2 Brush Generator Rotation Direction

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RedPanEd
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2 Brush Generator Rotation Direction

#1

Post by RedPanEd »

I have two spare 2 brush 12 volt generators that I wanted to test to see if they would work.
I started by "motoring" them by hooking up a charged spare battery positive to the "A" terminal, connecting the "f" terminal to the generator case , and connecting the battery negative to the generator case.
Both generators motored, but one went clockwise and the other counter-clockwise!
I search the knowledge base, but could not find the answers to these questions :
Question 1, Which direction should the generator motor (clockwise or counter-clockwise facing the generator output shaft)?
Question 2. To change rotation direction do I swap the field coil wires between the armature stud and the field stud? If not, how?
Question 3. What is the rotation direction of the generator when installed on the bike with the motor running?
Thanks for your help with these questions!
RedPanEd
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Re: 2 Brush Generator Rotation Direction

#2

Post by nmaineron »

Your genny spins Counter clockwise.
RedPanEd
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Re: 2 Brush Generator Rotation Direction

#3

Post by RedPanEd »

Facing the output shaft, installed with the engine running?
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Re: 2 Brush Generator Rotation Direction

#4

Post by RUBONE »

Scroll down on the link until you see the timing gears, then look at them to determine why it rotates CCW.

Pinion gear rotates CW
Timer drive rotates CCW
Idler gear rotates CW
Therefore generator drive gear, and consequently generator drive shaft, rotates CCW

Engine - Gearcase 1955 - 1957
RedPanEd
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Re: 2 Brush Generator Rotation Direction

#5

Post by RedPanEd »

Thanks RUBONE for answering question 2. How about question 1 & 2?
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Re: 2 Brush Generator Rotation Direction

#6

Post by RUBONE »

1, it depends on the position of the armature when power is applied.
2, No, don't change the leads, follow the factory wiring. (it is all in the service manual).
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Re: 2 Brush Generator Rotation Direction

#7

Post by panheadrider1961 »

did you polarize before testing ? that may be ccw reason if been sitting idle lost its magnetic field
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Re: 2 Brush Generator Rotation Direction

#8

Post by RooDog »

Hey Fellas.....
I have not motored a generator in many years, but I am wondering here if one were to reverse the polarity of the 12V power source, hot battery, swapping the + and - leads, would that change the rotation when motoring.... I have always grounded the Field terminal to the case and attached the Neg lead there, Pos to the Armature terminal......
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Re: 2 Brush Generator Rotation Direction

#9

Post by Andygears »

As Rubone stated, it probably matters where it is when energized. And... It's not a motor after all! And..... Does it really matter? Won't a generator put the same output whether it rotates CW or CCW? Questions that might not need answers.

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Re: 2 Brush Generator Rotation Direction

#10

Post by cant-drive-55 »

The pole shoe retains a small amount of magnetism. This provides enough field for the generator to start and then energize the field. That's why you should polarize the gen after disconnecting the charging circuit or if the gen has been sitting for a while.

The 'reverse' spinning gen probably began turning the direction the armature position favored.
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