Confirmed: "Not charging" iPad does recharge

Just plugged my new iPad directly into a usb port on the back of my Mac Pro tower and it will not charge. Apple can spin the "high powered" thing all it wants but plugging one apple product into another should ALWAYS work. So now I have to have two cables coming to my desktop, one to charge the iPad (plugged in to wall) and another to be able to sync it. Maybe apple could come up with an A/B switch to handle the problem (just kidding, having this issue is really stupid).
Hello Apple hire some QA people already.

My battery was at 42% when I plugged my iPad in and it gave the "Not Charging" dialog. I left it plugged in over night and when I woke up it was at 41% so I actually lost a little bit of charge. It was plugged in to my Macbook Pro which is brand new also so I know it isn't the USB port. However when I switched doc cables (using the one for my iPhone) it worked like a charm. I suspect the problem is a combination of issues starting with the charging cables!

I just got my ipad on Friday so I am late to the party. I noticed it said "not charging" when I plugged it into my PC so I asked Google about it and found your most excellent article. I left it plugged in and the battery does indeed show more of a charge. I suspect that it would take forever to charge it fully but at least if the battery is low I don't have to worry about it dieing while hooked to my PC. I am using it with a laptop I will test it on a desk top too.

I notice with my blackberry even my netbook charges it when I tether and rather quickly too especially considering that when I tether I usually run the netbook on battery . . and the battery still lasts almost as long as the one in the ipad. I mention this becaise it is what I expected with the ipad and it is always good to have something for comparison.

Maybe it was a april fools joke and they forgot to update it =)

Make it is a april fools joke and they forgot to update it =)

they should call it "barely charging" or something like that.

It is a simple maths problem really. If you work out the ampage needed to charge, which is the current just use Watts divided by Volts which is 10W/5.1V as stated on the iPad plug charger. This means the ampage needed is 2.1Amps to charge the iPad.

Most normal USB ports output at 500mA or 0.5Amps hence abut a quarter of the current and therfore it will take longer to charge. They still output at 5Volts though, hence why the iPad eventually charges. Hope this helps people understand why there stuff sometimes takes longer to charge, check the ampage!

There's info elsewhere about this. Apparently some USB ports aren't powerful enough to charge the iPad. I notice that if I plug my iPad into my MacBook Pro's USB ports directly, I'll see "charging". If I use a USB hub connected to the MBP, I'll see "not charging". But whether I use the device or not, it will charge in both situations. It'll just charge slower is the USB port doesn't supply enough power.

A tangential note: When I set up iPad on iTunes, I had it plugged into a hub. When I tried plugging it directly into my MBP when I first saw the "Not charging" message, iTunes thought it was a different iPad and tried to set it up again. I switched back to the hub and things were fine. However, at some point, I started using the MBP's USB ports again and had no problems.

So the iPad has a number of quirks

I got a charge out of this story. I think I'm going to plug it.

What voltage does the iPad charge at? I've got a Freeloader Pro:

http://www.thinkgeek.com/gadgets/travelpower/beb8/

That has settings for 5.5V and 9.5V... Most normal gadgets charge at 5.5, and i'm afraid to increase it to 9.5 for fear of damaging my iPad...