Siemens Industrial Controls 3RU2126-4DB0 Thermal Overload Relay 20-25A

The Siemens Industrial Controls 3RU2126-4DB0 Thermal Overload Relay is used for motor protection and has a current setting of 20- 25A in HVAC systems. The system protects motors against overcurrent conditions and phase failure that may lead to damage to the motors. It works through sensing the heat produced by the flow of current; high current results in bending of the bimetallic strip, leading to the opening of a contact that cuts off the power supply to the motor. Similar thermal overload relays are also used in industrial motor control.