Gas turbine tripped with "LONG DC RUN TIME"

[reza1977]

Hi every body,
the GT10B2(SGT600) Gas turbine's rectifier 440 vdc has been failed due to high temp. Of inside and then Gas turbine tripped due to a "LONG DC RUN TIME" alarm despite of the presence of gas turbine's AC power. In this situation, lub oil pumps are working with batteries for 10 minutes and they are not working with AC power! Lubrication pumps have both AC and DC supply and they are working with own SFC's ABB ACS800.
Could you pls advise me why this trip alarm was issued despite of presence of gas turbine's AC power supply?

 

[goutam_freelance]

Check if there is problem with AC lube oil pumps or power supply to the same.

 

[reza1977]

Hi, In SGT600 gas turbines, there are no separate AC and DC lubrication pumps, instead the pumps have AC and DC feeds. AC feeds and it's loop were faultless.