B-Line M22S-WRS3-MS4-A1 M22 Modular Three Position Key-Operated Selector Switch

No contact blocks are included. The M22S-WRS3-MS4-A1 ships with one key and one contact block mounting adapter, so you need to order the contact blocks themselves separately and snap them onto the adapter behind the panel. Budget for the number of N.O./N.C. blocks your control circuit needs on each of the three positions.

As shipped, the key is removable in the center position only, and the action is maintained, so the switch stays where you leave it. The removal positions can be changed in the field with coding adapters if you need the key trapped in one of the end positions or removable at more than one point.

It uses key code MS4. Order additional M22 key switches with the same MS4 code and one key operates all of them, which is how you standardize a line of control panels so maintenance carries a single key. A different code number means a different key.

Use the key version where the position change must be restricted, for example hand/off/auto on machinery, bypass of a safety or interlock, or locking a system out of automatic mode. A knob or lever selector does the same switching but anyone can turn it. This three-position key switch is maintained and non-illuminated, so it holds its position and gives no lamp feedback; if operators need visual indication, add a separate M22 indicator light.

Mechanical life is rated at 100,000 operations. For a station switched a few times a shift that is many years of service; for a switch cycled constantly every few minutes, plan on it as a wear item and stock a spare.

The bezel is black, which is the standard M22 modular finish, so it lines up visually with other black-bezel M22 pushbuttons, indicators and selector switches on the same panel face. All of them share the same 22.5 mm mounting hole.