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Rephrasing my question as requested:

I've managed to blow up 3 or 4 RPis, models ranging from the B (just 2 USB ports) to the B+ to the quad core. It always seems to happen when I plug or unplug the HDMI without removing the Pi 5v power first. The symptoms are always the same, increased current consumption, hotter main processor, no more HMDI output. I can still SSH in but they're running very hot - something is definitely wrong with them.

Has anybody seen any similar behavior, or do you know why this might be happening? Is there anything I can do to further diagnose what's happened to these units?

penitent_tangent
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  • What exactly is your question. This reads like a retrospective rather than a question. I am going to put this on hold until you clarify your question. – Steve Robillard Jul 13 '15 at 02:31
  • Plugging in / out HDMI while it's connected to 5v couldn't be the reason for blowing up Rpi. I do it all the time. – dhruvvyas90 Jul 13 '15 at 03:43
  • I found this strange. It is a sensitive device power wise; very often people come here with odd problems that get solved by swapping the power supply. You should try and isolate what physical components these events have in common -- is it always the same power supply, the same cables, and the same display? If you've done this over and over, there must be some peculiar element involved beyond just hotplugging the HDMI, because I am sure that is a pretty common activity. – goldilocks Jul 13 '15 at 12:06
  • E.g. Notice in the comments on that "odd behaviour" question that it didn't happen with the display on the same powerbar, only when it was on a separate one (but also note both bars were on the same circuit, and in fact led back to the same outlet). I think the pi may be a sort of canary in a coal mine there. – goldilocks Jul 13 '15 at 12:10

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It's difficult to tell for sure but I would suspect some kind of current surge on connection, likely related to one or more faults in power supplies and/or mains wiring.

First off the mains wiring, for your own safety and the safety of your devices you should make sure that the earth (ground for americans) pins in all sockets feeding earthed devices in your setup are actually solidly connected to the buildings earthing system. If it is really impossible to make sure that the earth connections are solidly connected to the buildings earth you should at least make sure the earth connections of all devices in your setup are solidly connected to each other.

Secondly power supplies (whether seperate or built into equipment). You need to connect an AC current meter capable of measuring very small currents between the signal ground on the output of each power supply (or for built in power supplies) and mains earth. I'm not exactly sure what the limits are for commercial devices but on any power supply of reasonable quality the measured current should be well under a milliamp.

Peter Green
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