How to resolve exhaust spread trip issue in Frame 5 MArk VIe GAs turbine?

[cni2ltps]

Dear Sir,

We have a frame 5 GT of BHEL of Capacity 20 MW and the control system was upgraded from Mark IV to MArk VIe.The exhaust spread trip was not there earlier and the trip was incorporated after the upgradation. The problem detected was that the allowable spread becomes lower than the real spread which trips the unit.The exhaust thermocouples were inspected and found to be healthy and all the fuel nozzles were cleaned.The real spread is found to be around 40 C and the adjacent spread is around 15 C.The parameters that determine the allowable spread are the compressor discharge temperatures,average exhaust temperatures,some real time offsets and constants.Kindly guide me through to resolve the issue.

Regards
C&I
LTPS

 

[Hoxton]

I suggest that you red flag this post and repost in "Engine and Turbine Engineering. Turbine engineers may not be monitoring the forum you posted in. Good luck!