, then that’s the mechanism by which I would be “fined” for doing so.”

            A lot of cost of electricity generation is not reflected in the price, such as pollution (including CO2) and common resource depletion. A more accurate representation of the cost would require the government to apply hefty taxes to electricity, which would be met with equally strong resistance among consumers.

        1. There are countries that don’t even have a functioning government to exert power over your life. Sadly, they’re all really shitty places to live — totally unrelated, I’m sure.

      3. Really? You are angry, because the government wants to make new equipment more efficient? What the hell is the matter with you? There are literally thousands of other reasons to be angry for something your government is doing wrong and you start whinining about more efficient devices. You are nuts.

        1. The topic isn’t the “literally thousands of other reasons to be angry for something your government is doing wrong”. It is one little increment of eliminating choice and forcing redesign and manufacture of common devices. The key word is “force”. If Zuckerberg and Gates and Al Gore offered to pay for redesigns on a voluntary basis it would be none of my business.

          Some are nuts. Some are sheep. You can choose.

          1. Look, anything near 50% effiency, and especially under, of a wall wart is fucking ridicilous. It’s a waste of energy, a waste of time and a waste of material, it’s a waste of every kind of resource known to man. You lose nothing by this. It’s not that hard to make a more efficient wall wart than 50%. This is unbeliveable, if you want to live in africa, why don’t you move there?

        2. Newsflash J; there’s nothing the Sorry ass government does RIGHT! In the USA, the Federal government is only allowed to deal with external security, regulating Commerce between the states, & national infrastructure! All other controls must be explicitly allowed the Fed by the states! Nowadays the Fed abuses it stated Constitutional limits & Dangerously accrues excessive powers by fiat! That is Constitutionally illegal! We’re either a nation of laws or not! No half-assed “I’ll do what I want! So! The government has NO VALID RIGHT to force any arbitrary law by fiat down my throat! Don’t like it? Immigrate to any freaking Kingdom loving country! This is still my America & screw the Tyrants in office now;nothing but Marxist idiots conning fools to blindly follow their hypocritical false narratives while destroying capitalism & true liberty.. Millions of my fellow American warriors died for! I’m a disabled US Marine who put my brothers in body bags & bled for our freedoms continuance! Hang the traitors high & leave em for the freakin buzzards! Semper Fi, Do or die;&sometimes both!

      4. You have a point there… here in the EU many silly “power saving” standards are being introduced, most of which target (at best) around 3-5% of the average household’s energy consumption. At the same time, the really biiig energy-wasters (Google’s data centers, banks, streaming services) are being protected from such measures. If you very closely, you will find that “new” technologies can be almost as inefficient and dirty as they want (IT products, electric heat pump systems, wind farms in areas with no wind, electric cars etc.), whilst “old” product types get an “eco”-treatment with lots of media fanfare… Again, this is Europe and especially Germany – but the pattern is clearly visible. And yes, we already have a bunch of self-proclaimed “eco-guards”, reporting retailers that don’t display the right “eco-label” in their showrooms. Sadly, it’s “Kauft nicht beim Juden” all over again.

      5. How many hours per day do you use your arc welder? And many soldering irons reduce power when they are in the holder. Primarily not for the electric bill, but to reduce burn of the tips.

      6. You do have a slight point. Except for the fact that you don’t fully pay for the realized cost of creating and delivering that electricity to you. Sure the dollars might be fully paid from you to the electricity guy, but total costs are never factored into the price you pay. No one pays the real cost of bulldozing a mountain to mine coal, or the water polluted from fracking for natural gas, or a dam put up that kills natural wildlife highways.

        The world is innovating. It probably costs less to innovate a smaller, compact, more efficient Wall Wart, which means lower costs in manufacturing and shipping.


    2. It looks like it would do some here a great deal of good to spend some time in places like India where there is little effective top down control of electric power consumers. In many districts the service is compromised by huge numbers of illegal connections to the supply. Every possible safety and technical violation you can think of is commonplace, and as a result both power quality and reliability is a joke. It hacking gone mad. In an attempt to placate voters, laws have been passed mandating that the power company guarantee that they will supply these districts with electricity for fixed intervals during the day, but even that is impossible in most cases.

          1. It is a simple sign of corruption. A crony arrangement between utility providers and government. Government doesn’t want to cut off power from voters or potential revolters and utility allows the situation to develop and is in turn protected from liability by government officials – until something really bad happens and they need a scapegoat. Pretty much SOP in half the world or more.

        1. Mexico is a huge market for Sola constant voltage transformers. The power buildout is so poor that line voltage drops significantly as you get further from the power plant to the point things like refrigerator motors won’t run. Shops that need refrigeration will use the step-up transformers just to get the motors turning. Which increases power used and increases voltage drop etc etc.

  3. Eh more efficient is never a bad thing. At least not until they actually start seeing their bottom line being effected as that $300 million in waste electricity they have been charging people for starts to dry up. At which point they will kindly jack up their rates to compensate :D

        1. Then lobby for increased taxes on coal. That makes far more sense – if that’s the goal – than mandating minimum efficiency standards.

          More efficient wall warts (all else being equal) cost more. So this is a tax, it’s simply an indirect one, and it’s not at all properly targeted at the problem it’s intending to solve.

