ALSTOM DFI-150-0003

Technical Specifications

• Fixed Model Code: DFI-150 base hardware platform, 0003 fixed firmware variant for three-phase cable distribution networks
• Field Sensor Communication Interface: Isolated RS485 bus supporting 64 remote fault indicator sensors
• Three-Phase Analog Input: 0–5 A secondary CT current, 0–100 VAC residual voltage
• Fault Detection Logic: Phase short-circuit fault, single-phase earth fault, overload overcurrent fault, broken conductor fault
• Control Power Supply: 220 VAC / 24 VDC dual power redundant input
• Operating Ambient Temperature: -20 °C ~ +60 °C outdoor distribution cabinet range
• Protection Enclosure Rating: IP54 dust and splash water resistance

Functional Features

1. Synchronous data polling of all remote overhead/cable fault indicator sensors on distribution feeder
2. Real-time three-phase residual current and residual voltage earth fault vector calculation
3. Fault location distance calculation algorithm for medium voltage cable lines
4. Fault event time-stamp recording and non-volatile memory data storage
5. Upper system communication via Modbus TCP/RTU for distribution automation SCADA platform
6. Local audible and visual fault alarm output relay contacts

Performance Parameters

• Maximum supported feeder length coverage: 15 km medium voltage cable network
• Fault detection response latency: ≤ 15 ms for short-circuit fault trigger
• Non-volatile storage capacity: 1000 fault event records, data retention ≥ 10 years without power supply
• Current measurement accuracy: ±0.2% full scale CT secondary range
• Total module power consumption: 9 W under normal operating condition

Material Composition

• Outer enclosure: Die-cast aluminum alloy with outdoor anti-ultraviolet powder coating
• Internal circuit board: Conformal coated FR4 PCB resistant to humidity and dust
• Communication isolation: High voltage isolation optocoupler and signal transformers
• Alarm components: High decibel piezoelectric buzzer, red high-brightness fault LED array

Structural Characteristics

• Wall-mounted outdoor distribution cabinet installation structure with four corrosion-resistant mounting brackets
• Front transparent polycarbonate observation window for LED status indication without cabinet opening
• Lower compartment integrated sealed cable gland ports for all field sensor wiring entry
• Internal partition separates high-current CT wiring area and low-voltage communication circuit area

Working Principle

Advantage Highlights

• Outdoor wide temperature range design adapts to unconditioned roadside distribution cabinet environment
• Single module supports up to 64 distributed fault sensors covering long distribution feeders
• Built-in cable fault distance calculation eliminates manual line inspection after fault occurrence
• Dual redundant power input ensures continuous fault monitoring during single power supply failure
• IP54 sealed enclosure prevents outdoor rain splash and dust ingress circuit damage

Applicable Industries

Installation Requirements

1. Mount enclosure vertically on shaded outdoor wall, avoid direct long-term sunlight ultraviolet irradiation
2. Use armored shielded cable for all remote fault indicator RS485 communication wiring
3. Install dedicated lightning surge protection device at cable gland entry point of cabinet
4. Connect enclosure ground terminal to local distribution network protective earth electrode

Operation Precautions

1. Cut off both AC and DC dual power supplies before opening cabinet maintenance cover
2. Clear accumulated dust inside enclosure every 12 months to prevent circuit short-circuit
3. Do not install module in low-lying areas prone to rainwater flooding
4. Update internal fault algorithm firmware only via official ALSTOM dedicated service software
5. Test full fault simulation logic every 2 years per distribution grid operation specification