power drain when off

johnontheroad

Member
May 20, 2011
14
0
Seems like my A500 is using power when off. Any way I can tell what the parasite draw is, so I can turn it off?

Thanks,

== John
 

morrighu

Member
Jun 3, 2011
20
0
I don't know about your tablet specifically but I know that there are several apps on the market that will log what has been using your CPU. SEEPU is one that I use on my Samung Epic smart phone. It keeps a log of what has been using my CPU. Another good one is PhoneUsage which will track, among other things, background data transfer as transferring data can devour your battery life. I've seen apps run my smart phone so hard that it couldn't stay charged even when it was plugged in. The apps were draining the battery faster than the charger could charge it :/

For me the big culprits are:

  • Having my phone refuse to roam appropriately when Sprint's network isn't really available. If you're on the edge of your carrier's service area, there is an app called RoamControl that will let you force the roaming on a rooted device.
  • Apps in general as many want to operate continuously and transfer data constantly. Find them and either replace them with better behaved alternatives or use something like Titanium Backup to freeze and unfreeze them but again, that requires rooting the device. Your alternative is to uninstall and reinstall them as needed.
  • Facebook app as it wants to transfer data constantly.
  • Streaming music - again the constant data transfer.
  • Stock market apps - again they like to transfer data constantly
  • Sprint "stock" apps - (which I refer to as the Hillbilly Upgrade Package - NFL, NASCAR, Sprint TV, Qik Video, Sprint Media Hub, Sprint Hotspot) which all like to start up for no apparent reason but killing these requires rooting the device and using something like Titanium Backup to Freeze them. FYI, if you remove them, any updates to your Android platform will likely fail - at least they are known to fail with the Sprint smart phones.
  • Having my GPS on when not in use.
  • Using "live" wall paper
  • Having a screen saver running

HTH!
 

Icebike

Senior Member
Apr 28, 2011
1,523
186
Thanks for the tip about SEEPU and PhoneUsage.

On your list of items.... (above)

Live wallpaper is often given a bum rap:
It doesn't use any CPU unless you can see it. When using any other application, the wallpaper is not using any CPU. When your phone sleeps it doesn't use any either. So the big risk there is when you spend time in widgets with the wallpaper showing, or if you have a long sleep timeout causing it to stay on rather than go to sleep. Tablet users tend to have longer sleep timeouts than do the same users on their smartphones. So it makes sense not to use live wallpaper on your tablet.

GPS ON when not in use:
Unless you see the GPS symbol in the task bar the GPS is not "on". Just because its enabled, does not mean its on. Mine is always enabled, but then I don't have my phone or my tablet checking me in to facebook and all the other "stalk me" apps that constantly report my location. GPS never shows up on my list of battery hogs.

Most of the warnings about GPS use are for things like Google Maps and similar apps that keep the GPS on constantly. Just having it on causes no battery drain. Using the GPS constantly, and allowing the web browser to use your GPS can take chew up some battery, ESPECIALLY if you live/work in a large steel framed building away from windows. Just turn off location in the web browser settings and you will minimize almost all GPS battery use.

The biggest battery hog is the screen
Bar none, this is where the battery goes, But then that's why we own smartphones, so we live with it.

Uncontrollable:
The variable beyond the control of most users is Cell tower availability. The farther away the towers are, the more power your phone kicks out every few milliseconds as it checks in with the towers.

Of course this does not affect our Acers. But if your WIFI router is a long way away you get a similar problem as your Acer struggles to maintain connection by adjusting the power on the wifi transmitter.
 

morrighu

Member
Jun 3, 2011
20
0
The variable beyond the control of most users is Cell tower availability. The farther away the towers are, the more power your phone kicks out every few milliseconds as it checks in with the towers.

Of course this does not affect our Acers. But if your WIFI router is a long way away you get a similar problem as your Acer struggles to maintain connection by adjusting the power on the wifi transmitter.

If you can root the device, there are apps that will let you force the roaming, so not entirely beyond control. That said, you might want to take a long hard look at your data service contract and see if it allows for roaming and what any extra fees or charges for it might be. Right now, I think most of them are pretty ugly about it.

For example, I use an app on my Epic to force it to roam to another carrier's tower where it gets better signal and thus better battery life. I'm right on the edge and my phone flips into and out of roam non-stop which will burn through a full charge faster than frat house goes through a keg of beer.

You can also try updating the PRL (Preferred Roaming List) from your cell carrier. Sometimes that helps. Some times it makes it worse. In many cases they have financial incentives to keep you off certain networks which may able to provide you with better signal so they will code that into the PRL. Hypothetical example - Sprint and ATT. Sprint doesn't want their customers roaming on to ATT's network because they don't have a very equitable or favorable roaming exchange agreement. So Sprint will alter the PRL's to avoid any ATT towers. If you happen to be near an ATT tower and relying on the PRL to allow your phone to roam, it will flatly refuse to use the ATT tower and instead will burn itself up trying to find a Sprint tower or some other carriers tower where the contract is more favorable. That said, if you keep trying you may get a PRL that works well for you.

And another thought occurred to me for the OP - you said this started happening during the last week? I think I'd be finding what got installed during the past week and removing it to see if the problem goes away. You can always back it up before you uninstall it so that you can restore it if turns out to be a red herring.
 

Icebike

Senior Member
Apr 28, 2011
1,523
186
Sprint can't roam on at&t. at&t is gsm, sprint is cdma. 2 different networks.
Better example would be T-Mobile and At&T.

But its somewhat off topic since Acer Iconia's biggest roam decision is between you or your neighbors WIFI.

A lot of people make the mistake of setting their wifi sleep policy (wifi-disconnect policy) to "when screen off".
Your best bet is setting it to "never".

There are a lot of push-services in tablet-land, such as your Gmail, the Market updates, Google Talk, and any number of stalk-me social networking apps, some of which use push, but some use polling.

Those that use push open a socket and leave it open. When the socket becomes unreadable (time out or network layer dropped), they close it and open another socket. So your WiFi can be up and down continuously, which takes more power than just leaving it on.

You could suppress both push and poll data exchange by un-checking Background Data in Accounts and Sync. Then nothing gets service till you fire up the tablet and check for new stuff. I don't recommend it. I have a battery, and I intend to use it. I get nearly 24hrs on a full charge anyway.
 
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