VishmanX
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Smoke from Pi

Sat Dec 28, 2013 1:51 am

So for Christmas I got a powered hub from my parents, its generic but according to Pi Hut it would work. I plugged in my keyboard and mouse and Tenda 150 N adapter to it and plugged it in to the pi starting it up. It worked fine, but every once in a while the keyboard or mouse would stop working. I figured it was underpowered so I put in a stronger adapter on the hub, without checking voltage (still feeling stupid) and it worked for a while, but then I smelled burning. When I looked at the Pi, it was smoking a fine white wispy smoke. I quickly shut everything, down and then rebooted the pi without the hub and the keyboard worked in both USB ports (its model B) but the mouse isn't working. In the mean time, when I shut everything down and examined the board, the bottom of the center of the pi (the parts labeled with C) smelt burned. I just want to make sure if the pi is still safe to use or if I need to use replace it. Thanks.

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default_user8
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Re: Smoke from Pi

Sat Dec 28, 2013 4:06 am

Use it till it stops working(because it will stop working, you let out the magic smoke) and in the mean time go ahead and order a new one.
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drgeoff
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Re: Smoke from Pi

Sat Dec 28, 2013 11:11 am

When a "stronger" PSU means one that can supply more current (within reason) that is OK.

When a "stronger" PSU means one that has a higher output voltage that is not OK.

Also, always check the polarity. Although most now have positive on the centre pin, that isn't universal.

And a few PSUs output AC which doesn't mix well with devices expecting DC.
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redhawk
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Re: Smoke from Pi

Sat Dec 28, 2013 11:17 am

Cut the red wire inside your USB hub that would prevent backfeeding power into the Pi,

Richard S.

drgeoff
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Re: Smoke from Pi

Sat Dec 28, 2013 11:33 am

redhawk wrote:Cut the red wire inside your USB hub that would prevent backfeeding power into the Pi,

Richard S.
While that advice frequently is applicable it isn't always because:

1. Hubs can be constructed with no wires, everything being mounted on the PCB.

2. Even when there is a power wire, there is no law which says it must be red. (Yes it usually is, but if the factory just happens to be out of red wire that day, it may well use any other colour that is to hand.)
Quis custodiet ipsos custodes?

VishmanX
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Re: Smoke from Pi

Sat Dec 28, 2013 1:28 pm

I understand the issues with the Hub, my question is will I be able to save the pi?

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DougieLawson
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Re: Smoke from Pi

Sat Dec 28, 2013 1:43 pm

You must know by now that the answer isn't the one you were hoping for.

Give it a nice burial and a carefully carved headstone.
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RandomPerson
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Re: Smoke from Pi

Sun Dec 29, 2013 6:35 pm

Wow. I will never use the GPIO pins ever. That is plain scary.

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DougieLawson
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Re: Smoke from Pi

Mon Dec 30, 2013 12:49 am

RandomPerson wrote:Wow. I will never use the GPIO pins ever. That is plain scary.
Get an I/O expansion board with an MCP23008, MCP23017 or PCF8574AP between you and the RPi GPIO pins. You can blow one of those chips to smithereens and it costs $1 (or £1) to replace it. They're the sort of chips used on the Quick2Wire, Gertboard, PiFace, etc.

I'm paranoid. Shutdown, pull power, wire GPIO, check, check again, re-boot.
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Criticising any questions is banned on this forum.

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VishmanX
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Joined: Wed Jun 26, 2013 1:50 pm

Re: Smoke from Pi

Mon Dec 30, 2013 2:58 am

I guess i might have got the area it smoked from wrong, its still working all that burnt out was the stuff connected to the hub at the time. I'm actually typing while using the pi right now.

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