          In the end, if you really want an increase in efficiency, then you should agitate for a whole-premesis low voltage DC distribution standard. A standard wall plug for, say, 48 VDC, combined with a single AC-DC supply in the fusebox and buck converters at the device would make for a more efficient system overall.

          1. Say you had a choice:

            1. A pro boxer could punch you in the face as hard as they can, then cover all the expenses involved in returning your face to perfect (or even a little better) condition.

            2. They can use less force to punch you in the face, causing less damage. It would cost them less money to fix your face, and you’d heal faster.

            3. Or they could just not punch you in the face to begin with.

            Which of those is easier, cheaper, and less painful? If #3 wasn’t an available option, would you rather have #1 or #2?

            That’s why “just tax it more” isn’t a good choice — it’s easier, cheaper, and less painful to mitigate (or prevent) a problem than it is to fix it.

          2. No, the efficiency regulation is no tax. If they just make a tax, then you have to pay it, as long as the manufacturer will not offer more efficient devices. But you dont get anything for your wasted money.
            With the regulation you pay a little more for the device, but you get more efficient, cooler running, longer lasting devices. I know what I prefer.

    1. Ok, just for accuracy in engineering and science, I have to say it. Improved efficiency can be a very bad thing. The Guillotine, the NAZI “showers” and ovens, slavery, Russian nuclear power plants. Have you ever seen the Soviet production line dental and surgery setups?

      Plus the little light weight 5V 2A wall warts have 170 or 340 VDC which is chopped at a couple hundred kHz or a MHz+. They are very cool but switched mode supplies have always struck me as a lot more dangerous to mess around with, and energy storage in caps is way high compared to linears.

      1. Those of us that cut our teeth in electronic in the days of vacuum tubes had to deal with B+ values over 300VDC routinely. Power supplies used center tapped transformers with 600 volts between the outer legs.

        1. Yes, been knocked on my ass by plate voltages from being too casual with an open panel on older electron microscopes that were all tubes. Portable radios in the 1940’s had 100V dry cell batteries or 3 batteries usually for filament, etc. But those things are not wall warts.

        1. Agreed.These old buggers were retired to a university and the panels opened for probing and adjusting. I think they were Phillips but it was a long time ago. One of them actually blew up on me. A professor called me and said it would not pump down. I sat down, ran the fore pump to the required level, hit the diffusion pumps and and everything was fine. I turned on the filament and BANG the sample holder flew past me head and embedded in the sheet-rock of the wall. There was a crazy strange smell and the lead-glass windows were shattered.

          Turns out the guy (biology department) had “topped up the fore pump with what looked like pump oil”. It was some highly volatile oily looking red stuff he found somewhere. My guess was the vacuum gauge for the forepump was fine but the goo totally screwed up the Mcleod or ion gauges for higher vacuum and the column had a nice explosive mixture. And those old scopes had a big fat column. That become the 2nd of the 3 scopes to become a parts source.

          The x-ray crystallography/diffraction and powder cameras in the geology department were really dark ages stuff.

      2. A well made switching PSU is just as safe as a linear one but they can be more hazardous if they are poorly designed and the HV section is not well isolated from the low voltage section.

  4. Why would Ali express be turned away? I thought it was apple and Microsoft power supplies that were catching fire all the time. :p

    But yeah its good that this stuff is being regulated a lil better. If only on paper. Awareness is important.

  5. Politicians “solving” an engineering problem to generate self-serving environmental rhetoric.

    Efficiency is a function of the conversion performance range over complex loading, and as this varies with bad power factor on US lines it makes true optimization impossible.

    Internationally, the 2/3 of the world that uses dual 220v&110v mode switching power supplies will simply stop shipping 110v parts in the US. This means higher costs for the consumers, and fewer choices for EEs seeking product certification. Recall, the UL class II standards actually made most small transformers very load dependant, and therefore almost useless for equipment… These clowns created the problem in the first place, and are about to make it much worse.

    Conversely… Unlike Politicians, Engineers could likely fix the government’s inability to understand long-term macroeconomic evidence based infrastructure policy through complex systems optimization.

        1. No,

          Local AHJ has full discretion. Usually he defers to the NEC, but that’s not required.

          NFPA 70, like all NFPA standards are funded by selling the paperwork, not by taxes. Taxes, tariffs and new debt fund govt.

          If you fail to pay for NEC committee what happens? If you fail to pay taxes what happens? One you are compelled to pay.

  6. In Australia we have a rating system (stars) for power hungry appliances like dishwashers, washing machines and air conditioners.

    Because we have a 240 Volt domestic (household) system we need to put more effort into keeping poorly made and dangerous products out of our country.

    240 Volts requires more air gaping or isolation on a PCB and quite often some imports are products made for lower voltages with one or two parts upgraded but with the same PCB that has poor air gaping or isolation. These products are extremely dangerous and there have been deaths that have resulted from uncertified and dangerous products being imported.

    We are loosing the battle against these imports.

    It’s not only plug packs / wall warts that waste energy.

