Oops, I used up my battery :o

miniyazz · 29 Jun 2013 at 10:18

Plugged my Note 2 into the wall to charge last night, left Wifi tether on (it's only 2-8x faster than home broadband, depending on local traffic) and accidentally left the screen on too (don't ask).

Anyway, woke up this morning and about 5mins in heard my phone turn off and thought 'thats odd', turn it back on and it's on 0% :eek:

I thought my wall charger was sufficiently powerful (normally provides around 1.5A I think) to avoid these situations but apparently not, anyone else epic failed as much?

kona786 · 29 Jun 2013 at 10:20

I always run this app in the background - lets me know exactly how much power my phone is using at 10min intervals - extremely useful

https://play.google.com/store/apps/details?id=ccc71.bmw&hl=en

JediFragger · 29 Jun 2013 at 10:44

Yeah that's pretty weird, no way would my Note2 use that much juice...

kona786 · 29 Jun 2013 at 10:53

Yup very weird for the phone to be using more than 1.5A.

That why i recommend the above app - here's mt S4 when on charge:

miniyazz · 29 Jun 2013 at 11:46

That app looks pretty handy - just downloaded it - does it need calibrating or can I just let it do its thing?
It doesn't seem to provide a charge/drain figure like your screenshots are showing though. Just reads 0. I've set it at 60s intervals for the time being (will reduce this once I've got it set up and working)

miniyazz · 29 Jun 2013 at 20:04

Alright, I've got some mA figures and tbh I think they suffer from not being calibrated to my device. However - drain on the battery while charging with wifi hotspot moving plenty of data, and screen on, is reported at around -50mA, and with the screen off, around 50mA. With Wifi hotspot off for a short time, it peaked at around 350mA charging.
My previous experience e.g. in the car has been that charging from a regular 500mA USB will hold charge steady/slowly charge the phone with the screen off, and merely delay a discharge with the screen on; with a 1A charger I can be running GPS, playing music, etc etc w/ screen on and it will continue to charge. I know Wifi Hotspot is a power sucker but I might try a different charger just in case there's something funny going on.

kona786 · 29 Jun 2013 at 20:06

The calibrating part, you need to input your battery capacity and then put your charger rating in. Let it run for a while then post a screen shot.

I've tried this app on a few phones and it's reporting back accurate figures.

miniyazz · 29 Jun 2013 at 21:04

Alright, will give that a whirl

Cheers

kona786 · 29 Jun 2013 at 21:32

Just in case you don't know,

Battery capacity is normally already correct and there. Should be 3100mah iirc for the note 2.

For the charger the figure is 2000ma.

miniyazz · 29 Jun 2013 at 21:52

Ta. The battery capacity was listed as 1500 in the app, I changed it to 3100. I've always been a little sceptical that the charger actually delivers 2A (found data buried somewhere in the phone that implied it was more like 1493 some time ago IIRC) but you never know, that figure might have been made up by the phone somewhere. The charger makes enough racket anyway!

kona786 · 29 Jun 2013 at 23:27

The charger on the S4 supplies high power from like 10-80% charge, then trails off.

Will be interesting to see your stats, i.e. max power outed.

My sis has a note 2 so I'll install this app when I see her next and see the stats.

I had a whiney charger before. The new S4 one is quiet.

kona786 · 30 Jun 2013 at 13:44

Any luck?

miniyazz · 30 Jun 2013 at 14:59

Alright, here's some screenshots:

Not the most variety of data unfortunately, I'll have to re-run things with Wifi hotspot off at some point. With the screen on and hotspot on, not charging, it looks like it could be draining around 1A. That was on min brightnes IIRC. Looks like the screen uses up 2-300mA depending on brightness, I presume.
Hotspot does destroy battery life..

Also looks like it does slow down towards higher %ages, hard to be sure how much by at present due to my indiscriminate screen usage

snitcher · 30 Jun 2013 at 16:09

does tethering really use that much battery

kona786 · 30 Jun 2013 at 17:25

miniyazz said:
Alright, here's some screenshots:

Not the most variety of data unfortunately, I'll have to re-run things with Wifi hotspot off at some point. With the screen on and hotspot on, not charging, it looks like it could be draining around 1A. That was on min brightnes IIRC. Looks like the screen uses up 2-300mA depending on brightness, I presume.
Hotspot does destroy battery life..

Also looks like it does slow down towards higher %ages, hard to be sure how much by at present due to my indiscriminate screen usage

So thats with constant main charger on and hotspot on with the screen on now and then?

On the last screen shot you lost 7% in about 20mins (charger disconnected) - so big drain from hotspotting and screen on. It seems the charger is still be able to top up charge with screen and HS on.

It would be good to see an hr of hot spotting with screen on and off without the charger.

And also a 10 to 90% charge from the mains without anything rinning to see how much mA the charger supplies.

This is my S4 when charging from 26-100% with nothing really running, but wifi on. And even with the charger off with wifi on (but no apps running, but they are in RAM). Very low usage.

-2mA is extremely low. If stuff is syncing etc I'd expect at a guess its about -20mA to -100. If it's above -100mA I'd say you have a rogue app/service/process.

miniyazz · 30 Jun 2013 at 21:34

I'll work on the hotspotting w/o charging fairly soon, and hopefully a big charge also.

Here's a couple more screenshots. This time showing off charge and off hotspotting but streaming music for a couple of hours with the screen on for 15-25% of the time (in bursts of 15-20s every couple of minutes - sorry, awkward I know!), and then off charge, off hotspotting and not doing anything really with it, where it looks like it's still equalising the power drain (didn't even drop 1% in that 40mins before I got round to plugging it back in; due to the way the program works it can't really give any useful info from that).

miniyazz · 30 Jun 2013 at 22:59

Here we are, some off-charge hotspot data at min screen brightness and then max brightness.

So it can pull up to 1.5A according to that.
My own personal calculations work it out to around 1116mA/hr though, based on 3100mAh battery and 3% drain over 5 mins.

dun · 30 Jun 2013 at 23:27

Just downloaded this earlier today. Any idea why I haven't got the mA column?

kona786 · 1 Jul 2013 at 05:47

miniyazz said:
Here we are, some off-charge hotspot data at min screen brightness and then max brightness.

So it can pull up to 1.5A according to that.
My own personal calculations work it out to around 1116mA/hr though, based on 3100mAh battery and 3% drain over 5 mins.

Yes about 5-6% over 10 mins so about 2.5hrs of hot spotting on a full charge with screen on.

Looking forward to seeing your charger currents.

Dun - what phone do you have - have you set up calibration?

miniyazz · 1 Jul 2013 at 13:29

The other thing (for those screen on battery drainage) is that I have a live background - the windmills one, which aside from displaying windmills also changes depending on the time and on the weather.

Here we have some charging currents. It's worth pointing out that although Wifi Hotspot was off, I have quite a few profiles set via Tasker, some of which only come into play while charging. Also Titanium Backup ran a backup last night.. I'll repeat the test with Tasker off tonight.

Also some from this morning, off charge with screen off. Clearly a very low drain initially, then I use it a bit and it doesn't really have time to properly calculate it again after that. Doesn't look like there's any battery-sapping apps though.

I'll post back with some further charge results with Tasker/TiBackup not running!