Damage on power off?

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1

Hello,

I got a new batch of BBBs from Circuitco.

Amazingly they now come with a warning sticker on the Ethernet connector and a warning in the package to NOT to power off the board by unplugging the power supply because that could cause some damage.

So my question: what kind of damage is meant here? Is it some damage on the used Linux installation or do we really talk about some hardware damage? If hardware: what could be damaged by powering the board off?

Thanks!

2

Shorting out pins on the processor due to improper power sequencing. When you pull the power, the PMIC cannot turn off th rails in the proper order because it runs out of power.

Gerald

3

How should one properly handle the case where the external power can
be interrupted without notice? Eg. the user pulls the plug from the
wall?

Chris

4

So the proper thing is “sudo shutdown now –h” ?

5

Or the push-button... (which does above ^^)

Regards,

6

This is a problem then for random power outages. guess we all need to
use a UPS then to prevent damage ?

7

No, you can add a big cap to the battery pins to let it go down correctly, something that has been discussed here many times before.

Gerald

8

I think the best approach is to use a UPS and detect the AC fault, by any means, and fire a automatic shutdown.
But for an unassisted equipment, how to start it when the power is normalized?

Vinicius

9

Hi,

Is this just a Problem with RevC?
Because it is impossible that any User are using a UPS.

With my element14 are the same problem?

And maybe someone has a link for a solution with the pin Header?

Thank you!

10

What size cap would be recommended? We are using the bbb in a device
that can be powered down externally without any notification. Are the
battery pins exposed on the headers so we can do this on our carrier
board?

Chris

11

I found this:
http://www.element14.com/community/community/designcenter/single-board-computers/next-gen_beaglebone/blog/2013/08/10/bbb--rechargeable-on-board-battery-system

Is this a good way?

12

Hello Gerald,

how “dangerous” is it? I mean, how often this could happen?
Because lost the power supply will sure happen sometimes! So each BBB will be destroyed(?)

It would be great to know which solution is the best.

Thank you!

13

Hard to see. We do not see a lot of failures, .002% RMA returns, but the majority of those failures we see could be alerted to this. It is hard to say as people do not exactly tells us what was going on when they failure occurs.

Gerald

14

How would such a killed board look like - completely dead or just some parts of the CPU no longer working?

15

Flashing power LED or it could just be one or two bad GPIO pins that no longer function.

Gerald