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5v UPS
#11
Well, it was pretty easy to test if I can do charge/discharge at the same time with this particular power pack. I'm sure different power packs have different characteristics. I just plugged the little power pack I had in to see what would happen. Initially, the power pack wasn't charged, and as a result the PI didn't start due to low voltage, or so I thought. I put it on charge for an hour and then plugged in the PI, and it appears that too much current is being drawn, the main voltage goes down to 2.9V and the PI still doesn't start. I tried another power pack with two batteries and the voltage only reached 4.6V. I suspect if a buck converter were introduced this problem could be resolved - clearly this little cheap power packs don't have this sort of thing.

So, I guess the take-away from this is that whatever is applied as a UPS needs to be capable of 2 amps or so at a steady 5V, even if it is for a short period. I still believe this may be the start of something that could work. While I know that others have done this with capacitors, I'm concerned that full shutdown might not be complete before the capacitors were fully discharged. This would be particularly an issue in my case, as I'm using an SSD for storage, which takes a good deal of current.
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Messages In This Thread
5v UPS - by PaddyB - 2017-11-12, 08:46 PM
RE: 5v UPS - by shipahoy - 2017-11-13, 08:55 AM
RE: 5v UPS - by PaddyB - 2017-11-13, 10:44 AM
RE: 5v UPS - by shark24 - 2017-11-13, 02:06 PM
RE: 5v UPS - by abarrow - 2017-11-14, 03:31 PM
RE: 5v UPS - by shipahoy - 2017-11-13, 08:35 PM
RE: 5v UPS - by shark24 - 2017-11-13, 09:16 PM
RE: 5v UPS - by abarrow - 2017-11-13, 10:17 PM
RE: 5v UPS - by shark24 - 2017-11-13, 11:03 PM
RE: 5v UPS - by JD1 - 2017-11-13, 11:16 PM
RE: 5v UPS - by shark24 - 2017-11-13, 11:33 PM
RE: 5v UPS - by abarrow - 2017-11-14, 12:31 AM
RE: 5v UPS - by shark24 - 2017-11-14, 03:40 PM
5v UPS - by tocan - 2017-11-14, 05:37 PM
RE: 5v UPS - by shark24 - 2017-11-15, 09:40 AM
RE: 5v UPS - by tocan - 2017-11-16, 02:19 AM
RE: 5v UPS - by abarrow - 2017-11-18, 03:09 PM
RE: 5v UPS - by shark24 - 2017-11-18, 08:19 PM
RE: 5v UPS - by Sailoog - 2017-11-19, 01:30 PM
RE: 5v UPS - by shipahoy - 2017-11-19, 03:43 PM
RE: 5v UPS - by JD1 - 2017-11-19, 04:36 PM
RE: 5v UPS - by shipahoy - 2017-11-19, 07:52 PM
RE: 5v UPS - by tocan - 2017-11-19, 11:13 PM
RE: 5v UPS - by shipahoy - 2017-11-20, 03:46 PM
RE: 5v UPS - by shark24 - 2017-11-20, 04:23 PM
RE: 5v UPS - by shipahoy - 2017-11-20, 04:39 PM
RE: 5v UPS - by tocan - 2017-11-20, 08:31 PM
RE: 5v UPS - by marko_st - 2018-01-28, 06:27 AM
RE: 5v UPS - by SkipperEarly - 2018-02-02, 05:45 AM
VNC on iPad. - by marko_st - 2018-02-02, 04:58 PM
RE: 5v UPS - by Sailoog - 2018-02-05, 09:21 PM

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