The standard PoweredUSB power overcomes the limitations of the USB standard supports only +5 VDC 500mA (max). These values are sufficient for keyboards, cameras, etc.. But not for other devices that require more power and different voltages (printers, POS, etc). The standard is compatible with USB PoweredUSB but adds 2 pairs carrying power of 5V, 12V or 24V at a current up to 6A per socket (3A power per pair). PoweredUSB connector (Host-Side) has 2 lines of 4 pins each: the first to support USB data cable (type A) and the second that carries food (2 pins and 2 pins + V GND). This connector can be 3 colors depending on voltage: 5VDC gray to green to red to 12VDC and 24VDC.