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TERMINE und FORUMSTECHNIK => International discussion forum in english language => Thema gestartet von: Beemerdoc am 13 Januar 2022, 15:23:07

Titel: R26 6 volt Generator Help
Beitrag von: Beemerdoc am 13 Januar 2022, 15:23:07
Hello, everyone.
I am helping a good friend trying to restore a generator for a 1957 R26, and have a few questions

After taking it apart, it is obvious to me that the project was doomed from the beginning. Someone told him to cap off the two wires in the field that appear in the pictures.
One end of the loop went to the field terminal on the regulator, but the other end was capped off, so there is no circuit completion. The fields and armature are new, and he had installed a new electronic regulator in place of the original (also pictured). There is a second wire capped off, that I also have no idea where it goes. This original regulator looks to be in fine shape, so I would like to use it, if it is functional.

So, if you folk would be so kind to advise me, I would greatly appreciate it.

There is a small wire from the positive armature brush to terminal 61 on the bridge plate. Is that also where the other end of the field coils go? I do know that the charging light also goes here, according to the wiring diagram. And, what of that small wire that is capped off on the other end of the fields? Does it need to be somewhere, and if so, where?

Thank you all in advance for your wisdom in where I proceed.

Thomas
Titel: Re: R26 6 volt Generator Help
Beitrag von: kahlo am 14 Januar 2022, 22:08:20
Hi Thomas,

quite difficult to help here... was that really necessary to take out the coils?

With reference to your first picture: The lower end goes to D+ and 61. The upper white end goes to DF+. The additional wire on this coil should go via a resistor to Ground (probably not necessary if you use an electronic regulator, see instructions). No guarantee ;-).

Good luck,
Kahlo.
Titel: Re: R26 6 volt Generator Help
Beitrag von: Hansdampf am 14 Januar 2022, 23:24:10
The brushes are wrong connected. The both wires must be crossed.
Titel: Re: R26 6 volt Generator Help
Beitrag von: Hans Otté am 15 Januar 2022, 12:36:10
Hi Beemerdoc,

Your questions on the matter shows me you are not an expert to the challenge you are actually to be solved.

As shown by the pics the whole generator is already dismounted and now it needs quite a lot of knowledge on the matter to make it work again as it should do.
If you are not really an expert with a lot of experience and know-how, i rather would advice you to address to our professional guy here at the board named "Hansdampf". He may perhaps give you a helping hand to rebuild the generator correctly to a technical good working condition. You better talk to him what to do now to get off your problem. Even it may first seem easy to you to fix and adjust the dismounted coils into the generator housing with the proper and safe gap to the rotor it requires, some experience to do this in a professional way and to avoid later-on damage to the mechanical parts and the whole electrical system (wiring and adjustments) is still necessary. Take a good decision, kind regards, ******
Titel: Re: R26 6 volt Generator Help
Beitrag von: Beemerdoc am 15 Januar 2022, 16:32:38
Thank you all so much for your replies.
As for the reason for removing the field coils, we needed to start from the beginning to ensure this would corrected to actually work.

I found a picture on the site here that showed the correct positioning of the field coils, and orientated them accordingly.
Using a couple of precision tools that I had for another use, I installed them so that they were in proper alignment so as to have the arc of the shoes match the curvature of the armature. After securing and aligning, I used 4 feeler gauges to determine that I wound up with an air gap of about .009 inches(.229mm).

As for the various connections, I noticed that there was an internal connection between "A" on my picture to terminal. I soldered my D+ from the fields to that terminal, and put the other end of the fields to the "F" terminal of the electronic regulator. I put the other 2 wires of the regulator to Terminal "51" for the red as it is bridged to terminal "30", and terminal "61" for the blue. The brown went to ground of the generator. I know that there is a blue wire coming from the charging light that also goes to "61", and a red wire going to "30".
I then crossed the brushes as mentioned. I used some liquid tape to insulate the bare brush wire, just to avoid anything going wrong in use.

It seems to me that this should now work as intended. I welcome any correction that may be necessary.

Kind regards,
Thomas
Titel: Re: R26 6 volt Generator Help
Beitrag von: Beemerdoc am 20 Januar 2022, 18:46:15
Well, I am happy to report that the machine lives!  The light went out slightly above idle, and it is charging 8.1 volts at around 2000 RPM.

Thank you all for this forum and the various suggestions.

Kind regards to all,
Thomas
Titel: Re: R26 6 volt Generator Help
Beitrag von: mekgyver am 20 Januar 2022, 19:05:36
Hi Thomas, nice to read about your success, congrats !  :blumen:
But now the field-regulator needs to be adjusted to 7,0...7,1V, measured at the battery-poles.
You have strongly to watch, that the voltage limits under 7,2V, because the hydrogen will gasing out to this value, that has to be avoid.

If this electronic regulator don´t have an adjustment-sqrew, you can use the R27 electric-mechanic-regulator. An adjustment here is a work for a specialist, but find out in the literature, there will be instructions about that stuff.

Good luck, mek  :schrauber:  :prost: