Product Core Brief
- Model: D20MIC 10BASE-T 820-0756
- Brand: GE / GE Energy (legacy D20/D200 substation controller family)
- Series: GE D20 / D200 RTU Communication Expansion
- Core Function: 10BASE-T Ethernet communication module for GE D20/D200 substation controllers and RTUs, providing LAN connectivity for SCADA communication, remote monitoring, and protocol exchange.
- Product Type: Ethernet Communication Module
- Key Specs: 10BASE-T (RJ-45) Ethernet interface | 10 Mbps LAN | D20/D200 chassis compatible | Modbus / DNP3 / IEC protocol support | legacy substation design
- Condition: New Original / New Surplus
- Note: “820-0756” is a GE part/assembly number. The base product is the D20 MIC 10BASE-T Ethernet communication module for the D20/D200 substation RTU platform.
Key Technical Specifications
- Part Number: D20MIC 10BASE-T 820-0756
- Product Family: GE D20 / D200 Substation Controller Communication Module
- Function: Ethernet LAN communication interface
- Ethernet Interface: 10BASE-T (RJ-45), 10 Mbps
- Protocol Support: Modbus, DNP3, IEC 60870-5-101/104, IEC 61850 (system-dependent)
- Chassis Compatibility: GE D20 and D200 RTU/substation controller chassis
- Power Supply: Varies by chassis configuration; commonly 20–60 VDC or 100–300 VDC / 85–264 VAC
- Operating Temperature: -20°C to +60°C (reference value)
- Protection: IP20, industrial EMC compliance
- Typical Applications: Substation automation, RTU SCADA communication, remote monitoring, protocol conversion, legacy D20/D200 system maintenance, and network interface expansion
Product Introduction (No Fluff)
The GE D20MIC 10BASE-T 820-0756 is an Ethernet communication module for the GE D20/D200 substation controller and RTU platform. It provides a 10BASE-T (RJ-45) LAN interface, enabling the D20/D200 controller to communicate with SCADA systems, HMI stations, and other networked devices over standard Ethernet.
This module is typically installed in a D20 or D200 chassis to add network connectivity for remote monitoring, data acquisition, and protocol exchange. It supports common utility protocols such as Modbus, DNP3, and IEC standards, making it suitable for substation automation, remote terminal unit communication, and legacy GE Energy RTU upgrades. Because the D20/D200 controller family is now legacy, the D20 MIC 10BASE-T is mainly used for spare parts, system maintenance, and migration support.
The “820-0756” marking is a GE part or assembly number and does not change the module’s base function as a D20 MIC 10BASE-T Ethernet communication board.
Note: Some third-party listings describe “D20 MIC” as an SCR/thyristor power control module. For the GE D20 substation RTU context, the D20 MIC 10BASE-T is treated as a communication/ne
twork interface module. Verify the label and physical connector before installation.
QA & Testing SOP (Dynamic & Transparent)
For a legacy substation communication module, we verify identification, physical condition, connector integrity, and basic readiness before release.
- Part number verification: Confirm D20 MIC 10BASE-T and 820-0756 on the module label. Record revision, serial number, and date code where available.
- Visual inspection: Check the PCB, RJ-45 connector, mounting hardware, and backplane interface for corrosion, burn marks, or mechanical damage.
- Connector inspection: Verify the RJ-45 Ethernet port and backplane connector for bent pins, contamination, or poor contact.
- Chassis compatibility check: Confirm the module matches the target D20/D200 chassis slot and configuration.
- Firmware/configuration note: Where possible, record existing firmware or configuration references for traceability.
- Functional test limitation: Full functional testing requires a compatible D20/D200 chassis and SCADA environment; if not available, testing is limited to visual, electrical, and connector checks.
- ESD-safe packaging: Ship in anti-static bags with foam protection. Include part number, revision, and inspection status on the label.
Installation Pitfalls & Guide (Engineer to Engineer)
❗ Confirm chassis and slot compatibility. The D20 MIC 10BASE-T is designed for GE D20/D200 substation controller chassis. Do not install it in unrelated GE PLC or PACSystems racks.
❗ This is a legacy 10 Mbps Ethernet interface. It supports 10BASE-T only. Ensure the connected switch or network infrastructure supports 10 Mbps or auto-negotiation.
❗ Protocol settings are system-dependent. Modbus, DNP3, IEC 61850, and SCADA addressing must be verified against the existing D20 configuration.
❗ This is a legacy product. The D20/D200 controller family has been discontinued, with G500 or D20MX/D200MX recommended as alternatives. Use D20 MIC 10BASE-T mainly for maintenance, spare replacement, or migration projects.
❗ Do not assume universal power compatibility. Power requirements depend on the D20/D200 chassis configuration. Verify the installed power supply and backplane voltage before installation.
❗ Verify module identity. Some third-party sources describe “D20 MIC” differently. Always confirm the physical label, connector type, and chassis context before installation.
Replacement steps:
- Pre-install: Record chassis type, slot position, IP address, subnet mask, gateway, protocol settings, and SCADA communication parameters.
- Isolate: Follow substation or plant procedures before removing or inserting modules.
- Remove: Disconnect the Ethernet cable, then remove the module from the chassis without forcing connectors.
- Install: Seat the replacement D20 MIC 10BASE-T firmly, restore the Ethernet connection, and verify chassis recognition.
- Commission: Verify Ethernet link status, network connectivity, protocol communication, and SCADA data flow before returning to service.
Technical FAQ
What is the GE D20MIC 10BASE-T 820-0756? It is a 10BASE-T Ethernet communication module for GE D20/D200 substation controllers and RTUs, with 820-0756 as the GE part/assembly number.
Which Ethernet standard does it support? It supports 10BASE-T (RJ-45) at 10 Mbps.
Can it be used in PACSystems RX3i or RX7i? No. It belongs to the GE D20/D200 substation controller family, not the PACSystems RX3i/RX7i/PAC8000 families.
Is this module still in production? The D20/D200 controller family is legacy and discontinued. Availability is typically through surplus stock or spare parts channels.
What protocols can it support? It can support Modbus, DNP3, IEC 60870-5, and IEC 61850 depending on system configuration and software.
