SPECIFICATIONS
Part Number: IS200EDEXG2A
Manufacturer: General Electric
Series: EX2100e
Product type: Exciter De-Excitation Control Board
Manual: GEI-100466
Availability: In Stock
Country of Manufacture: United States (USA)
Functional Description
IS200EDEXG2A is an Exciter De-Excitation Control Board designed and developed by GE. It is a part of EX2100e control system. The main board in the de-excitation module is the Exciter De-Excitation control board. When an emergency shutdown occurs and the field breaker or contactors open, this module removes stored energy from the generator field. To ensure operation in the event of a power outage, it includes SCR firing, conduction sense feedback, and voltage retention. EMIO initiates de-excitation.
Features
- The board activates the 41dc contactor (MDA/MDB) or breaker and then sends de-excitation signals from the auxiliary contacts to the SCR firing circuits. EDEX boards are classified into two types. Group 1 is for SCR de-excitation, while Group 2 is for diode de-excitation. The main board in the de-excitation module is the product. When an emergency shutdown occurs and the field breaker or contactors open, this module removes stored energy from the generator field. In the event of a power outage, it provides SCR firing, conduction sense feedback, and voltage retention to ensure operation. EMIO starts the de-excitation process on the board.
- Voltage Hold Up Circuit It retains voltage on the positive and negative 24 V DC lines so that the SCR can be activated in the event of a total power outage. The voltage hold-up circuitry also provides voltage for wetting the external de-excitation contacts. This ensures that the firing command is available for de-excitation in the event of a power outage.
- Hall Effect sensors are used to detect current in the field circuit. A mechanical ring couples magnetic flux to the sensors on the board's top edge. Separate circuits detect bi-polar current flow in sensor circuits 1 and 2.
- The current sense signals M1 and M2 are sent to EXTB and then to control. The mechanical ring is configured to detect unidirectional current flow in diode de-excitation applications. Two red LEDs indicate the status of both current sense circuits. When current flow is detected, the indicators illuminate.
Replacement Procedures
- Verify that the panel in which the board is located has been de-energized.
- Open the auxiliary cabinet door and check any electrical circuits for power before touching them.
- Carefully disconnect all cables from the board by doing the following:
- To facilitate reconnection, ensure that all cables are labeled with the correct connector name (as marked on the board).
- Disconnect all of the board's cables and the stub-on wire jumper from connector E1A, leaving the other wire jumpers in place.
- Remove the conduction ring (flux concentrator) that sits on top of the Hall Effect sensors.
- Remove the EDEX board by opening the PEM Snap Top fasteners that hold it to the intermediate mounting panel.
- Arrange the wire jumpers on the replacement board in the same order as they were on the old board, and ensure that jumpers JP1 - 6 are in the same position.
- Place the replacement EDEX board in the same location on the mounting panel as the one that was removed, and secure it with the Snap Top fasteners.
- Install a new conductor ring.
- Reconnect all cables to the EDEX board and the wire jumper to E1A as labeled, and ensure that cables are properly seated at both ends.
- Close the door to the auxiliary cabinet.
WOC is happy to assist you with any of your GE requirements. Please contact us by phone or email for pricing and availability on any parts and repairs.
FREQUENTLY ASKED QUESTIONS
What is IS200EDEXG2A?
It is an Exciter De-Excitation Control Board designed and developed by GE.
What does the board do?
Removes stored energy from the generator field when an emergency shutdown occurs and the field breaker or contactors open. It also provides SCR firing, conduction sense feedback, and voltage retention to ensure operation in the event of a power outage.
How does the board initiate de-excitation?
The board initiates de-excitation through EMIO (Excitation Control Module Interface Output).
What are the two types of EDEX boards?
The boards are classified into two types: Group 1 is for SCR de-excitation, while Group 2 is for diode de-excitation.
