Exhaust thermocouple failure on GE Frame 9 Mark V gas turbine

[transporter84]

hi everyone:
i have a question about gas turbines :

i am working as instrumentation engineer( beggar ) at a power station .. we use gas turbine GE ( mark V) frame 9 .

i got that alarm : exhaust thermocouple # 10 fail , drop number 123

if anybody working in such a field can help me in analysis & solving that problem i will really approtiate that .


thank u so much

 

[Astronuc]

I'm not sure anyone here (at the moment) is using the technology.

Here is the page for GE tech manuals. http://gepower.com/online_tools/tech_manuals.htm

I would think that part of the turbine/plant purchase would include manuals with warning messages/alarms and the appropriate actions to be taken.

Why not contact GE technical support directly?

 

[stewartcs]

Maybe I'm pointing out the obvious but it seems to me that you have a failed thermocouple that needs to be replaced.

CS

 

[FredGarvin]

Can you be more specific about the alarm notification you received? Does that mean that you simply lost the TC, i.e. it is now open, or you are actually seeing high EGTs?

 

[transporter84]

thank u everyone who care , about the alarm .. i wrote it as i saw it exactly .. nomore .. no less

 

[Astronuc]

As stewartcs indicated, the thermocouple could have simply failed, in which case it needs to be replaced. I'm not familiar with that T/C or Frame 9 turbine, but if it's hot (exhaust) this presumably would require that the unit be shutdown.

Is the thermocouple in the a well? Could the well have been breached (ostensibly due to erosion/corrosion)? Has the T/C reached it's lifetime or the min expected lifetime? Are there redundant T/C's?

 

[jaap de vries]

Definitely contact GE they should be able to help you immediately. At least that is how it works at Rolls Royce with the industrial RB211 and Trend series. Also Astronuc makes a good point, maybe direct replacement is not an necessity usually there are two or three exhaust thermocouples and there should be standard protocol if it should be replaced immediately or not.

 

[lsspt]

Here is a picture from a GE gas turbine data analysis system, I hope it may help.
More pictures can be found at http://www.leiosoft.com/ana/screen_en_win.htm"

http://www.leiosoft.com/ana/win/eng/Snap4.png

 

[chayced]

From what I've seen thermocouples do fail but more often than not it is the wiring/connectors. Check the readings from any points you can between monitoring system and the actual thermocouple. Probably just a loose connector caused by constant vibrations.

Whatever it is you are going to need to go through troubleshooting to find it.

 

[FredGarvin]

Considering that this thread is just about 10 months old, I doubt the OP will be checking back.

 

[chayced]

Hmm, guess he solved the problem then :)