procedure for flashing 1-phase generator

[damengr]

I am new to this forum. I am an Agr engineer who still gets his hands dirty daily. I have an old Forney PTO driven generator that appears to be good. Not shorted, Etc..

I can only get 8 volts output. It is a 2 pole single phase brush type with a capacitor. It has been sitting for a long time. I assume that the fields need to be flashed. I have three wires attached to brushes on each side of the slip rings. However there are no markings for F+ or F- to determine where the flash curent should go. I tried a 12 volt across 2 wires on the same side of and could cause the rotor to turn 90 degrees. After this I would generate 8 volts.....

Can someone describe or point me to the procedure. This is not worth taking it to a service shop... And I know I can do this. My field is Agr Engineering Power & Machinery.


Thanks

Damengr

 

[corrosivo]

If this is a AC generator as it appears (2 pole)and it have 8 volts (ac?)on the terminals you already have some remanent magnetization on the field this can be used to buildup the field voltage.
You need an exciter for rectifing/regulating the field voltage.
But before you do anything you better check the insulation condition of the machine, you say that was sitting for a long time probably the insulation is dirty and with humidity, so a cleaning and revarnishing is in order if you don't do this maintenance you will burn the machine, replace the bearings too. Maybe you will have to go to the service shop after all unless you know some generator excitation theory.