Bizarre charging behaviour


levi said:
Make sure you don't have the system on/on charge (it's the same thing when it comes to pandoras without batteries) when you put the battery in
Click to expand...
This would have been helpful to know ~4 hours ago before i started discharging :p
But I didn't have it plugged in anyway so it's all good.
 
stats <30s before it shutdown due to <5% battery:
Code: 
$ cat /sys/class/power_supply/bq27500-0/voltage_now
3604000

$ cat /sys/class/power_supply/bq27500-0/current_now
-635000

That was nearly 5 hours ago now. I'll pop the battery back in and see how it goes soon. Hopefully we'll see some improvement.
 
levi said:
Genius emoji replacement there
Click to expand...

indeed. I didn't spot that. Stupid thing.

I've just put the battery back in and now it's saying that it's at almost 30% charge. Should I let it discharge all the way again and do the 5 hour wait again?

(these stats are from ~15 mins after putting the battery back in)

Code: 
$ cat /sys/class/power_supply/bq27500-0/voltage_now
3687000

$ cat /sys/class/power_supply/bq27500-0/current_now
-201000

200723-172832.png
 
It actually looks good to me, your stats, at the moment. Yeah, you can attempt a deep discharge. I have lowered mine to not complain at the 10% charge, but rather at the 5% (just to not have the nagging red blinking led)
Note that if it is too deeply discharged (not good for the battery), you just plug it in and wait a long time before it even boots.
 
I discharged it back down to 5% again. I don't have the stats unfortunately, it powered down while I was out.
I plugged it back in and it's been charging. it's at 57% with ~4h to go till full.
It powered down on me about 5 mins into charging, but I just powered it back up and it's been charging fine since then. We'll see how it goes.

Any tips on how I might test / fix the wall charger socket? I'd rather be able to charge from either source.
 
One bit of kit anyone with anything electronic should have is a little USB power meter, assuming that's the sort of thing you want to test your power sources. I went for the cheapest of the cheap, but if you're willing to pay a little more you can get ones that show current and voltage at the same time (mine alternates in the display) and you can probably get ones that support logging.
 
that sounds useful. But I meant testing /fixing the cocket on the pandora for the wall charger, since I think that's probably where the issue is
 
the recalibration seems to have helped so far - my pandora seems to be charging normally again. I'll continue to keep an eye on it. Thanks for the tip!
I'd also love to hear any thoughts on getting the wall charger working again though :)
 
Well, you can certainly log it at the end using system info to observe the power going into the battery. Are you still using the original power supply? If so, you can test the voltage at the barrel end as I explained earlier, and unless the barrel connector is wobbly I'd tend to think it remains well connected to the motherboard. If it's something between the barrel jack input and the system info measurement then you're down to looking at power traces and the likes, and if you've still got problems at this point I'd suggest it's time to send it for RMA.
 
Aaaaaand it's back to acting weird. I noticed a while ago that the battery had drained down to 20%, so i unplugged the usb cable and plugged it back in. And I've just noticed it at 103% and still charging.

levi said:
Are you still using the original power supply?
Click to expand...
Yes

levi said:
If so, you can test the voltage at the barrel end as I explained earlier
Click to expand...
antisol said:
I put a multimeter on the wall charger plug. The voltage I get fluctuates occasionally but stays between 5.25-5.26VDC.
Click to expand...
 
I think you need to press a key to start logging, and you can specify to which file it'll write it's stuff iirc. I think there's a page inside system info with most if not all of the keys on it.
 
yeah, on the help screen. You press L to enable logging and arrow keys to set interval. But I don't see anything about filenames
 
aah there it is, in appdata. Logging now.

Does that voltage reading look OK?
 
I was confused at first, I assumed that thing labelled cpu% was actually battery% but on consideration, I think that's unlikely, it probably really is a cpu activity percentage. But that battery clearly goes well beyond what the battery chip thinks is full. It presumably uses some other metric that it's not exposing when it actually decides to stop charging. In these days of lockdown I'd have thought you could put it on charge in the morning and see when the light goes out, because at the very least it does seem to be able to take voltage. It was still taking in 500mA of current when you unplugged it, down from a peak of of about 1725mA.

Edit: It also wasn't showing any signs of heating up. The battery temp recorded only a general decrease in temperature, presumabaly from some original high due to hand heating. If you're paranoid of it catching fire, you can put things in a plastic box with the lid ajar to allow the ingress of the power lead. You'd still lose your pandora if it did explode, but at least it gives you more time before anything else goes up.
 
Last edited:
levi said:
It presumably uses some other metric that it's not exposing when it actually decides to stop charging.
Click to expand...
OK, but isn't that all open? So it should be possible to find out WTF is going on. Do I need to contact ED maybe and find out what the hell is going on? (I have already tried contacting him on the forums, no reply yet, and it seems the contact section in the store is broken, of course).

levi said:
I'd have thought you could put it on charge in the morning and see when the light goes out
Click to expand...
That's not very useful though because it means I have to a) watch it constantly b) remember to unplug it when I'm going to sleep and c) plan and manage and charge in advance when I'm going to take it out with me, as opposed to just picking it up and putting it in my pocket.

levi said:
The battery temp recorded only a general decrease in temperature, presumabaly from some original high due to hand heating
Click to expand...
Nah, wasn't in my hand, that'll be due to the time of day and a drop in ambient temp as evening hit.

levi said:
you can put things in a plastic box with the lid ajar to allow the ingress of the power lead. You'd still lose your pandora if it did explode, but at least it gives you more time before anything else goes up.
Click to expand...
Um, no. I'm afraid that "your house will take longer to burn down while you sleep" isn't really an acceptable workaround for me ;)
 
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