Overview
Manuals
Main Features
Operational Considerations
Features:
- Thermistor motor protection relay standard
- SIRIUS 3RN2 thermistor motor protection
- Standard evaluation unit with ATEX approval, open-circuit and short-circuit detection in the sensor circuit
Thermistor motor protection relay standard evaluation unit 22.5 mm enclosure screw terminal 2 changeover contacts Us = 24 V AC/DC manual/remote RESET with ATEX approval 2 LEDs (ready/tripped) electrical isolation test/RESET button wire-break monitoring short-circuit monitoring
It is typically used in conjunction with a PTC (Positive Temperature Coefficient) sensor installed within the motor windings to provide direct and reliable protection against abnormal conditions such as overload, excessively high ambient temperature, or insufficient cooling.
The 3RN2011-1BA30 Siemens Thermistor motor protection relay may still be available for purchase and support from Moore Automated Company beyond End-Of-Life (EOL) by the manufacturer (OEM).
Siemens 3RN2011-1BA30 Thermistor motor protection relay datasheet(Datasheets), Link
Important Notice: Other accessories, manuals, cables, calibration data, software, etc. are not included with this equipment unless listed in the above stock item description. All prices are shown in USD.
The 3RN2011-1BA30 determines the motor status by measuring the resistance of the PTC sensor circuit. When the motor winding temperature is normal, the PTC resistance is low, and the relay remains engaged. Once the temperature rises to the preset trip threshold (the point where the characteristic resistance changes abruptly), the relay's internal logic circuit is quickly activated, resetting the output contacts. When the temperature cools below the reset point, the relay automatically resumes normal operation according to its automatic reset characteristic.
- Control Power Supply: Standard 24V AC/DC control power supply.
- Reset Function: Provides manual and remote reset options. Never set it to "automatic reset" in applications where an unexpected motor restart could result in personal injury or property damage.
- Safety Integration: Provides electrical isolation to protect sensitive downstream control components from high-voltage surges.
