Undervoltage release for 3RV motor-protective breakers
The Siemens 3RV1902-1AV00-0FJ0 is an undervoltage release designed for the SIRIUS 3RV series of circuit breakers, covering frame sizes S00 through S3. It operates on a 400V AC, 50Hz control supply.
The 400V AC 50Hz rating defines the nominal coil voltage and frequency. This release mounts directly onto the side of the 3RV breaker — no separate wiring compartment needed. The dropout characteristic ensures the breaker opens when the control supply falls below roughly 70% of rated voltage, which is the standard undervoltage protection threshold for motor circuits per IEC 60947-2.