We recommend wiring the "Schurter Brand" Rotary switches we sell in a multi-axis "redundant" DPST (Double Pole / Single Throw) contact arrangement as shown in the following diagrams. The 110V position will be the ON position, and the 220V position will be the OFF position.
It is also Paramount that you avoid overheating the switch post terminals when you solder your sled power wiring. The recommended procedure for soldering is as follows:
RRC2+ Wiring
RRC3 Wiring