SPECIFICATIONS
Part No.: IS200EPDMG1AAA
Manufacturer: General Electric
Country of Manufacture: United States of America (USA)
Temperature: 0 to 60 °C
Product Type: Exciter Power Distribution Module
Availability: In Stock
Series: EX2100
Functional Description
IS200EPDMG1AAA is an Exciter Power Distribution Module developed by GE. It is a part of EX2100 excitation system. Exciter Power Distribution Module (EPDM) serves as a dedicated power supply unit for the exciter's control, I/O, and protection boards. This crucial component is securely mounted on the side of the IS200EPBP Exciter Power Backplane (EPBP), forming an integral part of the excitation control infrastructure.
Power Sources and Input Handling
- Receives its primary power input, a robust 125 V dc supply, directly from the station battery. Additionally, it offers a provision for backup power with one or two 120 V ac inputs. All power inputs are meticulously managed through a board-mounted terminal block (TB1) and undergo thorough filtration to ensure stability and reliability.
- Each ac power supply undergoes rectification to transform it into a 125 V dc output using external Ac to Dc Converters (DACAs). The resulting dc voltages, designated as P125V and R125V, are diode-coupled through external diodes.
- These voltages are center grounded and typically maintained at +62.5 V and -62.5 V to ground. Chassis grounding and safety grounding are further ensured through four dedicated board mounting holes.
External Connections and Integration
- Two 12-plug connectors, JDACA1 and JDACA2, facilitate the connection of ac power sources from the terminal block (AC1 and AC2) to the external DACA 1 and DACA 2. These connectors efficiently return the DACA outputs to the 125 V dc lines (P125 and R125).
- This meticulous external connection design ensures a seamless integration of the power distribution system, enhancing overall reliability.
Individual Power Outputs and Board Distribution
- Features individual power supply outputs for each exciter board, each equipped with a fuse, an on/off toggle switch (except for the EXTB board), and a green LED indicator signaling power availability. These outputs are tailored to supply power to up to three Exciter Gate Pulse Amplifier Boards (EGPA), the Exciter Terminal Board (EXTB), and three Exciter Power Supply Modules (EPSM) serving three controllers.
- A dedicated connector is allocated for each output, intricately wired to the EPBP for systematic and efficient power distribution. This design ensures that each exciter board receives the requisite power supply with precision and reliability.
Replacement Procedures
- De-energize the Exciter: Begin the replacement procedure by ensuring that the exciter is completely de-energized. Refer to the EX2100 Installation and Startup Guide (GEH-6631) for comprehensive de-energizing procedures, and strictly adhere to all local lock-out and tag-out practices.
- Electrical Circuit Testing: Open the control cabinet door and employ equipment designed for high voltages to test all electrical circuits before any physical contact. This crucial step is necessary to guarantee that power is entirely off before proceeding with the replacement.
- Record and Set Switch Positions: Record the positions of all switches on the module. Set all switches to the OFF position. This documentation ensures accurate restoration of the switch configurations during the replacement process.
- Cable Disconnection:Carefully disconnect all cables by pulling each cable connector loose from the board. Confirm that each cable is labeled with the correct connector name, as marked on the board, to simplify the reconnection process. Exercise caution to avoid dropping any mounting hardware into the equipment, as this could lead to damage or personal injury when power is reapplied. TB1 is a pluggable terminal board; do not remove individual connections from the terminals. Ensure that the 125 V dc and 120 V ac external power connections are de-energized before removing the terminal board.
- Terminal Board Removal: Remove the terminal board by unscrewing the captive screws at each end while keeping the individual connections intact.
- EPDM Module Removal:Remove the seven mounting nuts that secure the metal standoffs, and carefully take out the module.
- New EPDM Module Installation: Position the new module in the same orientation as the original one and secure it to the metal standoffs using the seven nuts removed in step 5.
- Switch Verification and Fuse Check:Verify that all switches on the new module are set to the OFF position. Check that all fuses are present and in good condition.
- Cable Reconnection:Reconnect all cables that were previously disconnected from the module.
- Terminal Board Reinstallation: Position the terminal board (with the individual connections intact) in the same orientation as when it was removed. Press it into the plug on the new module, and tighten the mounting screws at each end.
- Switch Configuration Restoration:After power is reapplied, set all switches to the positions recorded in step 3, referring to the documentation made before the replacement.
- Finalization and Cabinet Closure: Close the control cabinet door, completing the replacement process with due diligence.
Switches
- SW1: Controls power to EGPA#1 board.
- SW2: Manages power distribution to EGPA#2 board.
- SW3: Governs power supply to EGPA#3 board.
- SW4: Regulates power to EPSM module master #1.
- SW5: Oversees power distribution to EPSM module master #2.
- SW6: Controls power supply to the EPSM module controller.
- SW7: Reserved spare switch for potential future usage or system expansion.
Steady-state Current
- Each EGPA board draws a steady-state current of 0.9 A, calculated as the worst-case scenario, resulting in a total current requirement of 2.7 A for all three boards combined.
- The EXTB board consumes 0.1 A individually, with an additional 2 A for its operation, summing up to a total current demand of 2.1 A.
- The EPSM module M1PS necessitates 2.8 A of current individually, based on the worst-case calculation, contributing to a total current consumption of 2.8 A.
- Similarly, the EPSM module M2PS requires 2.2 A of current per module, leading to a cumulative total current of 2.2 A.
- The EPSM module CPS draws a steady-state current of 1.8 A as per the worst-case calculation, resulting in a total current requirement of 1.8 A.
- Lastly, the spare module requires 1.8 A of current individually, contributing to a total current demand of 1.8 A.
The WOC team is always available to help you with your EX2100 requirements. For more information, please contact WOC.
Frequently Asked Questions
What is IS200EPDMG1AAA?
It is an Exciter Power Distribution Module developed by GE under the EX2100 series.
How is the AC power supply transformed into a DC output in the Exciter Power Distribution Module?
Each AC power supply undergoes rectification through external AC to DC Converters (DACAs). This process converts the alternating current (AC) into a direct current (DC) output suitable for powering the exciter control, I/O, and protection boards.
What are the resulting DC voltages after rectification?
The resulting DC voltages are designated as P125V and R125V. These voltages are maintained at approximately +62.5 V and -62.5 V to ground, respectively.
How are the P125V and R125V voltages coupled to the system?
The P125V and R125V voltages are diode-coupled through external diodes. This ensures a unidirectional flow of the DC voltages, contributing to the stability and reliability of the power supply.
What is the significance of center grounding in DC voltages?
The DC voltages, +62.5 V and -62.5 V, are center grounded. This means that the midpoint between the positive and negative voltages is connected to the ground. Center grounding helps maintain a balanced and stable electrical reference point in the system.
