Siemens Auxiliary switch on the front, 1 NO + 3 NCSiemens Auxiliary contacts are the perfect added component solutions to the main contacts. A key function of the Auxiliary contacts is they transfer data from the circuit to a logic controller, which consecutively gives instructions to the linked devices about whether to turn on or off. This instruction can also be executed remotely. The SIRIUS auxiliary contact block 3RH2911 1HA13 has one NO and three NC contacts. This makes the auxiliary contact