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Comment by timenova | Hacker News Reader

I think someday it would be amazing to have 1500W to 3000W kettles simply being powered by Type C, and other home appliances too. Wall sockets in most places in the house could simply be the universal Type C port, and since Type C does power negotiation, it'll be safe to connect a low-power appliance to a high-power Type C outlet.

The key requirement for this (after the spec comes along) would be high quality high-power rated Type C cables, and safe high-power Type C outlets. No need for each appliance to have different sorts of cables (mostly irreplaceable and fixed length) which don't fit some outlets correctly.

Maybe after some regulations, it would even be easy to update the firmware of those home appliances to open source alternatives.

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> I think someday it would be amazing to have 1500W to 3000W kettles simply being powered by Type C, and other home appliances too.

I've actually jokingly suggested that USB will go this way. You'll plug in your new induction cooktop with a USB cable you fished out of the junk drawer and all of the LEDs and screens will light up. However, the second you turn a zone on the cable melts and burns your house down because the cable didn't support the USB-HPD-IH 2.3 Gen2x120 spec.

I don't believe the tiny plugs will ever be able to do that. The European power sockets ("schuko", type E/F) usually run with 230V and 13A (even 253V/16A is technically allowed), so up to 3000W and more.

They can get really warm when run at full power. If the sockets are worn out they can even get hot enough to melt the plastic. A few electric car owners experienced that, when they charged their car on a regular socket. (with the higher voltage in Europe it's feasible to charge a car on a standard socket, 0-100% can take as "little" as 20 to 30 hours.)

So I highly doubt those currents could every be delivered on such a tiny and brittle connector. 240W already seems like pushing it to the limits. Higher voltages seem impossible too, there is not enough space for isolation. Small mechanical faults could easily expose those dangerous voltages to the user.

> A few electric car owners experienced that, when they charged their car on a regular socket.

So much so that it's not allowed to provide such an "emergency charger" with a regular Schuko plug when you sell a new EV here in Norway.

I thought I had displaced mine for my new car until I called the seller and he informed me of this recent rule.

Is there no such thing as a fused schuko plug? All of my plugs are G type, and since they all* have fuses, I never put much thought into limiting the amount of current I'm going to pull through a cable.

*: some devices don't have replaceable fuses.

Fuses don't help with overheating cables/sockets that run well within the specs. Schuko is rated for 16A peak, still most chargers only run it with 10A or 13A. I had a nearly melting socket already with 10A.

Most electric car charges nowadays can sense overheating by a decrease in voltage (i've seen a voltage drop from 225V to 205V within a few minutes, and the charger immediately limited the current to 6A). And a lot of them also monitor the temperature of the cables and the plugs.

Now the real issues enters the game: extension cords. If the temperature issues happens on the other side of the extension cord, maybe 20-50m away the charger still measures perfectly fine temperatures on the plug. But the socket the extension cord is plugged in may be already burning.

That's why you should never ever (!) charge an electric car on a Schuko extension cord. Even if everything is in perfectly working condition and rated for 16A.

Why would the cable/socket overheat if it's within spec? I thought that was the whole point of using fuses in the first place.

Roll-out extension leads are extra dangerous though, even if fused. I have a relative that had to jump out of a second floor window on a construction site when someone set all of their batteries charging on a wrapped up extension lead, which rapidly started a fire. I assume it happened faster than the thermal cutoff could trigger.

Why would a car crash if the speed limit is obeyed?

There are many factors that can lead to overheating. Like damaged sockets, Plugs not plugged in fully, dirty plugs/sockets, cheap/old sockets that don't fulfil the specs, wear in sockets that leads to not enough pressure on the pins and smaller contact surface, ...

> I think someday it would be amazing to have 1500W to 3000W kettles simply being powered by Type C

Well this is very unlikely to happen.

To deliver more power, you either need to increase voltage, or increase current.

- The higher the voltage, the easier an electric arc can form between two wires. Cables and connectors are voltage rated depending on the clearance/spacing between their components. USB-C is very compact, it is unlikely it could be used for more than say 20V without starting to create arc issues.

- Increasing current means increasing wire gauge, otherwise the cables will just burn. Ultimately "beefing" USB cables will make them clunky and rigid to the point where it will defeat its purpose. The connectors would need to be bigger as well, to a point where these new high power connectors wouldn't fit regular USB-C connectors.

