DR800 V2 Beta Firmware Battery Test

[catharsis]

With zooming & panning and just reading PDF: 99% to 93% in 24 hours of sleep. I'll leave it in sleep mode at least one day more.

[CoolDragon]

Originally Posted by catharsis

With zooming & panning and just reading PDF: 99% to 93% in 24 hours of sleep. I'll leave it in sleep mode at least one day more.

6% down in 24 hours of standby/sleep is in line with a lot of reports here (both v1 and v2beta firmware). Assuming you normally don't change zoom factor on ereader very often, one big battery drain factor seems to be related to panning. It would be interesting to see how much battery drain (in terms of percentage) it will cost per, let's say, 100 panning operation with stylus.

[AlpGlide]

Originally Posted by CoolDragon

6% down in 24 hours of standby/sleep is in line with a lot of reports here (both v1 and v2beta firmware). Assuming you normally don't change zoom factor on ereader very often, one big battery drain factor seems to be related to panning. It would be interesting to see how much battery drain (in terms of percentage) it will cost per, let's say, 100 panning operation with stylus.

I just disable zoom and panning. They are not so helpful.
another thing I found in Beta V2 is that when I start reading a book from "Continue Reading", turning page is a pain, need to wait tooooo long. but if I start from SD card, it is as good as before (V1).
Is this a bug?

[Shaggy]

Originally Posted by CoolDragon

6% down in 24 hours of standby/sleep is in line with a lot of reports here (both v1 and v2beta firmware).

Assuming it's roughly linear, that's a little over 2 weeks of battery life in standby (aka 400 hours), which is normal.

[catharsis]

After a reset before sleep: 92% to 84% in 24 hours of sleep. Not that happy about it...

[Shaggy]

Originally Posted by catharsis

After a reset before sleep: 92% to 84% in 24 hours of sleep. Not that happy about it...

What were you getting with the v1 firmware?

Also, if you don't mind me asking, what are your expectations?

The numbers you're getting seem roughly in line with around a 2 week standby battery life (6% would be 16 days until 0 power, 8% is 12 days). That seems to match up with what others have seen, and is fairly typical for similar devices. Do you mean you're not happy because it was significantly better with v1, or you're not happy because you were expecting it to run for longer than 2 weeks on a single charge? I saw a little over 2 weeks with mine originally (with v1). That also included a couple hours reading per day, but I wasn't doing any zooming/panning/etc with v1 obviously.

Because there is not a real "off" mode for the DR800, it's always going to be using some power when not in use. It would be nice if they could add an option in the future for the user to truly power it off, but the trade-off to that is a longer start up time when you want to use it again.

Personally, I'd like a short press of the switch to put it into sleep mode and a long press of the switch to shut it down (rather than just reboot). I've seen some indication from other users that adding a script to the menu that would shut it down might be possible. Haven't seen anybody really looking into it lately though. I may try and play around with that some if I can find the time.

[MobileTechReview]

Yes! I've noticed the same thing-- page turns take a very long time, but I hadn't associated it with the continue reading function until you mentioned it (since I almost always go back to my book that way).

Originally Posted by AlpGlide

...
another thing I found in Beta V2 is that when I start reading a book from "Continue Reading", turning page is a pain, need to wait tooooo long. but if I start from SD card, it is as good as before (V1).
Is this a bug?

[catharsis]

@Shaggy: first of all, my overal impression of the DR800SG is that is a great device, at least after v2 firmware release. I used v1 just for few hours so I can't say that much about it.

About why I was unhappy about battery: 6% seemed ok in the first day, 8% a bit much. I suppose Li-Ion batteries don't discharge linearly, so I'll be monitoring the device few more days, just because I'm curious. Anyway, the battery life is enough for me, but at the beginning it was confusing with reset and no power off (I'm the kind of guy which first uses the device and then reads the manual).

Edit: in about 23 hours of sleep it went from 84% to 78%, so probably the 6% per day is the normal rate.

