Niehoff 28V 400A type 76761-N1601 Generator Complete Disassembly/Assembly Instructions

[Jake59]

Hello,

Looking for a complete disassembly and assembly instruction for NIEHOFF Generator of type 76761 ?

I am having difficulty removing the bearing cover on the pulley side as it seems to jam on the bearing or something?
Do I need to use a bearing puller to get this cover off?
Any helpfull advice welcome.

Also, what kind of generator are these? I can see a stator on both sides and a solid iron core with 6 peaks mounted on the anker, so how does this then generate power? I am not an electrical engineer, so a simple common langauge street smart reply would be most appreciated.

Thank you for all your help,
Jake

 

[Mogman]

A brushless alternator uses a fixed (non rotating) field and stator windings similar to how an induction AC motor works, the fixed field winding induces a magnetic field in the rotor which in turn induces output current in the stator windings, many use two stator windings one for the field and one for the output and others use one stator winding and an external "exciter" current, most of the automotive type use an external exciter current. the dual voltage Niehoff alternators use two stator windings to deliver 28 and 14V.
Can't speak directly to your alt. but unless it has a retaining snap ring behind the front pulley the rotor should slide out of the bearing that said it may be a tight fit, be careful not to damage the front plate

 

[Jake59]

A brushless alternator uses a fixed (non rotating) field and stator windings similar to how an induction AC motor works, the fixed field winding induces a magnetic field in the rotor which in turn induces output current in the stator windings, many use two stator windings one for the field and one for the output and others use one stator winding and an external "exciter" current, most of the automotive type use an external exciter current. the dual voltage Niehoff alternators use two stator windings to deliver 28 and 14V.
Can't speak directly to your alt. but unless it has a retaining snap ring behind the front pulley the rotor should slide out of the bearing that said it may be a tight fit, be careful not to damage the front plate

Hi Mogman,

Thank you for your clear reply, I think I understand now how it works.
This particular Niehoff generator has 2 stator windings and both output + and both - are bridged togeter on the outside of the housing. This gen delivers 28V 400A.

From what I can see inside, there are 2 stator winding sets, each delivering 28V and also there seems to be a set of fixed coils mounted in the middle of the gen and in a circular patteern with the rotor divided into 2 parts, one on each side of these circular coils halves. So I assume this circular coil set generate the magnetic field in the 2 rotors, which in turn, when rotating, generate AC in both stator windings?

Thank you so much for this very helpfull explanation.
I'll make some pics to add to this posting...

Jake

 

[juanprado]

Not sure if you had seen these documents on the N1601 and if they are helpful to you?

 

[Jake59]

Not sure if you had seen these documents on the N1601 and if they are helpful to you?

Hi Juanprado,

Thank you very much!! All and any information regarding this generator is usefull, so well received!!

Thanks,
Jake

 

[juanprado]

No problem and my prayers for your part of the world to stay safe.

 

[Mogman]

Hi Mogman,

Thank you for your clear reply, I think I understand now how it works.
This particular Niehoff generator has 2 stator windings and both output + and both - are bridged together on the outside of the housing. This gen delivers 28V 400A.

From what I can see inside, there are 2 stator winding sets, each delivering 28V and also there seems to be a set of fixed coils mounted in the middle of the gen and in a circular pattern with the rotor divided into 2 parts, one on each side of these circular coils halves. So I assume this circular coil set generate the magnetic field in the 2 rotors, which in turn, when rotating, generate AC in both stator windings?

Thank you so much for this very helpful explanation.
I'll make some pics to add to this posting...

Jake

I think you have it figured out, two sets of stator windings to double the current, I suppose if one set failed you would still have some output

 

[Jake59]

No problem and my prayers for your part of the world to stay safe.

Hey Juanprado,

Thank you for that kind remark and concern!!

Jake

 

[Jake59]

Hi again,

Got the generator open and the rotor separated. What an interesting design and assembly.
The rotor halves actually attach with 6 small screws onto the axle.
Just need to press the pulley sice cover off of the axle and then I am ready...
Pictures to follow.

Thanks for all the help and advice!!

Jake

 

[Jake59]

Hi again,

Got the generator open and the rotor separated. What an interesting design and assembly.
The rotor halves actually attache with 6 small screws onto the axle.

 

[TOBASH]

Remind me WHY you’re doing this?

Cool to see inside, but what’s the purpose of this exercise?

 

[Mogman]

Maybe a bad bearing? looks like the front rotor may be getting a little close to the windings.

 

[Jake59]

Remind me WHY you’re doing this?

Cool to see inside, but what’s the purpose of this exercise?

That's a very valid question! This is a brand new unused generator.
But I'll have to ow you an answer for now, it's too early to reply yet... no damage is being done, other than discovering, learning, understanding and a little experiment.
And if the outcome is unsatisfactory, the entire system will be re-assembled and put to use as is...

Jake

 

[Action]

That's a very valid question! This is a brand new unused generator.
But I'll have to ow you an answer for now, it's too early to reply yet... no damage is being done, other than discovering, learning, understanding and a little experiment.
And if the outcome is unsatisfactory, the entire system will be re-assembled and put to use as is...

Jake

But there are always pieces left over when we put things back together !