PMG Pole cap Fasteners were tighten less than 20 Nm whereas it should be between 35-37 Nm. But still there is no crack on Pole cap but magnet under the pole cap are damaged.
It was balanced three phase load and started with 3 Generators. Other two Generators did handle the load very well. It has nothing to do with the load I guess but I can't see any reason of damaging magnets. All electrical and magnetic tests were fine.
It was balanced three phase load and started with 3 Generators. Other two Generators did handle the load very well. And it's not external excitation system. There is a exciter system within the generator. You are right, it has nothing to do with the load I guess but I can't see any reason of...
Generator - 1800rpm, 11kV, 656A. While running Gen, a large load was turned on, and excitation voltage went from 23V to 120V, but that's a normal situation that happens every time and on all Generators. But this time after turning on the large load, vibrations started increasing, and Gen tripped...