How best to charge an iPad
I recently bought an iPad Air, which I am very pleased with, but I am having trouble getting it to recharge properly. Often, when I plug it into my iMac it will show that it isn’t actually charging at all. On my computer at work, it charges, but only very slowly. I can charge it really quickly from the mains, of course, but I don’t want to have to carry the adapter with me everywhere. Am I doing something wrong? Why provide a USB charging cable if it doesn’t work on USB? Sonya Carron The mains adapter provided with your iPad is the 12W model that supplies enough power to charge an iPad. The smaller, slimline plug adapter is the 5W model that is only rated for the iPhones and the first-generation iPad mini. This will charge the other iPads, but more slowly. It’s when you plug your iPad into the USB port of a computer that things get confusing. Most USB ports supply a maximum of 500mA. This isn’t enough to charge the iPad when it is in use, so it displays ‘Not Charging’ next to the battery icon. When the iPad is turned off (altogether or just its screen) it charges, albeit slowly. Macs with USB 3.0 can supply up to 900mA to Apple devices plugged into those ports, but only if the Mac is switched on and not in sleep mode.