    The other day I bought a Wireless (Wi-Fi) 802.11n modem / router. The input is 12 Volts 1 Amp (or 12 Watts). I am guessing that it uses a couple of hundred mW for the RF and half a fly shit more for the half dozen LED’s on it which means it burns off 11 Watts or more as heat. And dam the wifi modem gets hot … not warm … I mean HOT! I live in the tropics and at the heat it was generating I would expect it to last 3 to 6 months max from brand new. I drilled about 200 small holes in it to let the heat convect out.

    1. Extremely interesting. I’d never considered that voltage difference… I have to wonder if maybe the devices you guys have to use down there are hotter than ours because internal voltage regulators have to do more work, and dissipate the extra energy as heat.

      1. Whoa! I hope not. I’m hoping they’re using different taps on transformers or something (auto switching because I see no external switch). I’m in Oz. It’s remotely possible than an uncertified device bought online from overseas might do that, but I doubt it and certainly not for certified devices.

        1. just wide input switch mode supplies the only difference between us uk Europe Au plug packs in most cases these days is the plug.

          Most of the equipment I use for work even comes shipped with a bag of assorted plugs.

    2. Here is an example of things slipping past.

      This is a very common brand product so I expect that it was certified.

      You can see (below) that it was originally made for 110 Volts. The two pads at the top of the PCB are the live input and they’re too close together for 240 Volts so the put an *angle grinder* or something just as rough through the PCB track and connected the live input lower (red wire).

      As I said above – changing just a couple of components doesn’t work because the components become dangerously over stressed in a fault condition.

      In a fault condition the full voltage can be placed across an under rated part and you get this –

      Just to give you an idea of how hot this got – here’s a picture that shows the PCB material on the opposite side is burnt and crystallizing. This is (or should be) FR4 PCB ie FIRE RETARDENT 4

      And this is a night light. The sort of thing you put in a young child’s room. That’s a great place for a fire to start isn’t it.

      1. The blame rides in the china crap sold to all of us as real products. We accept junk like that for one reason… It’s cheaper.

        Would you pay $39.99 for that nightlight that was properly designed and made well? nope, the china $9.99 model is what you grab.

        1. The problem there is that too frequently the 39.99 and the 9.99 options are both poorly made junk. One is just triple the price and people assume that translates into higher quality :/

        2. It’s not all that much cheaper to make, though. Most of the cheap crap is so close to being properly designed and built that the cost difference would be absolutely minuscule. We accept junk like that for one simple reason… we have no way of telling if it’s dangerous or not.

          1. Considering everything made in China is build by low-paid Keebler Elves, it is hard to imagine why they even need to cut corners like they do. You’d expect everything to be overbuilt,and still be cheaper than built by a US or EU worker.

      2. See this is why I’d just use the old fashion 4watt incandescent one.
        It’s cheap and does not catch on fire.
        If you whine over something using 4watts vs 1 watt then you have issues as that’s pretty much nothing in the scheme of things.

    3. Probably they don’t need 12V at 1A. This is just a standard value for cheap wall warts. You also tend to get a better designed one if you buy one that is made to deliver a bit more current, though it may not operate as efficiently as compared to fully loaded.

      1. That’s true, routers usually use 5V, 3.3V and 1.8V rails, most of ones I opened has three switching supplies inside, MC34063 based converter is most common. Newer routers come with 9V adapter, older ones had 12V, and inside they’re the same. Most of the heat comes from main processor, not SMPS or MOSFETs.

    4. Ahh.. does the router have any USB ports to connect things like external USB storage?

      The USB spec, if the router’s been designed appropriately, says that a pre-C USB port should be able to supply 500mA per port. Factor that in + safety margin so you’re not riding on the limit of the power supply spec, and you probably have the reason why it seems surprisingly high for the purpose.

    5. I’ve seen a few of those modems/routers, or even just normal routers, take a higher voltage external feed (say, 12VDC) and convert internally with linear regulators to what they actually need. Sometimes 3.3V, sometimes 5V. Just swapping out that linear regulator with a properly filtered switching one does wonders for heat-related issues.

      1. I have seen them with internal switch mode converters. But very often this are only old fashioned inefficient MC34063 type regulators. Bipolar darlington switching transistor. I don’t know much which is less efficient, except a linear regulator

  7. Yes,

    I mean why wouldn’t you want to replace a 5 component power supply with inherent transient protection with a 14 component power supply that also requires a front end noise filter and voltage ripple in its output?

    Separately, it’s also great that LEDs used in light bulbs may last the 15 to 22 years claimed.. Shame that the capacitors used in the power supplies won’t.

    1. Read the label on the 15 year LED. I don’t have one in front of me but I recall some small print roughly “when used 3 hours per day”. So “10 year” lamps in the hallways of 24 hour facilitates should be expected to start failing at around a year and last 2 if you are lucky. I think tungsten bulbs that are not switched last quite a bit longer. There is a sweet spot there somewhere between maintenance cost and power savings.

        1. How did you get this from my example of a 10 year LED bulb in a 24 hour facility?

          And tungstens nearly always fail from the current surge when the light is turned off. If they are not switched, and not subject to vibration, tungsten bulbs can last 10 times longer than rated, or 15000 to 25000 hours. If their voltage is lowered 10% (or temperature lowered with a dimmer) they go even longer.

          I have NEVER seen unswitched lights, like porch lights or hallways lights in buildings like hotels that burn out every 40 days.

