S
We have 4 nos GE 6B GT. 2 of them are having "COMBUSTION TROUBLE" for last 6 months. All are having DLN system and all are 10 yrs old.
When the machine deloads from base (say 33 to 35 MW) at 30 to 29.5 MW, the machine jumps to 22 to 24 MW generating the following alarm "COMBUSTION TROUBLE". Then it comes back to 30 to 29 MW immediately and finally it goes to required preselected load.
We checked all exhaust thermocouples and found okay. We calibrated all gas valves (SRV, GCV and GSV) and found "Incorrect null bias servo current" message for GSV only!! But valve movement is fine and physical position is same with the required value.
What else should be checked to solve the above problem?
When the machine deloads from base (say 33 to 35 MW) at 30 to 29.5 MW, the machine jumps to 22 to 24 MW generating the following alarm "COMBUSTION TROUBLE". Then it comes back to 30 to 29 MW immediately and finally it goes to required preselected load.
We checked all exhaust thermocouples and found okay. We calibrated all gas valves (SRV, GCV and GSV) and found "Incorrect null bias servo current" message for GSV only!! But valve movement is fine and physical position is same with the required value.
What else should be checked to solve the above problem?