Some users of the iPad have been getting a ‘Not Charging’ message while their iPad’s are plugged in to a computers USB port, this issue is confusing because it’s been happening on a variety of different machines and configurations. I actually had the error myself yesterday when I first plugged my iPad in. The issue is simply that the iPad has heftier charging requirements than iPods and iPhones, and some USB ports—especially those on older computers and most USB hubs—don’t provide enough power to charge the iPad during use. That doesn’t mean lower-power USB ports can’t charge the iPad at all,instead, whether they can charge the iPad’s battery—and how quickly—depends on how the iPad is being used.
So what’s going on here is that some lower power USB ports will deliver power to the iPad fast enough to charge it, especially while in heavy use. It’s tricky because it may actually charge it if you let the iPad go to sleep while it’s plugged in, but how will you know?
Here’s a summary of options for you:
- For the fastest charging, use the iPad’s included 10-Watt USB power adapter. This will fully charge the iPad in a few hours, even if you’re using the iPad at the same time.
- When connected to a high-power USB port—such as the ones on recent Macs and the iPhone Power Adapter—the iPad will charge, even during use, but more slowly. (We haven’t yet determined how much more slowly.)
- Some third-party powered USB hubs provide higher-power USB ports, but many don’t; similarly, the USB ports on most Windows PCs don’t provide this additional power.
- When connected to lower-power USB ports—those on older Macs, most Windows PCs, and most USB hubs (powered or unpowered)—the iPad’s battery is not charged while the iPad is awake, but is charged (again, slowly) when the iPad is asleep.
So to sum up, for best results, make sure that the iPad is plugged in to a powered USB hub or a USB port in the back of your computer rather than the front or top. When I got the message my iPad was plugged in to a powered USB hub on my desktop whose power connector had come unplugged, when I plugged it back in, the problem was solved.