      1. I just replaced a still functioning fluorescent Circlite with an LED bulb. That fluorescent was the last survivor of a lot which was installed in the late 70’s and has been moved a few times, like my own version of that 100+ year old bulb in San Francisco. I also have a 1980’s compact fluorescent bulb with the 4 straight tubes – separable from the base, still works.

        30~40 years ago these things were built to last, with the expectation that the bulb would fail at least once before the electronic part. Of the ones that failed over the years, it was due to failure of both bulb and ballast, and it was cheaper to just replace the whole thing with a curly CF lamp. Just bought a two pack of 60W equivalent warm white LED bulbs at Lowes yesterday for under $4.

        Looks like in another year or so the LED replacements for the straight tube fluorescents will be dropping drastically in price. I’ll do the direct wiring myself on the 12 fixtures in my shop.

        There are LED tubes that work with both magnetic and electronic ballasts. They’re the most expensive. Middle priced are ones that only work with electronic ballasts. Least expensive ones dispense with the ballast and require disconnecting the ballast to directly wire AC line voltage to the tube connectors. Some fixtures require changing the tube connectors for ballast bypass, but those are cheap and there are only a few different designs, which have been unchanged for a very long time.

        Are there LED tubes with LEDs that are aimed up as well as down, to scatter light off the reflectors? I’ve noticed some stores have switched to fixtures with smaller tubes and polished aluminum reflectors. I always figured the old white painted “reflectors” weren’t that great, simply leaving the aluminum unpainted would/should improve light output. You can DIY that by getting a roll of aluminum flue tape and covering the white reflectors with it. Replace the tubes as they die with ones a step down in wattage, the better reflection should compensate.

    1. If the power supplies are above board and getting tested/certified they will be rated for maximum conducted/radiated emissions. If those levels aren’t low enough for you (e.g. your ham gear is getting stomped on by lousy adapters) take it up with the FCC to tighten 15B cert limits.

  8. What’s efficiency? VA? PF? Degrees per Watt? Things change under load, too… things may be efficient under load but not in “standby”…. and vice-versa. I’m all for the intent… but realistically, there’s going to be a plethora of legacy devices out there that will be hanging around for decades… the “impact” will only come from new devices.

  9. Again… ENERGY STAR and FDA.. US is insanely bad at regulating anything and won’t hesitate to try and regulate the free market using the same level of competence(not related I know)..

  10. Sounds good to me. I assume it’s like the 85+ standard where it’s 85% or higher from ~10% to ~90%, so very low/high loadings might differ, but otherwise it gives a good range. And going from 50% to 85% sounds like going from “transformer + diodes + capacitor” to an actual switching circuit. Unless you really need an unregulated supply, I don’t see what the issue is.

    1. There are unregulated switch mode wall warts as a result of cost reduction – they save that “extra” $0.25 for that opto + TL431 and passives. They are called “Electronic Transformers”. They run open loop and relies on the transformer ratios just like the old day. They rely the electronics to have internal regulator(s).

  11. What this means is that ALL power supplies will be forced to use switching technology. This is great for efficiency, but can be a huge source of cost or noise if you are doing anything that is sensitive. A lot of ham radio operators will tell you horror stories of crawling through their homes searching for a wall wart that is throwing a whine right through a frequency that also carries the weak signal from a DX station they need to contact to complete their DXCC award logbook. A lot of hardcore hams set their station up so that it is separate from their house and so that they only have linear power supplies in the shack (or they have linear supplies for everything they can manage… if they need to use a computer, it’s not possible to get away from using a switching PSU, but they will use them for at least the radio equipment).

    Of course, it is possible to build a switching PSU that isn’t “too noisy”, but trying to eliminate all noise begins to put you into a situation where you are starting to just throw money at a wall. When China has to start making choices between safety, efficiency, cost, and noise, it seems to me that the obvious place to cut corners is “noise” first. All they are going to care about is passing FCC testing (assuming that is even going to happen?). They aren’t going to care if the airwaves in your house are too noisy for you to be able to make sense of what you are trying to look at with your Software Defined Radio, listen to with your ham radio, or connect to with your Wi-Fi adapter (though I sorta doubt you have to worry about too much noise in the gigahertz range, hopefully?).

    1. Agreed. Plus the Y1 capacitors in switching supplies can also couple noise into devices. And if two devices are already plugged into different power supplies, then interconnected, the same caps may pass a brief but energetic current spike between the devices. If the connection lacks a ground that’s physically designed to make contact first, and signal pins are sensitive and lack adequate protection, this can actually cause damage.

      I think this new regulation is a good thing, there’s not much excuse for new power supplies not meeting 85% efficiency. But I have been, and will continue, holding on to a stock of old power supplies just in case any device won’t tolerate a newer one. And recommend others do the same.

    2. You do realise how much noise a transformer+rectifier produces, right? They are often far worse than a quality switching supply with PFC.

      It’s much easier to filter conducted noise from the input of a PFC than a simple rectifier circuit, because the latter needs to pull huge discontinuous current spikes at 100-120Hz when the diodes conduct around the voltage peaks.

      1. Yes, transformer/rectifier is very noisy! But it’s low frequency noise that a linear regulator filters out with ease. Many op-amp circuits and power amps can fully compensate for slow supply rail fluctuations as well, as long as they’re not operating too close to the rails. Whereas high frequency switching noise passes through linear regulators almost undiminished. It all depends on what you’re powering and how it was designed. I use switching PS almost exclusively for my own projects, including plenty of filtering when necessary.

