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> 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 negotiate

by avar 3y ago

> 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.

fragmede 3y ago
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.
- avar 3y ago
  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.
  - Dalewyn 3y ago
    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.
  - justsomehnguy 3y ago
    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.

by avar 3y ago

fragmede 3y ago

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.

avar 3y ago
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.
- Dalewyn 3y ago
  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.
- justsomehnguy 3y ago
  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.