Siemens 3RT1926-1BB44 is a three-phase power contactor designed for motor control in three-phase systems and is specified to be paired with the 3RH1921-1HA22 auxiliary contact block for expanded signaling. The 3RH1921-1HA22 provides four auxiliary contacts—two normally open and two normally closed—to support signaling and interlocking in control circuits. This pairing is a common configuration in Siemens Sirius drive- and automation-focused panels for starting and stopping three-phase motors in industrial applications.
