Key Specifications Parameter Value Brand Schneider Electric / nVent (formerly Samwha EOCR) Series EOCR-3BZ2 Product Type Multifunctional Electronic Motor Protection Relay Model / Reference 3BZ2-WRCUHZ CT Type Window (Through-hole) type for easy installation without disconnecting power leads Current Measurement Integrated window-type CTs Current Setting Range • Direct measurement: 0.5-60A (with integrated CTs) • With external CTs: Up to 960A (using CT with 5A secondary) Control Voltage U: 100-240VAC/DC (wide range) Frequency 50/60 Hz (power circuit) Suitable for variable frequency drive applications Protection Functions • Overcurrent (Overload) • Undercurrent (Underload) • Phase Loss / Open Phase • Phase Reversal (Reverse Phase) • Phase Unbalance / Imbalance • Locked Rotor (Stall) at Start and Run • Earth Fault (Ground Fault) • Jamming • Mechanical jam Measurement Accuracy High precision (typically ±1%) Time Delay Settings • Start Delay (D-TIME): 0-200 seconds • Trip Delay (O-TIME): 0.2-120 seconds (definite) or 1-30 Class (inverse/thermal) • Undercurrent Trip Delay (U-TIME): 0.5-120 seconds • Earth Fault Trip Delay (E-TIME): 0.1-10 seconds Output Contact Configuration R-type: "Non-Fail-Safe" operation (contacts do not change state when relay is powered on/energized) Output Contacts Multiple independent relay outputs (typically 2-3) for trip and alarm functions Contact Rating: 3A / 250VAC resistive Reset Mode Manual (Instant) / Electric (Remote) / Auto selectable Communication Modbus RTU protocol, RS-485 interface Display / Indication • Digital display (7-segment LED) for real-time current values • Fault cause indication • LED indicators for operational status • Current amplitude bar graph Monitoring Functions • Real-time 3-phase current display • Cyclic display of currents • Fault recording with cause storage (last 3 faults) • Operating time accumulation • Self-diagnosis function • Motor running time display • Number of starts counter Mounting 35mm DIN Rail / Panel mount Special Features • High accuracy measurement • Records last 3 faults with detailed information (cause, current values) • Separate display unit option available • PC parameter setting capability via dedicated software • Restart limit function • Phase/Neutral load protection selectable Standards IEC 60947-4-1, UL, CSA Rated Operational Voltage (Ue) Up to 690V AC (dependent on external CT rating) Rated Insulation Voltage (Ui) 600V AC (UL/CSA) / 690V AC (IEC) Rated Impulse Withstand Voltage (Uimp) 6 kV Degree of Protection IP20 (relay body) / Front panel sealed Operating Temperature -20°C to 60°C Storage Temperature -30°C to 80°C Power Consumption Ultra-low consumption (typically <3W) Dimensions (W x H x D) Compact design for 35mm DIN rail mounting Weight Approximately 0.3 kg Terminal Wiring Screw clamp terminals for solid/stranded wires (1-2.5 mm²)