A
I work in GE Frame 9 Gas turbines of which control system is Mark IV. One of GT 2 (two) times trip due to No-3 Bearing Metal Thermocouple reading high.
No-3 Bearing has 2 thermocouples (Ungrounded): one BTJ31 & other is BTJ32. Though both are 2 elements thermocouples but only one element connected in the Mark IV. Problem is with BTJ32. It is sometimes going to high value and But BTJ31 is showing normal value. So when first time GT tripped we replaced BTJ32 Thermcouple and cables. But GT again tripped as it jumped to trip value but that time BTJ31 was showing normal value.
Could anyone explain me why it is happening as we know thermocouple if it is became defective than it goes to low value? and how to solve this problem? It will be a great help for me & it is urgent.
No-3 Bearing has 2 thermocouples (Ungrounded): one BTJ31 & other is BTJ32. Though both are 2 elements thermocouples but only one element connected in the Mark IV. Problem is with BTJ32. It is sometimes going to high value and But BTJ31 is showing normal value. So when first time GT tripped we replaced BTJ32 Thermcouple and cables. But GT again tripped as it jumped to trip value but that time BTJ31 was showing normal value.
Could anyone explain me why it is happening as we know thermocouple if it is became defective than it goes to low value? and how to solve this problem? It will be a great help for me & it is urgent.