   > USB-C is very compact, it is unlikely
   > it could be used for more than say 20V without
   > starting to create arc issues.

USB-C has carried more than double 20V since 2021, or 48V: https://www.usb.org/usb-charger-pd

Heh, the German Schuko plug tops out at ~3680W @240V. And that thing is chunky even compared to the US NEMA plug.

To increase the wattage with such tiny wires, you need to increase voltage a lot. Imagine auto-negotiating at 5kV.

That's why power hungry devices are usually connected to a three phase plug. This aside, I think the best would have most outlet keeping the current national standards (let's not forget they deliver AC which is still need by a decreasing number of electric motors) and add a second residential DC circuit using a USB-C outlet

5kV would need the wires really far apart to prevent arcing, no?

The cables would be chunkier but not THAT weird looking. The connectors on the other hand would be wild. You'd have a cluster of deeply shielded contacts, and mechanically actuated shutters might be employed. I have no idea how you would address wet environments other than "GFCI everything"

Interesting idea, I suspect it isn't possible with the existing connector. You either need to increase the voltage or the current.

The new 240W spec is 5A and 50V. Assuming 5A is the thermal limit of the connector and that can't change, to get 1500W you'd need 300V, which is probably higher than the connector can support in terms of conductor spacing.

300V DC is also quite dangerous, 48v/50v is already up there.

Maybe you can get there if the device doesn’t actually require a steady stream of 1500W. For example, induction stovetops often work with cycling their coils. Couple the idea of a charge pump, a whole bank of capacitors and Tesla’s trick of running cables over spec by constantly monitoring temperature and making on-the-fly adjustments, and you might get somewhere.

You may be able to run cables 50-100% over spec for a short time. But not 1000%. Thought experiment (don't try at home!): Take a random USB cable and short circuit a car battery. It will start burning within seconds.

If you short circuit a car battery with a wrench it will melt the wrench.

50 V in the USB-C connector ?

What can go wrong ?

In power-over-ethernet setups, you can have up to 57VDC at the consuming device: https://en.wikipedia.org/wiki/Power_over_Ethernet#Standard_i...

50V is pretty much the limit that is still considered safe for humans to get in direct contact with.

At uni we learned that 30V can penetrate skin in the right (wrong?) conditions. Once it's through the skin, your body conducts really well, so even a tiny amount of current can stop your heart. But you need a path for the current to get across your heart, so I'm guessing that even if 30V gets under your skin, you'd have to be pretty unlucky for it to form a circuit through your heart.

plenty of grounded things you might be gripping with your other hand at the same time :(

And by safe it means 'won't die' not 'pleasant feeling' still be careful with 50v!

With dry hands it shouldn't be bad, with wet or sweaty fingers it probably can become quite a "shocking" experience.

If there is some liquid poured over the connector or if the cable is damaged, this could really become nasty.

As a teenager I touched a phone plug with my tongue. While it only delivered 48V it was far from being pleasant

You're just lucky it didn't ring at the time!

Touching a 9V battery to your tongue isn't pleasant.

Having done both I can assure you that the phone plug experience is far sharper. It's the similar "lemony" shock, but far far stronger

Licking a Nintendo game card is also not pleasant.

Which Nintendo console, what game and for what purpose?

Mmm yes 50 V over pins that are half a millimetre apart. I see no problem with this. No problem at all.

I actually looked into this for making coffee while camping. How hard would it be to boil water with a portable battery pack that contains a few 18650 cells? Regardless of the fact that USB-C at 240W is not really enough, could you do it on batteries?

Not very well. It takes a shitload of energy to boil a cup of water. About 0.5MJ for 8 ounces raised from 20C to 100C. My portable battery pack holds about 100Wh of energy. That's 360,000J. So that battery pack has enough energy to boil one cup of water and not quite a second one. And that assumes 100% efficiency.

I realize that we're talking about two different things: wall outlets vs. batteries, but boiling water is hard.

> I think someday it would be amazing to have 1500W to 3000W kettles simply being powered by Type C

Please, for the love of Zeus, no!

Sure, having a single standard everywhere sounds like fun, but there is such thing as physics...

Also I really don't want people to try to run electric kettles over iPhone USB charging cord.

    > Also I really don't want people to try to run electric
    > kettles over iPhone USB charging cord.

The USB-C PD cables have circuitry in them that negotiates with both endpoints, and declares "yes, I'm okey with transporting 100W".

