12 volts vs My Computer

Kakawdflied · May 10, 2021

So short story, I was making a small 12v battery pack as a back-up power for my network since power outages is getting frequent. After finishing the battery pack, my multimeter ran out of battery and decided to grab a of usb cable and charge it. I have 2 usb cable, one is connected to a wall charger and the other one is connected to my gaming/work computer. I grabbed the other micro usb cable to test charge the battery pack and then my computer suddenly turned off. To my surprise, the multimeter is being charged with the wall charger and the battery pack is connected through micro usb going to my computer which is supposed to be connected to the wall charger.

I tested my computer components and ram, gpu, ssd were okay but my Ryzen 5 2600 is toasted(not sure but it doesn't work). Im also afraid of testing my motherboard and toast another cpu.

So, I'm not sure on how to go to work tonight(working from home) and I don't have enough funds to replace it.

How could a usb port do such damage to the cpu and does a motherboard has a protection for such scenario like this? Should manufacturers include this kind of features?

Edited May 10, 2021 by Kakawdflied

Trinopoty · May 10, 2021

I wouldn't trust that battery pack simply from the looks of it but that's another point.

It's possible that your battery pack either sent excessive voltage to your PC's USB or it drew too much current from it. Either way, it should only damage the USB chip on the motherboard and not the CPU. Unless the chip was damaged in such a way that the power shorted with the data lines and it sent that voltage to the CPU via the PCIe bus. The chances of this are unlikely but not completely out of the question. Either way, I'd not put power to the motherboard myself if I were you. Send it to a professional and explain the situation so they can safely diagnose the board.

Kakawdflied · May 10, 2021

The batteries were just salvaged from another battery pack and the charge and discharge for the BMS were the same connection, so im certain that the battery pack supplied the voltage to the usb port.

As for the motherboard, I don't trust it anymore. The cost of repair might could be a third of the price of a new motherboard (MSI a320m).

Trinopoty · May 10, 2021

3 hours ago, Kakawdflied said:

The batteries were just salvaged from another battery pack and the charge and discharge for the BMS were the same connection, so im certain that the battery pack supplied the voltage to the usb port.

As for the motherboard, I don't trust it anymore. The cost of repair might could be a third of the price of a new motherboard (MSI a320m).

Since you're new on the forum, here's a little tip. Please make sure to quote the person you're replying to. Otherwise, we don't get notified and might forget to check back on the thread.

LogicalDrm · May 10, 2021

8 hours ago, Kakawdflied said:

How could a usb port do such damage to the cpu and does a motherboard has a protection for such scenario like this? Should manufacturers include this kind of features?

If your USB device would deliver power instead of drawing it. USB is 5V too, not 12V. And no, this is not something manufacturers should be concerned. Its already covered in manuals "Please read before use" part where it says not to connect anything to ports which doesn't belong there. If you connect some personal project or something you otherwise aren't sure is fully compatible, the fault is fully on you.

I would tell to try and go with your home insurance, but they would have all reasons for denying since, again, its not accident, but your own fault.

Kakawdflied · May 10, 2021

2 hours ago, LogicalDrm said:

If your USB device would deliver power instead of drawing it. USB is 5V too, not 12V. And no, this is not something manufacturers should be concerned. Its already covered in manuals "Please read before use" part where it says not to connect anything to ports which doesn't belong there. If you connect some personal project or something you otherwise aren't sure is fully compatible, the fault is fully on you.

I would tell to try and go with your home insurance, but they would have all reasons for denying since, again, its not accident, but your own fault.

Yup, Its my fault and I'm not blaming anyone. My question is, should manufacturers add some kind of protection for this kind of scenario and do you guys want it to? We plug all kinds of gadgets to our computer and sometimes a device that has a battery like our phones, It can get defective at some point.

Kakawdflied · May 10, 2021

2 hours ago, Sakuriru said:

I'm just here for cat :3

Sorry about your processor, maybe go to school for electrical engineering?

That was toothless and heres his brother Mallows.

Anyways, I get dizzy when it comes to math. XD

LogicalDrm · May 10, 2021

1 hour ago, Kakawdflied said:

Yup, Its my fault and I'm not blaming anyone. My question is, should manufacturers add some kind of protection for this kind of scenario and do you guys want it to? We plug all kinds of gadgets to our computer and sometimes a device that has a battery like our phones, It can get defective at some point.

There's cost of effectiveness factor. Phones are not delivering power through USB. Nor is any other device except maybe power bank. Then again, power banks have dedicated port for charging the bank and other ports for discharge. So is this something that happens so often it would be cost effective for manufacturer to implement overvoltage shielding to USB ports? Or is it more cost effective for them to write it off as user mistake under the "Read before using" part of manual.

I don't see any real-world reason for adding such shielding. Not on consumer-grade stuff at least. Maybe for higher-end boards where cost of hardware overall is greater so sinking the additional bucks won't hurt as much.