Ab Drive Problem??

frieds
we are using AB drive model 1336F-B125-AA-EN in one of our desalination application to drive a high pressure pump.Power for this plant is provided independantly from a 230 KW generater .Due to faulty operation of generaters(voltage fluctuations) we faced problems in these drives and had to replace Gate driverboard and precharge board from a working Drive in another plant.All previously programmed values were not disturbed
Now,when the drive is started, it is working ok for sometime and all of a sudden the supply voltage is dropping from 405 Volts to 360 volts causing drive to trip.Just before tripping the measured values on the HIM are :
VFD OUTPUT CURRENT:145Amps
VFD OUTPUT VOLTAGE:243Volts
VFD OUTPUT POWER :50
DC BUSBAR VOLTAGE:510
OUTPUT FREQUENCY:29.3Hz

Could this problem be due to any fault in the Drive?
Can any one suggest me what could be wrong in the drive.
Generater is assumed to function alright.

This sounds like a generator problem. There is very little that the drive could do (other than overcurrent) to cause the supply voltage to drop like this.

Your data shows that overcurrent is not the problem so I would focus on the generator.

Why dont you investigate the fault code ? By checking the fault code with the operating instructions you can get a more concise explanation why the drive trips.
But dont be surprised if it says "caused by supply under voltage".

Thanks a lot Mr.Dick and Jesper
Luckily we had a third generater to check the plant.Now the drive is functioning ok without any voltage dropouts.Now its time to investigate the problems in faulty generaters...