Whereas I can trivially rewire my kettle in 5 minutes to use headphone wires instead of the properly sized wires it needs, and people routinely do the equivalent of that, e.g. extending their oven, microwave or kettle's cable with the cheapest extension cord they can find.

So it would actually be significantly safer, you can make a USB-PD wire that says it accepts 100W, but actually just melts, but doing so requires significantly more moronic perseverance than doing the equivalent with an under-rated extension cord.

Spec compliant USB-C PD cables have circuitry in them that negotiates with both endpoints, and declares "yes, I'm okay with transporting 100W".

Most people aren't making their own cables and programming what they accept into them. They're just using whatever cables they have that works. If you were a business owner and profit was your short term motive, and you had a factory making different cables supporting different wattages, would it be easier to program the specific firmware that should be on each cable, or just program all cables so they say they "support" the max? Shortcuts like that are not theoretical - ethernet cards are supposed to be programmed with unique MAC addresses, but we've seen out in the wild, MACs be the same on batches of cards, or set to all zeros.

When it's 240W the stakes are lower than when it's 3000W.

I'm not really following this argument.

Because someone released Ethernet cards with duplicate MAC addresses, we should conclude that a future hypothetical USB-PD spec capable of powering a kettle would be more prone to failure than the status quo of bringing your own extension cord?

Electric cords don't need to self-declare their capabilities, USB-PD cables do. So the odds of a mistake on the manufacturer side are lower, as you'd need to pair an incapable wire with the wrong E-Mark chip.

For an extension cord to melt and catch fire all you need to do is for the customer to misread a label, or more likely not read one at all.

If we're talking about the short-term motives of sociopaths, your hypothetical factory will have an even easier time labeling headphone wires as capable of carrying 16A. They don't need to fraudulently manufacture one with the wrong E-Mark chip, just slap a new sticker on the box they're shipped in.

I'm as frustrated with the confusion around USB-C as anyone, but I don't think we need to worry that the problems associated with race-to-the bottom manufacturers in the 15W space are going to extend to 100W, 240W, or hypothetical 3000W cables. The price point, serious failure modes, and potential liability will all serve as moats.

There are numerous examples when the electric cables marked with a proper gauge for the load are actually made with a thinner ones. This is exactly the problem with the extension cords and power strips which literally melt under any serious load (ie kettle and like).

Add to that what now you would need USB-PD chip in any cable, what you cannot use the cable if the chip dies, what they would go directly to the landfill.

Hell, even CAT5 ethernet cables are made of shit for decades, I personally witnessed reruns needed for the lines which were laid with a 'proper' (on the pack) cable, yet didn't work at any meaningful distance.

I automatically assume any and all USB cables, including and especially those with USB-C plugs, are non-compliant wires of Copper where the capital C stands for "Crap" until clearly demonstrated otherwise.

I have been vindicated many times.

The point is that USB-C is used by a LOT of devices that are NOT iPhone and that draw significantly more power, therefore its reasonble to explore standardizing any decive that can fit the specs wattage limitations. The more devices that can be charged from the same cable and plug would solve several problems not the least of which is reducing environment waste.

I have a bag at home scores of AC to DC adapters and cables.

Phui. The Wireless Power Consortium (the Qi people) have the wireless “Ki” standard for your kitchen (Qi - Ki - kitchen, get it?)

https://www.cookwithki.com/

Vaporware boils water best.

That's not enough vapor. https://duckduckgo.com/?q=texas+tesla+tower

I have USB-C for my blender. Well, it’s battery operated, but recharges that way.

https://techcrunch.com/2023/01/07/blend-cap/

I've shocked myself with the end of a USB C cable too many times to believe this (power negotiation) is implemented well.

A compliant USB-C device or power supply is not allowed to expose anything other than 3-5.5V of Vconn on one of the configuration pins.

Only if it senses an upstream-facing port of another device will it expose 5V of Vbus, let alone 20 V (or more recently 48 V) via PD, which would require a complex handshake to prevent exactly that situation (i.e. electric shocks or arcing) from arising.

As others have already said, what you're experiencing is likely an improperly designed power supply (that can happen even with plain old USB-A battery charging and has caused deadly accidents in the past!) or static electricity.

The metal "end" of the cable is connected to ground, not power.

If you're getting shocked by that, you've got bigger problems.

It's the EMI shield coupling inside the power supply, see [0]. Shouldn't happen with properly grounded chargers (but the charger in question is probably two-pronged without a ground pin, like the majority of chargers).

