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Discussion Starter #1
I have a Generac 5,000 watt, that each time I run it, I have to keep filed flashing it, to getit to generate. Is their anything I can do to get the magents to keep their magnitism. I tried running under a load for an 1/2 hour, but that didn't help.
 

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Post of interest, not sure how to make the field flashing permenant:

http://www.perr.com/tip16.html

Field Flashing of Portable Generators

This tip comes from the Briggs & Stratton Customer Education Department. As an alternative to flashing a rotor winding with a battery applied to the brushes, an electric drill may be used. Follow these steps to flash the generator:
• Plug the electric drill into the generator receptacle. (Cordless drills do not work)

• If the drill is reversible, move the direction switch to the forward position.

• Start the generator

• While depressing the trigger on the drill, spin the drill chuck in reverse direction. This will excite the field and the generator will now produce electricity. If spinning the chuck one direction does not work, try spinning the chuck in the other direction as you may have the reverse switch positioned backwards.
Use caution not to get your hand or other materials caught in the chuck. As soon as the field is excited, the generator will produce power and the drill will turn on.
The reason this works is because the electric motor in the drill will act as a small generator when spun backwards. The magnets in the drill's motor induce a voltage into the motor windings, which is fed back through the trigger, cord and into the generators receptacle. From there it goes into the power winding of the stator. The voltage going through the power winding creates a magnetic field, which is intensified due to the iron core of the stator laminations. The rotor intersects this magnetic field as it is spun past the power winding, thus inducing a voltage in the rotor winding. Once current flow is present in the rotor winding the rotor has been flashed.
If flashing the field does not make the generator work, you may have additional problems, besides a lack of magnetism in the rotor. Further testing will be needed. Hopefully, this will give a simple way to field flash your generator if needed -
 

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Discussion Starter #3
I had to keep doing that drill method to get it to generate. I gave up and sold the generator. I assumed that the magnets where shot, and probably needed replacement.
 

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Looked through the Generac site, not much help unless you have the Ser/Mod#. Was thinking there had to be a circuit that flashed the gen head upon start up?? Without a schematic there's no telling. Read that the magnets on some were suppose to retain enough charge to reexcite the magnets when started. To bad it wouldn't work for you, sometimes it's best to move on and buy a better unit. Had an old Honda gen (a gift horse :) ) doing the same thing, still have the motor but never could get the gen head to work right, come to find out it had been in a flood so no wonder! Nothing is worse than fighting an old generator in the dark trying to get it to work one more time when you really need it!

Best to you! :fing32:
 

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CalifornianGravelynator
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what rpms is the engine running?
 

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Discussion Starter #6
I set the rpm's to 3,600, and it would put out the correct hz, It was at 62hz. This is the second generator, same model, I bought that had magnet issues. But that one stayed working, after I did the drill field flashing. I thik this model isprone to this issue. I buy them to flip. They usually have carb issues, from being stored with gas in the carb's.
 
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