Siemens 3RH1911-1HA22 Auxiliary Switch Block

The auxiliary switch block, also known as auxiliary contact block or switch block extension, from Siemens with type number 3RH1911-1HA22 is an electrical switching module for applications in electrical engineering. It has dimensions of 6 x 2 x 2 cm and weighs 0.05 kg. Auxiliary switch blocks serve to extend main switches or contactors with additional switching contacts, thus enabling control and signaling in complex systems. Typical applications are found in automation technology for signaling switching states and controlling complex systems, as well as in mechanical engineering for expanding control circuits for motors and valves.