IPad-3 Charging from my Laptop through USB cable

[rajatnanda]

Hi, my IPad-3 does not get charged from my Laptop, whereas, it only gets charged through 10W power cable. I would appreciate if anybody could give me the reason for not charging. Thanks

 

[KevinJS]

USB does not supply sufficient power to charge the iPad. It will charge very slowly, but the charging symbol will not show up.

 

[KevinJS]

I should add that USB3.0 supposedly supplies enough power, but my computer only has USB2.0, so I can't vouch for that.

 

[rajatnanda]

hi Kevin, thx for yr advice. when I charge my IPad thru my Laptop, it just write on the top right corner Battery sign 'Not Charging'. It means, it does not get charged.

 

[KevinJS]

You will always see "Not Charging" when the iPad is plugged into USB2.0, however it will charge sufficiently to maintain charge, or at least slow down the discharge. Eventually, it might even fully charge, but it is going to be a slow process, even if you have the screen turned off.

 

[rajatnanda]

thx, Kevin.

 

[LeonKaiser]

I should add that USB3.0 supposedly supplies enough power, but my computer only has USB2.0, so I can't vouch for that.

USB 3.0 port here. But not charging. Any luck with others here with USB 3.0?

 

[Dougsap]

When charging using USB 3.0 from my HP DV7 laptop:

• SYS Activity Manager Plus indicates that it IS Charging
• The screen battery indicator says "Not Charging"

SYS Activity Manager Plus (for Memory, Processes, Disk, Battery, Network, Device Stat & Performance Monitoring) is one of the relatively few paid apps that I have bought yet (and well worth the 99 cents).

 

[ckmerc]

There is an adapter cable for cheap on amazon that "upgrades" to allow for USB 3.o charging.....works with stock ipad cable. $7

BoxWave iPad Charging Adapter, Allows You To Charge Your iPad 3/iPad 2/iPad on ANY Computer or USB Hub for Compatibility With Generic Chargers

Works great

 

[LeonKaiser]

When charging using USB 3.0 from my HP DV7 laptop:

[*]SYS Activity Manager Plus indicates that it IS Charging
[*]The screen battery indicator says "Not Charging"
<img src="http://www.ipadforums.net/attachment.php?attachmentid=19280"/>

SYS Activity Manager Plus (for Memory, Processes, Disk, Battery, Network, Device Stat & Performance Monitoring) is one of the relatively few paid apps that I have bought yet (and well worth the 99 cents).

Hmmm. Interesting. Does the battery percentage increase over time?

 

[iDeviceGuru]

Hi, my IPad-3 does not get charged from my Laptop, whereas, it only gets charged through 10W power cable. I would appreciate if anybody could give me the reason for not charging. Thanks

USB ports don't produce a high enough output voltage for the iPad to recognise a charge, all the USB port is really for is the transferring of data, USB 3.0 is the faster that 2.0 for obvious reasons, think about it this way, the iPad has a 11,000 mAh battery, most laptops are around the 15,000-25,000 mAh range, with your laptops charger input being about 5v the laptop would loose charge almost instantly trying to charge an iPad.

The iDevice Guru

 

[Gabriel1]

USB ports don't produce a high enough output voltage for the iPad to recognise a charge, all the USB port is really for is the transferring of data, USB 3.0 is the faster that 2.0 for obvious reasons, think about it this way, the iPad has a 11,000 watt battery, most laptops are around the 15,000-25,000 watt range, with your laptops charger input being about 5v the laptop would loose charge almost instantly trying to charge an iPad.

The iDevice Guru

I could be wrong but I think that you are confusing mAh with Watts?

The Archangel

 

[iDeviceGuru]

I could be wrong but I think that you are confusing mAh with Watts?

The Archangel

Indeed you are correct, I just noticed this as well! I was just posing on a topic to do with watts and just got mixed up, thanks tho!

 

[Dougsap]

Hmmm. Interesting. Does the battery percentage increase over time?

To answer your question, I did an experiment.

I plugged my New iPad with 64% battery life indicated into my USB 3.0 port. I changed the power settings on my laptop to not 'go to Sleep'.

After 5 hours charging on USB 3.0, the Battery Indicator showed 79% (or an increase of 3% per hour).



So, a very rough estimate of how long a full charge would take is 30 to 33 hours.

Conclusions:

• Recharging on USB 3.0 is slow (no surprise)
• SYS Activity Manager Plus' estimated recharge time is not correct for USB 3.0 charging (no surprise)

 

[LeonKaiser]

To answer your question, I did an experiment.

I plugged my New iPad with 64% battery life indicated into my USB 3.0 port. I changed the power settings on my laptop to not 'go to Sleep'.

After 5 hours charging on USB 3.0, the Battery Indicator showed 79% (or an increase of 3% per hour).

<img src="http://www.ipadforums.net/attachment.php?attachmentid=19350"/>

So, a very rough estimate of how long a full charge would take is 30 to 33 hours.

Conclusions:


[*]Recharging on USB 3.0 is slow (no surprise)
[*]SYS Activity Manager Plus' estimated recharge time is not correct for USB 3.0 charging (no surprise)

That's great. Now we have solid proof that USB 3.0 does charge the new iPad.

I did the same thing you did, this time with USB 2.0. The new iPad indicated "not charging," but after 1 hour and with the screen turned off, i got a 5% increase, from 35% to 40%.