any update on this
I was very excited by this thread until I read through it…
This laptop is too expensive of a gadget to risk potential arcing of a 100 watt+ power supply across USB-C conductors that are unprotected and essentially a direct connection to the motherboard…
There be dragons…
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Same! A magnetic charging card would be great for me for acessibility reasons but it’s just too big of a risk to take for me.
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any update on this??
For those who are interested in full data using a 24 pin magnetic connector, I have some (maybe?) good news; I found an extender that sends the full USB 4 signal across, meaning you can use your eGPU or thunderbolt dock.
https://www.amazon.com/dp/B0D4HFL13L?psc=1&ref=ppx_yo2ov_dt_b_product_details
However, unlike the Hiebee (https://www.amazon.com/dp/B0D4HFL13L?psc=1&ref=ppx_yo2ov_dt_b_product_details), it’s actually 32mm long. In addition to that, I think it’s slighty sider and fatter, meaning that you might need a full cut out of the insert card. I’ve tried a bit at 3D modelling and printing, but it’s not my strong suit. Would anyone be willing to model a holder for it and the magnetic ends?
Uh…what use would that have? I mean, it just hows USB-PD real-time usage, right?
It’s just a substitute cable creations extension - the fact that it monitors is irrelevant, but it supports full USB 4, as opposed to the cable creations or Hiebie one, that only support USB 3.1.
I’m looking to use the connector for full data with an eGPU, so I needed an extender that supports that. Also I suppose you could potentially put it in facing down and then you have a power monitor to see your draw, but being under the computer how much use it would be would be questionable.
I’m still confused what that has to do with a magnetic charging cable. Or why in this case you’d need an extender at all. Just use the USB-C cards to bring the full USB-C port out, and plug into one of the USB4 ones. Sounds like I’m completely missing something though.
Oh, gotcha, the purpose would be to recess the charger and magnetic connector inside the card, so nothing to snag on when taking it in and out of a bag. Similar to the first post in this thread.
Oh, I see. Hm. Why not just get a PCB with appropriate signal traces, except not quite as deep as the current USB-C expansion card, and 3D print up an appropriate case for it. Unless doing full pinout traces is harder than just getting some printed on a PCB, I can see that being possible since it’s got to support such high frequency, and you want to be sure the signaling arrives at the exact same time on each pin from one connector to the next.
I don’t have the know how to do that or where to order it, in one of my earlier posts on this thread I invited others to.
So for 10 bucks and printing a card this is the better option for me. Although I was hoping others might be interested as I could use help getting the stl file perfected.
As discussed previously in this thread, I’d strongly advise against using something like this, the high speed data lines are super sensitive against electromagnetic discharge and having them exposed on a magnetic connector will kill them sooner or later. Especially in climates with a lot of dry air.
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I understand the risk, but am not quite sure it’s as inevitable as everyone is making it out to be. The physical pins, in at least the wide frame of the magnetic adapter, are physically further apart than in the actual cable.
Are you saying that static electricity would be the culprit here? I’ve been using the magnetic connector for 9 months now with no issues, and with this card the pins would be further recessed and protected.
Arcing is a potential issue even with just one pin. The process of connecting / disconnecting even a single pin on its own by definition means there will be a tiny air gap for a short period of time, and the electricity will arc across across that.
You can see in this video 48V arcing across a 0.25 in / 6 mm air gap, and the higher the voltage the bigger the gap across which it will jump. Here’s another video of arcing across a single connection, much higher voltage but I like it as it shows connecting/disconnecting.
Metal is worn away by arcing, and every time the magnetic connection jiggles will cause a bit of arcing and wear. Far more jiggle with a magnetic connection results in far more wear than with a regular connection.
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Connecting is a very minor risk here due to 5V, yes.
But disconnecting happens while it’s already at the full 48V. Here’s a video showing constant arcing in a loose house power connection. The pins aren’t too close to each other, the issue is the tiny air gap in each jiggly connection.
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You need to be careful extrapolating that to an arc in a magnetic connector. The USB connection is limited to 5A and the power supply will have fault cutput protection - but a house connection has the closest thing to a constant voltage source that you will find anywhere, i.e. if you start an arc the current will possibly go to hundreds on amps (which is why such connections should have an appropriate fuse upstream).
Every time the magnetic connection jiggles will cause a bit of arcing and wear. Far more jiggle with a magnetic connection results in far more wear than with a typical mechanically secured connection.
At 240W, that must be 240W÷48V=5A of current going though the cable. Looks like USB-C has four VBUS and four GND pins, so you could argue 5A÷4=1.25A though each pin. And in USB-C, those are some very tiny pins.
I’m not saying it can’t be done, just pointing out why it’s caused so many issues for people so far. It’s not a trivial problem that can be easily resolved in the USB-C form factor. Of course if you change the connector by using fatter pins that are spread out more, and no data pins, then it’s much easier to solve.
i don’t know as much about magsafe 3, apple’s current incarnation, but as i believe i mentioned some time back in one of these threads magsafe 2 had a bad habit of cooking the charging circuit. it was functioning as a consumable component, even though it wasn’t designed that way (and it sometimes didn’t stop with that circuit).
the expansion card CAN potentially act as a sacrificial intermediary, but i know i wouldn’t want to bet on it
A house connection is also ac, so the arc is self extinguishing, dc doesn’t have that luxury.
But the arcing concerns aren’t really about loose connections but regular unexpected disconnects, inductance resists changes in current and will raise the voltage until it’s magnetic field is depleted. Best case it’ll damage the contacts, much worse case it sends spikes of way too high voltage to to data pins which may blow up either the expensive re-drivers on the usb4 ports, the cpu or the internal hub after the esd protection is overwhelmed.
If I really wanted magnetic charging I would make damn sure only the power and cc pins are connected and put the beefiest esd protection I can find on the cc pins.
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I haven’t seen a lot of evidence that this theoretical safety issue is actually a general problem with magnetic charging cables.
There’s no charging cable or brick in existence, for example, that does not have knockoff brands that have fried things and/or started fires.
We’ve all probably heard the stories of cheap Alibaba etc chargers that explode when people use them etc, that doesn’t make OEM chargers inherently unsafe to use because other brands are.
I have had my Volta XL chargers now since the start of 2019 (I had one of their earlier versions before that but can’t find when I started using those) and have never had any funkiness. I use it for my FW16 every day (it’s currently plugged into one).
You see a lot of “Because it works for you it doesn’t mean it’s not an issue” arguments, but I would counter with “Have you or anyone else managed to get a volta charger (or other specific brand) to spark in the mentioned manner?” for example which has destroyed equipment.
If a brand has fried something, you stop buying stuff from that brand and move on to something more trustworthy.
I am at least not finding any signs that people have managed to do so for Volta chargers specifically so I’m not really concerned.