    3. Well, to play the devil’s advocate here, I think if your power supply requirements are so exacting, you’re unlikely to be using a cheap wall wart.

      … Says the guy who sells a GPS Disciplined Oscillator on Tindie powered by a wall wart… :D

      1. Haha. Yeah. I own a QS1R software defined radio, which requires a huge 1A (or 2A if you are trying to watch 7 CW/RTTY bands simultaneously) wall wart, in addition to requiring your computer to function. You throw a wall wart that is hopefully quiet enough in with a cheap computer PSU and couple all this together over USB and then pray to the switch-mode gods that you can see anything other than little sweeping lines in the panadapter display.

        I’m sure you’ve sold a handful of your GPS-disciplined oscillators to QS1R customers. I’ve seen links to Tindie for such things in the mailing list for the QS1R.

  12. What I think we are missing is an international standard for a low-voltage low-power circuit (f.ex 12V, 5V, 3.3V, 1 Amper-ish, perhaps to 10 Amper-ish). Not necessarily all of the three, low V switchers are efficient enough.

    We’re nearly there with USB, but a bus topology around the house would be really great. Standardized cabling, fusing, connectors.

    A wall wart would be the exception.

    1. Where I live, I can buy power outlets (the ones that are hardwired into household mains wiring) and they have 5 Volt USB outlets on them. It’s just the ‘wall wart’ inside the wall. I can’t imaging any household wiring for low voltages – too much cost – too much work – too many old houses that can’t have it and Wi-Fi chips are too cheap as an alternative.

      1. I’ve incorporated one or two into my house for charging various devices, they are convenient. There are several different types, some do not put out the required power to charge a device if its on, like, say, certain phones or tablets, or it takes a very long time compared to the wall wart the device came with, so knowing what your requirements are prior to buying one is a must, else one ends up with an expensive wall outlet that is barely useable. I made sure mine had two USB ports, capable of supplying enough power to easily charge some of my demanding devices in a timely manner. Of course, it has a stupid green LED that serves no purpose other than being on constantly. Ive seen actual wall warts and other things, like surge protectors and outlet expansions that have LEDs that serve no actual use other than being on, stealing lower, disturbing sleep cycle.

        1. I found one that has a real 2.1amp outout that will charge apple devices and Samsung devices at full charge rate. Problem is that it costs around $30.00US and most people freak out at that price point.

          Leviton T5630

          1. Yes, dagnabit! WTH justifies nearly $40 for a wall wart for a Galaxy Tab 3? All that does is create a thriving market for crappy ripoff copies on eBay, that cannot output the 2.1 amps the Tab 3 requires in order to charge while it’s in use.

            A 500~650ma charger won’t bring it up from dead, won’t even start to charge it and can barely maintain the charge if it’s already partly charged. A 1 amp charge, which is what most high powered devices pull by shorting the data lines, will still result in a slow drain if the tablet is in use when plugged in.

            There’s some special shenanigans going on inside the Genuine Samsung charger for the S4 and Tab 3 which tells the device the charger’s capability, then the device will pull maximum current. I have a Belkin USB charger rated for 2.1 amps but for the Tab 3 and S4 it’ll only squeeze out an amp. I’d like to build a little adapter to plug in to trick the tablet into identifying the Belkin as a 2.1 amp charger.

            I installed a 3 amp adapter in the dash of my truck, with a pair of USB ports, but with only two wires to each port, all I can get out of them is 500ma each. With the ports buried in molded housings I’d have to make a different connector thing in order to short the data pins to force devices to pull 1 amp. What would be better is having a way for it to check for the various brands of devices and the special tricks they use to identify and provide the full power.

      1. That is not bad. 48V on CAT5 works great for long runs to IP cameras and the like. You can do 12 or 24 but IIRC 48 is the recommended upper end with tolerance something around 60 to 70V DC. For DIY PoE it is cheap but you need to total up current yourself and keep it safe.

        I think the military aviation surplus stuff we got when I was a kid was all 48V 400Hz (They should have used 440 and everyone using it would develop perfect pitch). The 48V used less copper getting power around a plane, especially a big one, and 400Hz meant much smaller lighter transformers. Also better Selsyns/resolvers of instruments and remote controls, though I remember they worked fine on 60Hz. I don’t recall but motors must have just used more windings to make up for less current.

  13. Sounds like a good idea, hopefully it works and there are no loopholes. Personally, I would like to see this extended to all “energy vampires”. Maybe it is in some way, or maybe that problem has already been worked on. all I know is I can’t walk through my house, my shop, or my workplace without seeing stupid LEDs lit up. I remember years ago an experiment someone did with a datalogging power meter that measured how much power was being used in their home, paying close attention to when they were home and gone. They began turning off various devices, and then using a simple power strip to remove power completely. The results were very interesting, especially when one actually thinks about how many devices are never truly ” off”. With careful planning, experimentation, and time, they were able to drop their electric bill considerably with very little impact on their day to day life.

  14. This is complete nonsense. It is about control, not about the environment. This is Big Green Socialist Government Run Amok!

