Machine Info:
Gas Turbine: GE 9FA,Mark VIe control
Cause of Shut down/Trip:
ST> Tripped due Auxiliary Power failure because of Voltage fluctuation from Grid side.
Before Unit Trip:
Single/Combined cycle:Combine Cycle
Reason for Trip:
Problem during GT Trip:
Due to Grid voltage fluctuation, damper signal loss power and Limit switch sensor troubleshoot fault alarm come and thus GT trip due to Damper limit get no feedback then GT trip
Sequence of Trip
From 6.6KV Load A Incoming Breaker A 10BFAA01 TRIP >>
ST MAIN LUBE OIL A&B TRIP >>
DC Operating Lube Oil pump operate >>
ST Low Lube Oil Pressure Come >>
ST Trip>>
10BFA07 Coupler delayed to operate>>
Damper Associated Breaker from 6.6KV Load B bus bar 10BMCO2 Trip>>
In the workstation GT alarm found in Mark VIe
Damper Limit switch troubleshoot fault alarm come >>
Damper Feedback Signal Loss >>
GT Trip
Analysis:
Due to Grid Voltage fluctuation Turbine Hall 10BFA01 Incoming Breaker tripped:
This is the incoming breaker 10BFA01 of Bus-A fed from 6.6KV Load A and transform to ~415 V>> breaker 10BFA01 , this incoming breaker remained de-energized because of the faulty Under Voltage relay or ABB multi functional 3 phase RMS monitoring relay
Gas Turbine: GE 9FA,Mark VIe control
Cause of Shut down/Trip:
ST> Tripped due Auxiliary Power failure because of Voltage fluctuation from Grid side.
Before Unit Trip:
Single/Combined cycle:Combine Cycle
Reason for Trip:
Problem during GT Trip:
Due to Grid voltage fluctuation, damper signal loss power and Limit switch sensor troubleshoot fault alarm come and thus GT trip due to Damper limit get no feedback then GT trip
Sequence of Trip
From 6.6KV Load A Incoming Breaker A 10BFAA01 TRIP >>
ST MAIN LUBE OIL A&B TRIP >>
DC Operating Lube Oil pump operate >>
ST Low Lube Oil Pressure Come >>
ST Trip>>
10BFA07 Coupler delayed to operate>>
Damper Associated Breaker from 6.6KV Load B bus bar 10BMCO2 Trip>>
In the workstation GT alarm found in Mark VIe
Damper Limit switch troubleshoot fault alarm come >>
Damper Feedback Signal Loss >>
GT Trip
Analysis:
Due to Grid Voltage fluctuation Turbine Hall 10BFA01 Incoming Breaker tripped:
This is the incoming breaker 10BFA01 of Bus-A fed from 6.6KV Load A and transform to ~415 V>> breaker 10BFA01 , this incoming breaker remained de-energized because of the faulty Under Voltage relay or ABB multi functional 3 phase RMS monitoring relay