dear all,

I have problem with vibration, our system is SteamTurbine(5500RPM)-Gearbox(output 1500RPM)-Generator-Exciter-Permanent Magnetic Generator(PMG)

Problem: High axial vibration at PMG. with spectrum dominant at 5500, please have a look at file attached.

1. PMG itself rotate at 1500 RPM.
2. PMG frequency is 50 hz so electrical problem due to air gap stator and rotor should be dominant at 6000RPM.

is there somebody could help me?

What type of bearings? If anti-friction bearings, do you have part number? Do you have number of gear teeth? Can you provide the frequencies of the other peaks in the neighborhood?