    Linear transformer based supplies left always plugged in do waste a lot of energy over time. But these linear type power supplies are very rare these days, switching power supplies make up the vast majority of supplies shipped today.

    Offline AC/DC switching power supplies which make up almost all power supplies shipped today, ARE inefficient when they are not being used but still left plugged into the mains outlet.

    But WHO CARES? Let’s say they’re 30% efficient when the device they’re plugged into is not being used or off. 30% of almost Zero is STILL almost Zero! Once the device connected to the power supply is turned on, the efficiency jumps to around 90%, which is as good as you’ll get with a linear power supply as well.

    So this type of Government Regulation is pure nonsense. It is a POLITICALLY driven waste of taxpayer money – your money.

      1. Are you planning on paying the electric bill for a billion people? It is all about choice and control. Some parts of the world are used to the control. We never had a King in the U.S. and the struggle between those who want one and those who don’t is ongoing. But the drift towards royal decrees with no recourse or oversight is pretty steady. There is bound to be a lot of argument. From the way the younger “millennials” in my family and their friends accuse me of Boomerizing them, I would guess the royalty/dictator/bureaucracy thing is not far off. So wait a while and everything will be perfect and properly regulated and controlled.

        I wonder what will happen when they notice that Open Source is not controlled by a proper government agency? I’ll bet a dollar that a pull request will take about 2 years.

          1. Are they rising? Not here in the North Pacific here for some reason. Maybe your land is sinking. On the other hand, they have been rising the last 30,000 years as the ice retreats back to the normal state of the Earth as ice-free. I suppose driving a Prius will make it stop – if you take them all, melt them down and build a light shield in space.

    1. Many regulations are just some government weasel coming up with a excuse to justify his or her job.
      Such as going from high sulfur diesel to low sulfur diesel did cut a lot of potential acid rain but going from 500ppm to 50ppm did little.
      But going from 50ppm to less then 15ppm was grasping at a straws and introduced supply problems with infrastructure negatively impacted the reliability of diesel engines.

      1. Some EPA yokel tried demanding that dioxins and other things in the Columbia River be measured in parts per quadrillion. Nevermind that every time there’s a forest fire in the Snake and Columbia watersheds, followed by rainfall or snowmelt, the natural dioxin levels in the rivers go up a bit.

        Can’t “clean” the rivers to the equivalent of distilled water.

    2. There are big differences: I have one crappy 12V/1,5A switch mode PSU from an external HD, which burns 3W in no load. It gets very hot already in no load. I have another one which takes between 0,1 and 0,25W – I can not measure it more exact.
      I would prefer, that the crappy type will not be produced and offered any more, because when you buy a product like a HD you do not know which one is in the package.

  15. I say it’s about time. Some of those wall warts aren’t much better than the “hoverboards” that were catching on fire this past year.
    Since everyone is throwing in their two cents about govt’ regulation though. I am opposed to extraneous regulation and they regulate so many things that I think they shouldn’t but in this case, I see no problem with a minimum efficiency rating.

    Antoher thing I’d like to see go away, though I don’t know that it deserves regulation, LED status lights on wall warts. I just had to buy two replacements, and it mentions it no where on the packaging, and there were two tiny little holes on the front of the case that are barely visible. Until you plug it in. And get a high output blue blast of light into the face. Doesn’t mater if anything is turned on. It’s on as long as it’s plugged in. So… I guess that’s to make me want to conserve power by unplugging everything right? Unnggggghhhhhhhhhhh.

  16. I pay for what crosses my meter!! That makes what I do with it my concern and NO ONE ELSE has any right to say anything about my electric use, period! The Architectural lighting of a few bridges around my county with HALIDE lights burning 12 hours a day every day burn a thousand times even ten thousand times the power each DAY more than ALL the wall warts I own, have owned, or will ever own could use in a decade!!

      1. You have a right to say whatever you want – guaranteed in some places.

        By the way, your breathing is depleting the oxygen levels at my place. (And I was determined to not do any secondary comments when I opened this page :-)

    1. Or how about the power used by the underwater electric fence that maybe keeps the asian carp out of the great lakes? The asian carp that the govt introduced here. Takes alot of wall warts to make up for that stupidity.

      And what about all the ones I have already? I’m supposed to replace all those at my expense I would assume….

      1. How many times have you needed to replace something that gets new restrictions? Did you need to replace all electronics, when lead was forbidden to be used in electronics? Do you think anyone or anything has the resources to uphold a regulation where consumers need to replace all the wall warts they have? I think you are safe.

    1. Because the walls would be filled with wire the size of welding cable. More copper, more expensive.
      Also, in the past, AC current was easy to convert to other voltages, and then rectify and filter at the point of use.
      Since low cost switch-mode converters have come on the scene, the need for AC has become less important.
      So, for most applications, you could wire your home for 48V DC and convert as needed without the need for huge gauge wire in the walls.
      Most large appliances are already available (or can be converted) to DC. Power hungry devices (like air-conditioners) are a problem due to the large power draw, but nothing some re-engineering of the compressor can’t fix. Small air conditioners are already available for DC.

