How do I calculate the power output of a 12 unit trickle charger for mobile phones?
The inVue part uses 30 W. That label is to tell what you need to provide. However USB through 2.0 requires 500 mA, so it should be able to provide 12 ports x 5 V x 0.5 A/port = 30 W. That makes me think it is either 1) mislabeled and it will draw more or 2) won't be able to provide full power to all 12 devices.