GE IS200EGDMH1ADF EGDM Exciter Ground Detection Module

Description

We have summarized a set of effective fault identification and handling methods.
1. When the data in the monitoring screen shows the following situations, it indicates that there is a problem with the control system. The microcomputer maintenance personnel should be notified immediately for repair, and the operator should come to the site for processing.
(1) Frequently changing data remains unchanged for a long time, and several or all data remains unchanged.
(2) In the control group screen, manual and automatic switching is not possible, or after manually inputting data, once confirmed, it returns to the original data and cannot be modified.
(3) In the trend graph screen, several trends remain unchanged as straight lines.
(4) In the monitoring screen, multiple data fluctuate significantly at the same time.

Determine whether the fluctuation data is a process related parameter. If it is a related parameter, notify the instrument and microcomputer personnel to check to see if a certain regulation system fluctuation has caused a change in the relevant parameters. At the same time, set the relevant regulation system to manual mode and adjust it on-site if necessary. In a water solution full circulation device, when the pressure of the urea synthesis tower is normal, it is l9.67MPa. If there is a sudden large-scale fluctuation, it will inevitably cause pressure fluctuations in the downstream medium and low pressure systems. This situation is due to the fluctuation of one of several related parameters causing changes in other parameters, not the failure of the control system itself. If there is no direct impact on each other in terms of fluctuation data technology, it may be due to a malfunction of a certain card in the microcomputer. Immediately set the relevant automatic adjustment system to manual adjustment, and if necessary, go to the site for adjustment. At the same time, notify the microcomputer and instrument personnel to inspect.

2. Check the operation status of the operation station. When a certain operation station crashes, the monitoring screen data does not refresh, and the adjustment screen does not work, check whether the alarm indicator light in the upper right system is normal, and check whether other operation stations are working properly. If it is normal, only that operation station has a problem. Notify the microcomputer maintenance personnel for repair. If the data from other operating stations remains unchanged, it indicates a malfunction in the system communication network. Immediately notify maintenance personnel to check the operation of the network equipment and repair it.

3. Observe the power outage situation of the operation station. If some operation stations suddenly do not display, it indicates that the UPS or mains power is off, and immediately notify the microcomputer maintenance worker for maintenance. If the operating station with electricity can monitor normally, it will not affect the normal adjustment of the control system at this time.

4. Pay attention to the situation where all control station equipment is powered off. As all control station equipment is powered by dual circuits, one UPS and one mains supply, the probability of this situation occurring is very low. When the control station is completely powered off, the two system alarm red lights on the monitoring screen light up, communication is interrupted, and all data is not refreshed. All self regulating systems are completely out of control, and the regulating valve will return to its initial state, with the air opening valve fully closed and the air closing valve fully open. At this point, emergency handling or parking should be carried out immediately, and the operation should be carried out on-site at the same time.

5. Pay attention to the situation where all operating stations are powered off. At this time, check whether the power indicator light of the control station is normal, and whether the card diagnosis indicator light is faulty. The red light and green light indicate that the card is working normally. If all of the above are normal, it can be confirmed that the control station is working normally and the automatic adjustment system is working normally. However, the operator cannot temporarily see the monitoring screen and cannot perform remote control operations on the site. Immediately notify the microcomputer maintenance personnel for maintenance, And conduct on-site monitoring.

6. When multiple self regulating systems are found to be malfunctioning and the self regulating valve position on the monitoring screen is in the fully open or fully closed position, immediately check the instrument air supply pressure. If the air supply pressure is less than 0.4MPa, it is abnormal. Check the air supply pipeline for blockage or leakage; If the gas source pressure is less than 0.2MPa, immediately perform an emergency shutdown. Turn all the self regulating systems on the monitoring screen to manual mode, adjust the valve position of the regulating valve to a safe position, notify the instrument technician to check the air source, and operate on site at the same time. Close the stop valves at both ends of the regulating valve and use a bypass valve for operation.

Conclusion: When DCS malfunctions, operators should master certain discrimination methods, identify problems early, and handle them appropriately to avoid or reduce the impact on process control.

Frequently asked questions about IS200EGDMH1A

How can the EXAM module be used together with the EGDM module?
One of the working methods of the EXAM module is to sense the voltage at both ends of the grounding resistor, and then send the signal to EGDM through a nine core cable.

If the IS200EGDMH1A board is used in a redundant system, how are the three boards configured?
If the EGDM board is used in a redundant system, the three boards will be configured as controller (C), master station 1 (M1), and master station 2 (M2). The configuration of each EGDM is controlled by a set of program pins on the P2 connector.

Is the IS200EGDMH1A model an active system?
Yes! As an active system, the EGDM model will apply voltage to the excitation circuit.

What is the role of the EGDM model?
The EGDM model has multiple functions, one of which is to detect the leakage resistance between any point in the ground excitation circuit and the generator.