      1. Around here, most real power hogs (electric stove/water-heater/”furnace”) already run on 240V instead of 120V*, not sure about air conditioners. So if you replaced all the ordinary 120VAC circuits with 48VDC runs, and kept the 240V runs separate (possibly convert to 240VDC), it should work out.

        *For the rest of the world: North American homes generally are fed two 120V lines, 180deg. out of phase, so you get 120V from either line to neutral, and 240V from one line to the other. All general-purpose wall outlets are 120V, with 240V runs only at specific major appliances.

        But I’m not sure what good it’s supposed to do in practice. Sure, it technically means 90% of your wiring is “extra low voltage” and doesn’t come under the same safety rules as line voltage (“low voltage”), but you still need double the copper to accomplish that, and it’s not really any easier/simpler/cheaper to make a DC/DC SMPS than an AC/DC SMPS. And as soon as “safe” 48VDC becomes popular, you can bet morons will find ways to electrocute themselves and burn their houses down with it, so the rules will be “fixed” so that “extra low voltage” means, let’s say, 30V and below, instead of 60V and below, and you’ll be back where you started, only with twice as much copper in your walls.

        Honestly, while a changeover is completely impractical for many reasons, if one were to happen, I’d rather see us move to 240V — existing homes can keep the wiring in the walls, just redo the outlets and service panel, and you get double the available power! (Use some sort of Europlug-compatible socket, please.) Or, since we’re dreaming anyway, screw the existing wiring. I *really* like the Swiss 250V/400V 3-phase system, and their family of downward-compatible plugs and sockets — look it up.

        1. It’s 230V/400V :-) and its not only Swiss, its in whole Europe. What is very good. So compared to this you have already nearly ELV and double the copper in the walls. One time in the USA I have seen a room/window airconditioner which ran on 110V or 120V: the cable was very thick and very warm.

      2. GE had a whole line of 36 or 48V appliances in the late 1930’s and 40’s. It was for farms and other remote areas with windmills like the Jacobsen or Airmotor (IIRC) which would have a little battery shack. The Rural Electrification Act killed the wind power and off-grid industry in its infancy.

    2. DC doesn’t travel well over distances. Even over a few feet you’ll start to notice voltage drop, let alone wiring around the house. The wire converts the extra energy into heat because of its own resistance. This is why AC is used.

      Some industrial rooms have local 48VDC supplies because you can directly run buck converters from that, for specialized equipment where having 100 wall warts is impractical and you can easily filter/control the power supply as isolated from the power company.

      1. For a given potential DC travels quite well over distances, better than AC in many instances, voltage drop is a function of conductor resistance. It’s the low voltage aspect that makes voltage drop an issue, which is why we use 100/200V services in the home.

        1. I agree. The current is the issue. To power a 1200W load with 12V you need 100 Amperes of current. If your wiring resistance is 0.1 ohm, a 100 A current flow gives you a voltage drop of 10 Volts.
          Ohmic losses in AC systems are no different at the frequencies used for power distribution.

          1. Whole premises LVDC would likely be 48 VDC rather than 12 for the reasons you cite. 48 VDC is the usual choice because 50 volts is considered the threshold for “high” voltage.

    3. LVDC would likely be 48 VDC instead of 12 volts. 48 volt wire wouldn’t need to be so large, and a buck converter to bring that down to the operating voltage of the device could be made more efficient than a flyback converter to make the same voltage out of 120-240 VAC.

      It would not be necessary to replace the power being supplied to the premises, just add a premises LVDC converter and a DC circuit breaker panel. The whole-premesis AC-DC converter could be made much more efficient than the collection of wall warts it would replace.

    4. There is a very interesting development going on.

      To avoid paying licensed electricians in certain parts of the US, PoE is being expanded to handle much higher wattages than the 12/24 Watts it was originally intended for. Now its expected to go right up to the 150Watt limit for power limited wiring. Because this is low voltage anyone can install it, no licensed electricans needed. This means that in a commercial building the same low hourly wage guy who pulls network cable can also do all of the lighting work. This is a brand new development. FYI, this is all DC.

      Separately, BLDC motors are taking over just about every appliance. These motors are more efficient, hence what used to take a 60Watt cap-start AC motor can now be done with a 35Watt BLDC motor. The drive chips for these motors are relatively new, but once all appliance switch over to BLDC’s there will be very few things within a house that couldn’t be done with DC.

      Next, for the houses that have alternate means of power generation, that generate DC, there would not need to be a large single-point-of-failure inverter to convert your DC alternate power sources into the synchronized power mains. DC is a hell of a lot easier to “match.”

      Looking at these developments together it seems likely that we’ll be seeing a switch over from AC to DC when it makes sense for the infrastructure.

      The one thing with DC is safety though… If the circuits are not power limited, and a fault occurs, DC likes to weld.

      The next 20 years ought to be interesting.

  17. There is a IEEE standard for 72v dc, connector and all. It’s mostly for sever rooms.
    It’s amazing that 12v dc is a standard in the mobile world yet there is no workable global standard for it’s connection. Coaxial plugs (too many sizes) and cigar lighter (pops out) are good examples.

    1. For 12V, I think they had the right idea in the early days of electric lighting, when electric plugs weren’t invented yet. The first electric appliances “plugged” (rather screwed) into light-bulb sockets. Combine that with one of the standardized bayonet-lock sockets (I’m thinking BA15d, but could be talked into larger or smaller), rather than the Edison-type screw sockets, and you’ve got a beautiful standard.

