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Comment by ryao | Hacker News Reader

Has anyone made 12VHPWR cables that replace the 12 little wires with 2 large gauge wires yet? That would prevent the wires from becoming unbalanced, which should preempt the melting connector problem.

As a bonus, if the gauge is large enough, the cable would actually cool the connectors, although that should not be necessary since the failure appears to be caused by overloaded wires dumping heat into the connector as they overheat.

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Might help a little bit, by heatsinking the contacts better, but the problem is the contact resistance, not the wire resistance. The connector itself dangerously heats up.

Or at least I think so? Was that a different 12VHPWR scandal?

Contact resistance is a problem.

Another problem is when the connector is angled, several of the pins may not make contact, shoving all the power through as few as one wire. A common bus would help this but the contact resistance in this case is still bad.

A common bus that is not also overheating would cool the overheating contact(s).

It would help, but my intuition is that the thin steel of the contact would not move the heat fast enough to make a significant difference. Only way to really know is to test it.

I thought that the contact resistance caused the unbalanced wires, which then overheat alongside the connector, giving the connector’s heat nowhere to go.

I think it's both contact and wire resistance.

It is technically possible to solder a new connector on. LTT did that in a video. https://www.youtube.com/watch?v=WzwrLLg1RR4

Uneven abnormal contact resistance is what causes the wires to become unbalanced, and then the remaining ones whose contacts have low resistance have huge currents pushed through them, causing them to overheat due to wire resistance. I am not sure if it is possible to have perfect contact resistance in all systems.

Or 12 strands in a single sheath so it's not overly rigid.

They don't just specify 12 smaller cables for nothing if 2 larger ones will do. There are concerns here with mechanical compatibility (12 wires have smaller allowable bend radius than 2 larger ones with the same ampacity).

One option is to use two very wide, thin insulated copper sheets as cable. Still has a good bend radius in one dimension, but is able to sink a lot of power.

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