We have GE frame 9E gas turbine. We have a carbon brush at Brg#4 i.e Generator DE. I want to know how the electrostatic charges developed in compressor are grounded. Is there any carbon brush near bearing no#1.

Recently during inspection one of the accessory gear box of a GT, half bearings of main shaft of the AGB was observed pitting marks, indication of leakage current.

Could anyone explain??

Regards
BSJhala

 

Similar Problem was noticed in Frame6 GE machine, we had observed sparking in Accessory gear box near Brg No1. The problem had started after long time, we had identified the problem to be from Magnetic clutch assembly (For Liquid fuel pump. The Magnetic clutch was ok, but earthing observed in one core of the Electrical connection. we had then removed the connection. Now, it is ok, Still kept under observation.

regards
VBS