Info: GE frame 9e, Dual fuel operation. Rated 110MW.
After completion of Combustion inspection, as normal practice we start up the unit on fuel oil, changeover test and test on start on gas operation. Initially, there were attempt 2 starts on fuel oil. Both failed with alarm only failure to ignite. Then the unit started on fuel gas, and it was all working fine, until FSNL and managed to changeover from fuel gas to fuel oil and back to gas. Then, they attempt to start again 2 times to start on fuel oil, same thing happened. Failure to ignite.
Nothing was one, out unit declared to operate only on fuel gas. The one day, the unit was requested to run up to base load operation. Somehow the GT behaves strangely the spread on the exhaust thermocouple is higher on the lower side, shown by TTXD 5 to 8. The spread 1,2,3 become higher and it is very near to the allowable spread limit. The unit could not reach base load, because it tripped at 100MW due to Exhaust temp spread high trip.
Can someone kindly helps to explain this issue?
After completion of Combustion inspection, as normal practice we start up the unit on fuel oil, changeover test and test on start on gas operation. Initially, there were attempt 2 starts on fuel oil. Both failed with alarm only failure to ignite. Then the unit started on fuel gas, and it was all working fine, until FSNL and managed to changeover from fuel gas to fuel oil and back to gas. Then, they attempt to start again 2 times to start on fuel oil, same thing happened. Failure to ignite.
Nothing was one, out unit declared to operate only on fuel gas. The one day, the unit was requested to run up to base load operation. Somehow the GT behaves strangely the spread on the exhaust thermocouple is higher on the lower side, shown by TTXD 5 to 8. The spread 1,2,3 become higher and it is very near to the allowable spread limit. The unit could not reach base load, because it tripped at 100MW due to Exhaust temp spread high trip.
Can someone kindly helps to explain this issue?