[0] https://electronics.stackexchange.com/questions/476895/ac-to...

That has nothing to do with the voltage/current inside the cable. You can't feel 48V on dry skin.

This is assuming that only 48 V (relative to ground) were present on the cable.

There are many ways in which low quality power supplies can expose up to full main power voltage on the secondary side. For example, with 230 V on Vbus and 225 V on "ground", an USB device might not even be able to tell the difference.

Sorry, I think this must remain a fantasy. Physics is unlikely to comply with your request, no matter how convenient it would be.

The key is to use the USB cable itself as the heating element in the boiler.

Better yet create a 3000W wireless charger, and you can just stick the pot directly on it.

Microwave oven / wireless charger... same thing!

Physics isn't the problem.

USB-C is currently specified for 1.25 amps per pin at 48 volts. If you decide you don't need any data wires and make all 24 pins hot, with the shield as the return path, that's already 1500 watts. And I'm sure you could tweak it to get somewhat more.

Afaik the power cables are substantially thicker than the data ones (and likely better isolated). There's also only 8 unique connections: power, ground and 6 data lines. At best you could get 3x the power with the same pinout.

Those are cables that still support high speed data. If you sacrifice data, you get a lot more pins.

Protocol and pinout incompatibility is a bad idea but it has nothing to do with physics.

In this case, you would presumably make the devices start in the legacy 5V USB pinout, then only switch to sending power over the data pins when the source, cable, and sink all confirm they're specced for it. That should mean there's no protocol incompatibility any more than USB PD is an incompatible protocol.

If you're discounting protocol and pinout why not just change the connector too while you're at it?

Because someone said physics won't comply, and that's silly. We're well within the physical limits of power delivery that won't catch fire.

Also as a sibling comment states, it's arguably not a worse violation of those things than the existing ability to change voltage.

Review the cross sectional area of a USB cable, review NEC ampacity for stranded conductors, and get back to me.

What?

The hypothetical was reusing the plug, not reusing existing cables.

The person you were responding to explicitly mentioned that the cables would need to be upgraded.

For example, a full-size extension cord can be soldered to a USB-C plug without much difficulty.

Whatever wire gauge you want, it can be done. The bottleneck is the pins, and there's 24 of them.

If only LK-99 had panned out...

What's wrong with physics in this scenario? Tune up voltage as necessary, split it via several wires, I think it'll work.

I'd add to that including a more sophisticated power negotiation system. Say I've got an electric griddle and a microwave oven on the same circuit. To maintain the temperature I've set the griddle to requires an average of 750 watts. I'm cooking something on the griddle and I want to microwave something else in the microwave for 1 minute. The microwave draws 1000 watts.

1000 watts + 750 watts = 1750 watts, which is fine for 1 minute on a standard 125 V 15 outlet.

But that griddle averages 750 watts. It is actually cycling between 1500 watts and 0 watts. 1000 watts + 1500 watts = 2500 watts. That's way over the rating for the outlet.

The griddle and the microwave and the house's power controller should be able to coordinate so that when I try to use the microwave it happens when the griddle is in an off part of its cycle.

> I think someday it would be amazing to have 1500W to 3000W kettles simply being powered by Type C, and other home appliances too.

seems like Ki [1] is more the way to go for appliances. just a few hotspots around the kitchen for the kettle or pot.

[1] https://www.wirelesspowerconsortium.com/standards/ki-cordles...

>Wall sockets in most places in the house could simply be the universal Type C port

I absolutely hope such a hellish future does not come to pass.

Why?

Because USB-C ports will physically die long before any electrical wall socket design currently in use ever will. A good wall socket will serve its purpose for centuries over millions if not trillions of insertion cycles performed by the dumbest ape this side of the galaxy.

> high quality high-power rated

You can't get this high power rating on USB-C ever. Because physics. See also: https://www.reddit.com/r/UsbCHardware/comments/wx5ati/commen...

That might happen, but only if we get that LK99 superconductor working.

And then there comes a time where this thing goes Nova. Maybe it even has some smarts and calls the fire brigade via some sort of IOT.

You can’t get 3000W kettles in North America, getting 1500/3000w DC cables would also be absurdly expensive

Note to future self: get some 240V "north american style" sockets installed in my future North American kitchen. And slice off the euro cord on from a euro kettle and wire on a north american style 240v cord+socket.

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