Quick Sizing & Sourcing Snapshot
- Manufacturer: GE (General Electric)
- Part Number: IS200EDCFG1B
- System Platform: EX2100 / EX2100e Excitation Control (Mark VI/VIe)
- Hardware Type: Exciter DC Feedback Board (EDCF)
- Architectural Role: Measures DC Field Voltage and Current at the SCR bridge and converts signals to frequency/optical pulses for the EISB controller interface.
- Key Specifications: 1400V RMS Max Scale (G1B), DC Shunt Input (500mV), Fiber Optic Output (HCS/POF).
System Architecture & Operational Principle
The IS200EDCFG1B is an active signal conditioning board mounted in the Exciter Auxiliary Cabinet, distinct from the passive terminal boards like EACF. It sits at the physical SCR bridge level (or nearby), interfacing directly with high-current DC field wiring.
Upstream: It receives raw DC signals: Field Voltage (direct to E1 connector, – to SCR negative) and Field Current (via a DC Shunt, 500mV max, to P1 connector). The board uses Differential Amplifiers to condition these low-level signals, rejecting common-mode noise from the thyristor switching. It then drives a VCO (Voltage Controlled Oscillator) to convert the DC levels into frequency pulses.
Downstream: It transmits these pulses over Fiber Optic links (Connectors: CF OF for Current, VF OF for Voltage) to the EISB (Exciter ISBus Board) in the control rack. This fiber link provides total galvanic isolation (thousands of volts) between the high-power bridge and the low-voltage logic controllers. The “G1B” suffix indicates support for high PPT voltage scaling (up to 1400V RMS via jumpers), making it suitable for large generator exciters.
Core Technical Specifications
- Function: DC Field Voltage & Current Measurement (SCR Bridge Level)
- Voltage Input: E1 Connector (Field Voltage Neg/SCR Cathode), Scaled via Jumpers JP1-JP10 (140V to 1400V RMS)
- Current Input: P1 Connector (4-pin), Accepts DC Shunt signal (0-500mV Full Scale)
- Signal Conditioning: Differential Amp (Noise Rejection), VCO (Freq Conversion)
- Output Interface: 2x HFBR-1528 Fiber Optic Drivers (CF: Current, VF: Voltage)
- Fiber Types: POF (Plastic, 10m) or HCS (Hard Clad Silica, 90m) via JP7/JP8
- Power Input: J16 Connector (2-pin), Requires 24V DC External (PSOK LED monitor)
- Indicators: PSOK (Green = Regulated Power Good), Test Points (R26, R27, etc.)
- Isolation: Fiber Optic (Infinite Galvanic Isolation between Bridge and Rack)
- Environmental: 0°C to +60°C (Operational), Conformal Coated
