Description
GE D20 EME 2400-21004
I. Basic Information
Model: D20 EME | Part No.: 2400-21004Brand: GE General Electric (USA) | Product Line: WESDAC D20/D200 substation RTU & integrated control platform.EME Definition: Ethernet + Memory Expansion main control board, the core communication processor card of D20 system.
Product Description: Rack-mounted extended CPU board for D20, a critical component of D20 substation monitoring unit and power RTU. It performs system logic calculation, large-capacity memory expansion, Ethernet networking and multi-protocol data forwarding to realize data exchange between field I/O and dispatching SCADA master station. It serves as standard spare part for power distribution automation and auxiliary control of power plants.
Mounting Specification: Standard pluggable installation on dedicated D20 rack slots via rear backplane bus connection; PCB form factor.Dimensions: 225(L)×135(W)×30(H) mm, Net Weight ≈0.42kg.PCB coated with industrial three-proof conformal coating, IP20 protection for cabinet installation; certified per UL and IEC power standards for grid access approval.
Support Configuration Software: GE D20 Config, Toolbox; supports offline logic programming, online program download and onboard fault diagnosis.
Onboard Hardware: 10/100Mbps auto-adaptive Ethernet port, RS232/RS485 serial ports, dedicated D20 backplane system bus, RUN/FAULT/COMM status LED indicators and high-capacity onboard Flash/RAM memory chips.
II. Technical Specifications
1. Main Controller & Memory Parameters
- Processor: 32-bit dedicated industrial power-grade chip supporting multi-task parallel processing
- Standard Memory: 8MB RAM + 16MB Flash onboard; maximum expandable to 16MB RAM + 32MB Flash after EME upgrade (Model 2400-21004 is fully upgraded variant)
- Program Scan Cycle: Logic cycle 2~10ms; fastest analog telemetry scan cycle 100ms, fully applicable for four remote functions (YT/YX/YK/YTn: telemetry, telesignalling, remote control, remote regulation) of power automation.
- Self-diagnosis: Hardware watchdog, backplane short-circuit detection and memory checksum verification; communication lockout with front-panel alarm upon hardware failure.
2. Communication Interface Specifications (Core Functions)
- Ethernet (RJ45): 10BASE-T/100BASE-TX, compliant with three mainstream power protocols: IEC61850, Modbus TCP and DNP3.0 TCP for interconnection with dispatching SCADA and DCS systems.
- RS485/RS232 Serial Ports: Modbus RTU, DNP3 Serial, IEC60870-5-101 for local connection with protection relays and smart field instruments.
- D20 Parallel Backplane Bus: Interconnects DI/DO/AI/AO I/O daughter cards inside the rack; maximum 16 I/O modules can be mounted on a single backplane.
3. Power Supply Specification
Rated Input: DC24V (wide input range:18~32VDC), total power consumption ≤7W. Onboard power isolation with surge & Level-3 EMC protection to resist severe electromagnetic interference in substation environments.
4. Environmental Specifications
Operating Temperature: -20℃ ~ +70℃; Storage Temperature: -40℃ ~ +85℃Humidity: 5%~95% RH non-condensing; Vibration resistance: 5g (5~500Hz), satisfying harsh working conditions of substation and power plant local control cabinets.
5. Supported I/O Expansion Capacity
With EME main controller, full-system maximum configuration of D20 is listed below:
- AI Analog Input: 64 channels (4~20mA / 0~10V, accuracy ±0.1% FS)
- DI Digital Status Input: 128 channels DC24V dry contact input with wire-break detection, response time ≤1ms
- DO Remote Control Output: 64 channels relay/transistor output; relay contact rating 5A@250VAC
- Pulse Counter: 32 channels, max input frequency 1kHz for energy pulse acquisition
III. Key Features
Core Upgrade Component for D20 Ethernet Refit
Original legacy D20 CPU has no onboard Ethernet. EME is the exclusive expansion card to add Ethernet communication and support IEC61850 / DNP3 TCP, the preferred spare for legacy substation RTU renovation.
Large-Capacity Memory Expansion
Abundant storage space for multi-setpoint configuration, fault oscillography data and millisecond-timestamped SOE (Sequence of Event) records.
Multi-Protocol Gateway Routing
Enables protocol conversion from serial-based protocols to Ethernet: IEC101 to IEC104, Modbus to DNP3 to realize cross-protocol interconnection of heterogeneous power equipment.
Hot-Swap Capability
Support live hot plug & replacement on identical rack slots without system power cut, improving online maintenance efficiency for substations.
Full-channel SOE Event Recording
Millisecond-level timestamp for status change events; fault data stored locally and actively uploaded to remote dispatching center.
IV. Operating Principle
DC24V rack power feeds EME controller via backplane bus;
Downstream Data Collection: EME polls rack DI & AI modules via D20 backplane bus to acquire digital status and analog field signals;
Logic Execution: Onboard CPU runs user-defined configuration logic including interlock protection, limit alarm and reactive power switching control;
Upstream Data Upload: Process data encapsulated per IEC104/DNP3/Modbus via Ethernet or serial ports and transmitted to SCADA dispatching station;
Downstream Remote Control: Remote command issued by dispatching center → parsed by EME → forwarded via backplane bus to DO output cards to drive on-site circuit breakers and contactors.
V. Application Fields
- Distribution Substation: RTU monitoring for 10kV/35kV switchgear stations and distribution automation terminals;
- Thermal & Hydropower Auxiliary Control: Station service cabinet monitoring and auxiliary equipment data aggregation;
- Oil & Gas / Chemical Substation: Auxiliary monitoring for plant power distribution SIS and UPS supervision;
- Legacy System Retrofit: Ethernet transformation for original non-networked D20 units by retrofitting EME communication board.