[Shaggy]

Originally Posted by catharsis

About why I was unhappy about battery: 6% seemed ok in the first day, 8% a bit much. I suppose Li-Ion batteries don't discharge linearly, so I'll be monitoring the device few more days, just because I'm curious.

It could be the battery discharge is slightly variable, it could also be that the percentage the battery meter is reporting back to the device isn't really that precise. When the meter says 92%, does it really have the ability to measure it down to 1% at a time, or is it doing some extrapolating? For now, I'd probably average your two numbers out and say it was 14% over 2 days, so roughly 7% per day. I think looking at it in longer intervals than 24 hours would help get rid of any minor inconsistencies as well.

What I did when I first got my DR800 was to charge it up to 100% and then make note of the date. Then I just used it normally without doing any more recharges until the battery completely died and it shut itself down. I forget the exact number (it's in a post on here somewhere) but it was around 2 weeks. Then I averaged that out and estimated that it will discharge approximately 7% per day.

That's going to be effected by usage patterns though. I typically only used it for reading a couple hours a day, so a heavier user would see more discharge. Also, using features like the stylus and 3G will drain the battery faster, etc. Everybody's usage pattern will probably be a little different.

It sounds to me like you're in the ballpark for what the device is expected to do though.

[catharsis]

78 to 71 in another 24 hours, so it's about 6-7% per day, in average. During this time, I used the reader for 5 mins per day and then left it in sleep mode. I think I will continue that a day or two since I don't have any time for reading. It's Vappu here (1st of May), good time for getting drunk

Later: 71% to 57% in about 48 hours of sleep (the average tends to 6-7% per day)

[ErikG]

Egnos and HansTWN reported the failure of dr800 to go to sleep automatically along with high battery drain.

I have observed the same issues on my DR800S.
I had for several months no issues with v1. Since I installed v2beta I experience sometimes that the device doesn't automatically go to sleep. In one instance the settings screen was on and I found it a couple of hours later totally irresponsive and zero battery power coming from ca 75% when I left it.

The last couple of weeks I have seen this about a dozen times. The screen stays on, at a book or in the home screen or whatever and it seems to drain about 10% or more of power per hour. I don't read pdf's. What I am reading is a rather large (>900 pages) epub. When I resume reading that epub it takes very long to go to the page I was reading (about page 170). Normally I can put the device into sleep mode and then battery life is normal as in v1. I have no clue for the moment what triggers the inability to go to sleep mode by itself. But it certainly is a bug in v2 firmware.

[CoolDragon]

I have noticed this too. So I am wondering if logging the running processes every, say, minute might help tracing this issue.

See my post https://www.mobileread.com/forums/showthread.php?t=81903 for the script of doing this.

[Shaggy]

Sounds like there's still a bug with ePub documents. I thought there was also one with v1 where it was calculating page numbers and got stuck in some state where it wouldn't sleep correctly. Might be it still needs some more tweaking in the code.

[ErikG]

Just to be complete:
I reported a drain of the battery with a large epub open.
Yesterday I left the device with a rather small epub (ca 200pages) open.
This morning the page was still displayed but the battery was completely dead. The dr800 responded to nothing I did and needed charging for some ten minutes before it responded to the on/off switch and started to show that it was Charging.

So there seems to be difficulty in starting the sleep mode automatically.

[HansTWN]

Originally Posted by ErikG

Just to be complete:
I reported a drain of the battery with a large epub open.
Yesterday I left the device with a rather small epub (ca 200pages) open.
This morning the page was still displayed but the battery was completely dead. The dr800 responded to nothing I did and needed charging for some ten minutes before it responded to the on/off switch and started to show that it was Charging.

So there seems to be difficulty in starting the sleep mode automatically.

I had a Calibre newspaper open. When I looked this morning the page was still displayed and the battery went from fully charged (just recharged it last night) to half empty. This seems to be a random occurance. PDF, EPUB, Newspaper Direct. Happens with everything, but not always.