APC's Automatic Transfer Switch (ATS) is a high-availability switch that has two input cords, one for each AC line, which provide redundant power to connected equipment. This product is designed to supply power to the load from a primary AC line. If that AC power becomes unavailable due to any reason, the ATS will automatically begin sourcing power from a secondary AC line. The transfer time from one line to another is seamless to the connected equipment. The ATS can withstand 0 to twice the nominal input voltage while preventing any possibly damaging transients or gaps in output voltage from reaching the connected equipment. Use APC's MasterSwitch series or rack-mount power distribution units (PDUs) in conjunction with the ATS to fulfill your individual power requirements.