The GE IS200EGDMH1AFG is an Exciter Ground Detector Module (EGDM) used in the GE EX2100 excitation control system, typically integrated with Mark VI turbine control systems.
Its main function is to detect ground faults (insulation leakage) in the generator field circuit, helping protect turbine generators from serious electrical damage.
In practical terms, it continuously monitors whether the generator field winding has unintended electrical leakage to ground, which is critical for preventing insulation failure and generator trips.
Technical Specifications
| Parameter | Specification |
|---|---|
| Module Type | Exciter Ground Detector Module (EGDM) |
| Series | GE EX2100 / Mark VI compatible |
| Function | Field ground fault detection and monitoring |
| System Role | Generator excitation protection module |
| Installation | EPBP (Exciter Power Backplane) rack |
| Detection Method | Injected test signal + leakage current measurement |
| Channels | 12 signal processing channels |
| Input Range | 4–20 mA |
| Output Signal | 0–20 mA analog output |
| Common Mode Range | ±5 V |
| Lead Resistance | Up to 15 Ω |
| Test Signal | ±50 V square wave injection |
| Signal Type | AC/DC field leakage detection |
| Operating Temperature | -30°C to +65°C |
| Storage Temperature | -40°C to +85°C |
| Mounting | Double-slot 6U rack module |
Physical Characteristics
| Item | Value |
|---|---|
| Dimensions | ~228 × 152 × 38 mm |
| Weight | ~0.3 – 0.6 kg |
| Form Factor | 6U double-slot VME-style board |
How It Works (Simple Explanation)
- The module injects a controlled test voltage into the generator field circuit
- It monitors any leakage current flowing to ground
- A sensing circuit compares expected vs. actual leakage
- The signal is converted into digital/analog output
- If leakage exceeds safe limits → alarm or trip signal is generated
This helps detect insulation problems before catastrophic failure occurs.
System Role
The IS200EGDMH1AFG is a protection and monitoring module, not a control processor.
It works with:
- EX2100 excitation controller
- DSPX control boards
- EXAM attenuator module
- Mark VIe turbine control system
It is often configured in:
- Simplex systems (1 EGDM)
- Redundant systems (3 EGDM: C, M1, M2 roles)
