Dear all, I work with GT frame 9E GE. We are having trouble resetting the "excitation trip" alarm and this situation does not allow us to synchronize. We have already tried to reset with the lockout relay on the protection panel and excitation panel, without success, it seems that the trip coil still remains energized. Are we doing it wrong? Is there another way to de-energize the trip coil so that we can reset it without causing damage to the equipment? We are a new O&M team and have never had the same experience, it is difficult to solve this problem.

 

You need to find out what is keeping the lock-out relay trip coil energized. In the old days, there were individual electro-mechanical relays which had "flags" which would indicate if a relay had actuated. Newer generator protection systems use ditigal multi-function relays which can replace 20 or 30 electromechanical relays--but there is usually some kind of display or interface (even if it's individual LEDs) that indicate what relay function is active.

But, from the information provided it's completely unclear if this is, in fact, an excitation-related trip or some other function (over-frequency; negative phase sequence; current or voltage imbalance; ground fault relay; transformer protection relay; etc.). How do you know for certain the trip was caused by the excitation system? What does the alarm text message on the GE operator interface display say?

There should be a set of electrical schematics (GE calls them "elementaries") that details all of the functions that can cause a lock-out relay to trip. If it's the result of a new-fangled digital multi-function relay you're still going to have to find out what function in that digital multi-function relay has not been reset, and why it can't be reset. Sometimes it's because of a blow fuse in a PT (Potential (Voltage) Transformer) that won't provide the proper voltage signals to the multi-function relay.

But we simply don't have enough information to be of any further help. We would need to know the age of the machine, the type of turbine control system, the type of excitation system, and it would be MOST helpful if we could see the SLD (Single-Line Diagram) for the machine. (.pdf, .png and .jpg files can all be attached to posts on Control.com, as well as text files and photographs). It would be MOST helpful, also, to know, SPECIFICALLY which lock-out relay is unable to be reset.

Be aware that I have seen repeated attempts to manually hold a lock-out relay in the RESET position have caused the coil to burn out, releasing smoke from the coil (and it's ALWAYS best to keep coil smoke IN the coil and not let it out, because once it's out it's not going to work properly again).

 

Dear all, I work with GT frame 9E GE. We are having trouble resetting the "excitation trip" alarm and this situation does not allow us to synchronize. We have already tried to reset with the lockout relay on the protection panel and excitation panel, without success, it seems that the trip coil still remains energized. Are we doing it wrong? Is there another way to de-energize the trip coil so that we can reset it without causing damage to the equipment? We are a new O&M team and have never had the same experience, it is difficult to solve this problem.

Hi

What are the AVR and Protection.. OEM.

 

Dear all, I work with GT frame 9E GE. We are having trouble resetting the "excitation trip" alarm and this situation does not allow us to synchronize. We have already tried to reset with the lockout relay on the protection panel and excitation panel, without success, it seems that the trip coil still remains energized. Are we doing it wrong? Is there another way to de-energize the trip coil so that we can reset it without causing damage to the equipment? We are a new O&M team and have never had the same experience, it is difficult to solve this problem.

Hello,
If you have EX2100 you should have a code for the fault and abrief on the excitation screen
you read the fault and try to find the reason for the trip