A:Answer Hi Rose, the MED3500FW required electrical supply is based on local Codes, 3- or 4-wire, single phase, 120/240 volt, 60 Hz, AC only electrical supply (or 3- or 4-wire, 120/208 volt electrical supply, if specified on the serial/rating plate) on a separate 30-amp circuit, fused on both sides of the line. Connect to an individual branch circuit. Do not have a fuse in the neutral or grounding circuit. Additional information can be found in the Installation guide: http://bit.ly/2khEj1K