Technical Specifications Basic Identification Brand: Alstom / Areva T&D Full Model Code: MMLG02R1AA0001E Series: MMLG02 Voltage Monitoring Relay Main Functions: Overvoltage / Undervoltage / Voltage Unbalance Protection Rated Monitoring Voltage: 110 VAC, 50Hz Enclosure Type: Standard Size 2 cabinet flush mount housing Application: MV substation busbar supervision, railway traction power grid, generator excitation cabinet, transformer control panel Electrical Operating Parameters Nominal Monitoring Voltage (Vn): 110 VAC, 50 Hz Overvoltage Adjustment Range: 110% ~ 140% × Vn Undervoltage Adjustment Range: 70% ~ 95% × Vn Time Delay Setting: 0.1s ~ 10s independent adjustable delay for OV & UV Reset Threshold: OV reset ≤102%Vn; UV reset ≥102%Vn Coil Power Consumption: ≤7.5 VA under rated voltage Continuous Allowable Input Voltage: 80% ~ 115% Vn long-term stable operation Contact Configuration & Load Ratings Contact Layout: 3 sets change-over contacts (3CO, 3NO + 3NC) Continuous carrying current per contact: 5 A AC Breaking Capacity (AC-15, 250 VAC): Max 1250 VA inductive load DC Breaking Capacity (DC-13, L/R=0.04s, 110 VDC): Max 330 W trip coil load Momentary make & carry capacity (0.2s pulse): 30 A peak Contact Material: Silver alloy anti-welding contacts Mechanical Service Life: ≥10,000,000 cycles without load Electrical Service Life: ≥100,000 cycles under full rated breaking load Indication & Calibration Features Mechanical latched red trip flag, manual reset pushbutton on front panel Independent rotary adjustment knobs for voltage threshold and time delay Lockable transparent dustproof polycarbonate front cover Rear screw-clamp terminal block for voltage input and trip/alarm circuit wiring Mechanical & Installation Mounting Method: Flush panel mounting with standard Size 2 cabinet cutout Overall Dimension: H 180 mm × W 144 mm × D 210 mm Net Weight: ~1.55 kg Housing: Sealed industrial polycarbonate enclosure, dust and moisture resistant Environmental & Compliance Standards Operating Ambient Temperature: -20 ℃ ~ +70 ℃ Storage & Transport Temperature: -40 ℃ ~ +85 ℃ Relative Humidity: 5% ~ 95% non-condensing Vibration & Shock Test: IEC 60255-21-1 substation anti-vibration standard EMC Immunity: IEC 61000-6-2 industrial electromagnetic compatibility Compliance Norm: IEC 60255-3 Measuring relays and protection equipment Certifications: CE marked, RoHS & REACH hazardous substance compliant