We have GE flame 6 B MKVI control. Last night we turned off power supply Core R controller for replacing UCVE card by unit still run at 22MW. No problem. But this morning unit Trip by L4T. We checked at a panel found alarm POWER SUPPLY R Controller fault (Lamp LED) and alarm event at HMI shows cooling air generator HH TRIP. (Slot 18 :VRTD is Rack 0 Chanel R (SIMPLEX))
I am confused. Why between OFF POWER SUPPLY vs power supply fault is there effect to unit trip and some RTD sensor shown value High?