Modular switching contactor arrangement (180, 190) for use in a safety-oriented application, comprising: a first and a second switching contactor module (10, 11; 240, 260), which each have the following features: a switching contactor (60; 261-265; 241-245) arranged in a housing (20; 300-304; 310-314) and first electrical terminals (43-45; 273-275; 257-259) and second electrical terminals (40- 42; 270-272; 250-252), one normally open contact (61-63; 263-265; 243-245) of the switching contactor being arranged in each case between each first electrical terminal (43-45; 273- 275; 257-259) and each second electrical terminal (40-42; 270-272; 250-252), the housing (20; 300-304; 310-314) having a rectangular base face (21; 300; 310) of a first predetermined width, two side faces (22, 26; 304; 314), which are arranged mutually parallel and at a distance from one another that corresponds to the first predetermined width of the housing (20; 300-304; 310-314), and a first terminal face (24; 303; 311) and a second terminal face (25; 301; 313), which oppose one another, have the first predetermined width and are each arranged perpendicular to the base face (21; 300, 310) at least in portions, the first electrical terminals (43-45; 273-275; 257-259) being arranged on the first terminal face (24; 303; 311) and the second electrical terminals (40-42; 270-272; 250-252) being arranged on the second terminal face (25; 301; 313), a coupling module (70; 230) of a second predetermined width substantially equal to the first predetermined width, the coupling module (70; 230) having an electrical coupling device comprising first electrical terminals (81-83; 290-292) and second electrical terminals (81'-83'; 293-295) that are formed and arranged for electrical coupling to the first electrical terminals (43-45; 273-275; 257-259) of the first and second switching contactor module (10, 11; 240, 260) respectively, the first switching contactor module (10, 240) and the second switching contactor module (11; 260) being electrically and mechanically couplable by means of the coupling module (70; 230) in such a way that, in the mounted state, the normally open contacts (61-63; 243-245) of the first switching contactor module (10; 240) and the normally open contacts of the second switching contactor module (11; 260) are electrically connected in series in each case and the construction width of the switching contactor arrangement (180, 190) is substantially equal to the first and second predetermined width respectively, characterized in that the first and second switching contactor module (10, 11; 240, 260) comprises each mechanical connecting elements (162, 163) for mechanically connecting to mechanical connecting elements (160, 162) of the coupling module (70, 230). a first and a second switching contactor module (10, 11; 240, 260), which each have the following features: a switching contactor (60; 261-265; 241-245) arranged in a housing (20; 300-304; 310-314) and first electrical terminals (43-45; 273-275; 257-259) and second electrical terminals (40- 42; 270-272; 250-252), one normally open contact (61-63; 263-265; 243-245) of the switching contactor being arranged in each case between each first electrical terminal (43-45; 273- 275; 257-259) and each second electrical terminal (40-42; 270-272; 250-252), the housing (20; 300-304; 310-314) having a rectangular base face (21; 300; 310) of a first predetermined width, two side faces (22, 26; 304; 314), which are arranged mutually parallel and at a distance from one another that corresponds to the first predetermined width of the housing (20; 300-304; 310-314), and a first terminal face (24; 303; 311) and a second terminal face (25; 301; 313), which oppose one another, have the first predetermined width and are each arranged perpendicular to the base face (21; 300, 310) at least in portions, the first electrical terminals (43-45; 273-275; 257-259) being arranged on the first terminal face (24; 303; 311) and the second electrical terminals (40-42; 270-272; 250-252) being arranged on the second terminal face (25; 301; 313), a coupling module (70; 230) of a second predetermined width substantially equal to the first predetermined width, the coupling module (70; 230) having an electrical coupling device comprising first electrical terminals (81-83; 290-292) and second electrical terminals (81'-83'; 293-295) that are formed and arranged for electrical coupling to the first electrical terminals (43-45; 273-275; 257-259) of the first and second switching contactor module (10, 11; 240, 260) respectively, the first switching contactor module (10, 240) and the second switching contactor module (11; 260) being electrically and mechanically couplable by means of the coupling module (70; 230) in such a way that, in the mounted state, the normally open contacts (61-63; 243-245) of the first switching contactor module (10; 240) and the normally open contacts of the second switching contactor module (11; 260) are electrically connected in series in each case and the construction width of the switching contactor arrangement (180, 190) is substantially equal to the first and second predetermined width respectively, characterized in that the first and second switching contactor module (10, 11; 240, 260) comprises each mechanical connecting elements (162, 163) for mechanically connecting to mechanical connecting elements (160, 162) of the coupling module (70, 230).