RTS Transfer switch. Service entrance rated, NEMA 3R, CSA service rated compliant. RTS transfer switches are integrated with the R-Series digital controller and operate only with units 7 to 60 kW. This model features a water-proof NEMA 3R enclosure that is service entrance rated. Also, the switch phase and voltage must match that of the generator it is connected to. With the RTS transfer switch, you can choose to cover every circuit all the time or only essential circuits depending upon the generator with which it is paired. RTS open transition transfer switches are ideal for residential, commercial and light industrial applications.