We recommend using an extension cord, or some other 3 conductor power cable, that is at least 16 AWG. Cut the end of the cable off, and then strip to expose the three wires, typically white, black and green. Connect the black to L (called Live), white no N (called Nuetral), and green to the 3rd place from the right, that has the three line symbol for Ground. Our supply has a red switch on the side. When looking at the terminals, it will be on the right hand side of the supply. make sure that you have selected the proper input voltage with this switch. Either 220v (used mainly overseas) or 115V (for typical North American power)