      Of course, applies, as always.

    2. Dymo using an extremely common connector for 12v power supplies on the 24v supply for their Turbo 400 label printer. Quite easy to accidentally jack that into an external hard drive and short the 12v TVS diode. Fortunately, removing the TVS diode from the drive, and making damn sure to never plug the wrong supply in again, fixes it.

      Someone at Dymo screwed up, never should have used *that* size of power supply connector. The IEC established various power cord connector types for AC line voltage, WTH didn’t they for low voltage DC so that there’s one for 12v and an physically incompatible one for 24v etc? It’s lawless anarchy, electronics manufacturers use whatever the heck they want and woe betide you if you get devices that happen to use the same connector but the supplies are different voltages.

    1. Numerous studies done worldwide since the 1970s have tended to conclude that daytime running lights improve safety. This being the case energy is being used to do something useful, while by definition making wall warts more efficient would be saving energy that is not. Hardly comparable.

        1. I’ll help you out.

          Here’s one :

          For the most part, none of the results are statistically significant. The one that is fails to exclude the impact of dawn and dusk, and when it does, once again becomes insignificant.

          Most of the research that has been done was done in Northern Europe, where daylight conditions and durations are starkly different than in the continental United States.

  18. In Ontario Canada It’s not the consumer thats the problem. Its the government with OVER PAYING the so called people that are running our electrical companies. I wish I could get a severances of 100’s of thousands of dollars for getting fired.

    This is another only in Canada PROBLEM……

    And then there is Quebec. Electric Heat is a norm…. Come on.
    They should ban electric heaters in north america as well.

    And I am all for saving the environment (I have solor panels on my roof)…. BUT PLEASE have the right people that know what the hell they are doing do the job.
    And not some politician that cant even screw in a light bulb..

    1. I have installed a lot of so called energy saving systems. The cost of installing and the foot print of making the systems far out ways the saving of electricity. I wish that some one would do a study on that.
      Not saying that they are all bad but the majority of them really do not do what they are meant to do..
      How can you justify spending $30000 extra to save $2000 a year and then replace it in 5 to 10 years. How is that saving the environment.

      1. In my state, a few years back there were some politicians bragging about the annual energy savings of a new solar farm on a military base. I looked up what the final price tag to build solar farm was and calculated a payback period of at least a century. They must be some magical solar panels made with unicorn dust to be able to last a century.

  19. The Government can’t even govern itself. You may accidentally write a bad check, it’s an anomaly, and you pay thru the nose to correct it. The Government “operates” by writing bad checks on a daily basis. It’s equivalent to you being able to print a limitless supply of your own money and still spending more than you can print. Don’t complain about all the cheap Chinese crap, The Government has already sold its soul, lock stock and barrel, to the Chinese, starting with the panama canal. Complain to loudly and the Chinese may decide to come collect the incredible debt we owe them for financially supporting our “way of life” for a quarter of a century. Don’t try removing the splinter from my eye while you have a board in your own.

    1. Essentially the government(s) are stealing “money” out of people’s pocket (by reducing in buying power) by maintaining a mild inflation. Sucks to be the working stiff.

      China have been selling off US dollars to maintain their exchange rate for the last while as their economy slow down.
      They had 1.3 Trillion, so that’s a tiny drop in their reserve. Not a big issue unless they dump a much larger amount than what the market would soak up.

      That’s what I think.

      1. Some parts of the Chinese “banking” system have been selling. But communist party leaders and their relatives have been moving assets out of China as quickly as they can without causing to rapid a collapse. They have a name for it – capital flight. The richer business owners saw what was happening and joined in. But Party members had a running start and now with their assets safely offshore they want to restrict or stop capital flight. It is a house of cards. Another Renminbi (CNY) de-value coming up pretty soon.

  20. Am I wrong in thinking that this will have very little impact? Sure, wall warts from 15+ years ago were of the linear type and less efficient, but I find it to be very rare to find them now (I was going to say that I haven’t seen one for sale (new) in years, but I actually do have one little 200 mA charger that is too hefty for a switched-mode transformer, so I’ve seen one in the past few years). There may be some in use if you don’t clear out old electronics like most present here, but even the cheap crap (dangerous) phone chargers are switching. Who actually sells linear chargers anymore?

  21. Efficiency can only truly come from innovation. The government can try by regulations, but what’s the point if they don’t even understand what it takes to get to what they’re asking for? They’ll need to consult with the people doing the innovating anyway.

  22. This just means the companies that make phone chargers and the like will have to put a bit more effort, and maybe a couple of pence worth of extra components, into making their stuff more efficient. It won’t affect ordinary people at all. It’s very unlikely to make a price difference. Might even stimulate the components market a bit.

    Pretty sure this new standard only applies to manufacturers. You’ll still be able to use your old PSUs, just means next time you get a new phone or whatever, the PSU will be more efficient. If you need an old-fashioned linear PSU for your radio rig, build one, they’re not complicated.

    But cumulatively, that tiny difference adds up, and maybe it’ll save building a power station. Certainly will save a few tons of CO2 and the like, and speaking as someone who finds the weather bad enough as it is, that’s a good thing.

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