This invention relates to electrical switching apparatus.  More particularly, it is concerned with electromagnetically operated switching apparatus employing convertible contact modules which operate in either a normally open or normally closed condition depending upon their mounting position. 
Electrical switching apparatus such as electromagnetic contactors for opening and closing a plurality of switches are well-known.  In order to provide versatility contactors of this general type frequently employ switch or contact modules which selectively may be changed to function in either the normally open or normally closed condition.  Certain contactors are designed to employ convertible contact modules which when placed in the contactor in one position provide a normally open switch, and when removed and replaced in a different position provide a normally closed switch.  With contactors of this type heretofore available, however, it was necessary to disconnect the external wiring in order to remove and convert a contact module.  Time was required to disconnect and reconnect the wiring, and in addition there was the possibility of making errors when reconnecting the external wiring.