Siemens 3UA50 00-1D Solid State Thermal Overload Relay

Siemens 3UA50 00-1D Solid State Thermal Overload Relay is a compact protection module designed to install with Siemens World Series motor starters to guard AC motors on 600 V circuits. It provides a current-setting range of 2 to 3.2 A, enabling precise overload protection matched to the motor’s running current, and is rated for operation up to 600 V. This assembled unit is intended for use with Siemens World Series contactors such as 3TF30, 3TF31, 3TF40, 3TF41, and the 3TB40/3TB41 families, integrating into starter assemblies to interrupt power when an overload is detected. Some listings describe the unit as delivered as a ready-to-install module with wiring connectors and terminals, and note a manual reset button for fault clearance. The 3UA50-00-1D designation places it in Siemens’ 3UA thermal overload family, a fixture of Siemens motor-protection schemes within World Series control gear.