D
Hi,
On a GE design Frame 6B gas turbine, ~40MW, built by European Gas Turbines, during stator testing we disconnected the neutral earthing resistor on the generator star point and the generator phase winding tails. We were trying to find out what the resistance of the neutral earthing resistor should be - we found it to be open circuit - maybe a damaged resistor. Also after opening the flexibles between the MV frame and the generator circuit breaker (which had the earth switch closed) we found an earth path from the busbars in the MV frame to earth (for DC) possibly through the voltage measurement devices, is this normal? What type of devices are these that pass DC but provide high impedance to AC? Thanks.
Regards,
David
On a GE design Frame 6B gas turbine, ~40MW, built by European Gas Turbines, during stator testing we disconnected the neutral earthing resistor on the generator star point and the generator phase winding tails. We were trying to find out what the resistance of the neutral earthing resistor should be - we found it to be open circuit - maybe a damaged resistor. Also after opening the flexibles between the MV frame and the generator circuit breaker (which had the earth switch closed) we found an earth path from the busbars in the MV frame to earth (for DC) possibly through the voltage measurement devices, is this normal? What type of devices are these that pass DC but provide high impedance to AC? Thanks.
Regards,
David
