Technical Specifications Basic Identification Brand: Alstom Areva, later GE Grid Solutions MiCOM series Model: MiCOM P990 Product Type: All-in-one Bay Control, Protection & Metering IED Application: MV feeder bays, distribution transformers, railway traction substation switchgear, industrial plant power distribution Auxiliary Power Supply Rated supply: Dual range DC 110 V / DC 220 V universal input Operating tolerance: 77–137.5 VDC (110V); 154–275 VDC (220V) Typical power consumption: ≤20 W under full load Surge withstand: Class III overvoltage category, 2kV surge pulse immunity CT / VT Measurement Inputs CT secondary rated: Switchable 1 A / 5 A, 50 Hz VT rated voltage input: 100 V AC phase-to-phase Input burden: CT < 0.7 VA per phase; VT < 1.0 VA per phase Measurement accuracy: Class 0.5S for current, Class 0.2 for voltage, power & energy Full Integrated Protection Functions Overcurrent & Earth Fault Protection Two-stage phase overcurrent: IDMT inverse curve + definite instantaneous trip Sensitive residual earth fault two-stage protection Thermal overload monitoring for cables & transformers Negative sequence unbalance protection for three-phase asymmetry faults Voltage & Frequency Protection Overvoltage / undervoltage / voltage unbalance supervision Overfrequency / underfrequency load shedding logic Loss-of-mains / loss-of-voltage grid islanding detection Supervision & Auxiliary Fault Logic Broken CT supervision, trip circuit continuous supervision Breaker failure protection, auto-reclose configurable sequences Neutral voltage displacement protection for unearthed MV networks Binary Input & Relay Output Interfaces Binary Inputs (DI): Up to 24 channels, DC110V signal level for breaker position, interlock, blocking, remote trip signals Relay Outputs (DO): Up to 12 forced-guided heavy-duty mechanical relays AC-15 rating: 250 VAC, 6 A resistive / inductive load DC-13 rating: 110 VDC, 3 A inductive trip coil load Contact mechanical life: ≥10,000,000 cycles unloaded; electrical life ≥100,000 full rated operations Recording & Data Storage Event log storage: Min. 1000 time-stamped fault & alarm records with millisecond precision Disturbance recorder: 80-cycle high-speed waveform capture for post-fault analysis Historical trend data: Storing voltage, current, power, temperature trending curves Non-volatile memory retains all settings & records without auxiliary power supply Multi-Communication Interfaces Rear RJ45 Ethernet: IEC 61850, IEC 60870-5-104, DNP3 TCP/IP Isolated RS485 serial port: Modbus RTU, IEC 60870-5-103 Front RS232 maintenance port: Local parameter configuration, firmware upgrade Dual redundant communication channels optional for critical traction substation applications Mechanical & Installation Mounting method: Standard flush panel mounting, unified industry cabinet cutout Front panel: Backlit color graphical LCD, multi-status LED array, lockable transparent cover for tamper prevention Wiring terminals: Rear screw-clamp terminal blocks for CT, VT, supply, DI/DO wiring Overall dimensions: H 172 mm × W 144 mm × D 230 mm Net weight: ~1.45 kg