Any generator gurus in the house?

I am the current custodian of a set of twin Bolinders Diesel/Anton Piller generating sets from around 1966-68. They used to be part of the UPS system for one of the substations of the DECCA Navigators Skagerak-chain of radio beacons, and as such had the controls integrated in the main cabinets of the installation. Which unfortunately did not survive the cleanout of the building in which they were installed. They were the emergency back up for Violet Slave Årjäng in Sweden, to be precise.

They are the best preserved engines I ever saw. They sat for 55 years in the same heated facility, meticulously maintained. One has 560 and the other 580 hours on the meter, and they start and run like new engines. I got them only last summer, with clear engine oil, fresh radiator fluid, clean airfilters, and almost like they came from the factory only last month. The dieselpumps are still covered in their factory wax coating, and pristine and shiny under it.

Here's a pic from the sales ad in their installed location:



Only flaw I can find with them is that one of the generators regulate the output at a somewhat higher voltage than nominal, 250V instead of 230V. Probably due to a dried up capacitor or something in the 55 year old regulator. They also came with a couple of sturdy ASEA 3 phase transformers to 400V of the same vintage, but as indicated without control/instrument cabinets.

I intend to build new control cabinets and dieseltanks for them, preserve them, and keep them in my collection until I get an offer I can’t refuse. Or until I get old enough to find out that it’s time to downsize. They’re a joy in that state, plain and simple. Museum quality items.

My problem is that I only have a crude understanding of the workings of the generators. And I would like to equip the self-regulating, rotating armature/slip-ring voltage delivery 35 kVA Anton Piller NSYK-4-723 units with modern external regulators. To replace the old internal circuits, which are located above the slip-rings and commutators. So I need some help in understanding the exciter system a little better, and hopefully in finding suitable modern replacements for the exciter control.

They both work, so I'm in no particular hurry with it, but if someone could give me a few pointers regarding some issues and questions I have, I would be delighted for the assistance in better preserving these fantastic pieces of equipment.

Even though they have a rotating armature and a static exciter winding, they're in principle and schematics constructed pretty much exactly as the more common configuration with a fixed armature. My problem lies in classifying and understanding the exciter system better, figuring out how and where to regulate it, and chose a suitable regulator.

The pictures above somehow got trimmed down in the post, click them for a full view of the commutator next to the sliprings.

norseman wrote:The pictures above somehow got trimmed down in the post, click them for a full view of the commutator next to the sliprings.

Unfortunately the trimming occurs because modern digital devices take such large pictures but, as you say, clicking on the image will take you to servimg where all is revealed. There is an option to resize as you host.

Have you tried contacting ABB? they were ASEA before amalgamating with Brown Boveri in the late 80's https://global.abb/group/en
Point out you are preserving some of their history and they may be able to supply information of the original installation from their archives.

Woodsman wrote:

norseman wrote:The pictures above somehow got trimmed down in the post, click them for a full view of the commutator next to the sliprings.

Unfortunately the trimming occurs because modern digital devices take such large pictures but, as you say, clicking on the image will take you to servimg where all is revealed. There is an option to resize as you host.

Thank you. I'll look into it and see if I can figure it out the next time I have a picture to post.

Robotstar5 wrote:Have you tried contacting ABB? they were ASEA before amalgamating with Brown Boveri in the late 80's  https://global.abb/group/en
Point out you are preserving some of their history and they may be able to supply information of the original installation from their archives.

Oh I have tried that. The genny itself is an Anton Piller unit from Austria, and the company is still in operation. I emailed both the main office in Austria and their norwegian subsidiary, and all I got was crickets.

Unfortunately we live in a corporate world, where profits and the upcoming bottom line is everything that matters. They have most likely done the same as for instance Volvo/Volvo BM/Bolinders Diesel did. Which used to keep an extensive online archive of their history, development, engines and machinery. 3-4 years back everything got scrubbed. It most likely generated questions and requests, so the choice was to remove it, and simply ghost the people who where giving them enquiries about their vintage stuff. It was a huge archive, including pdf's with technical detalis, pictures, drawings, news articles from the time, you name it. Poof gone.

So in short, yes, I tried that, to no avail.

But thank you for the suggestion. A few years back it would probably have worked, but not anymore.

I have also sent a request for some assistance in choosing a replacement regulator to a couple of the aftermarket suppliers and service shops. Together with a simple but accurate selfmade pdf drawing of the circuitry. But even they won't touch it, they probably get intimidated by the age of it and the rotating armature.

The old school craftsmen that had an intimate knowledge of how their machines worked are unfortunately dying out. Now they need electronic diagnostic tools, factory support, and a screen that tells them what to do before they at best dare change out some component.

As said, I have a crude understanding of it, and the excitation resistance and current are given on the label. I would nevertheless be delighted with some feedback and reassurance from an expert in the field. Both regarding classifying the type of excitation, of which there are many, and in choosing a relatively simple and sturdy and efficient regulator for them.

Can the forum support hosting a pdf drawing btw?

I found an image converter. The notes are obviously in norwegian, but from the armature slipring u-v-w input to the inbuilt regulator in the top left, the commutator, junction box and field windings can be discerned. Sorry for the quality of the drawing, but to the best of my knowledge it is electrically correct. A rather simple circuitry really, but I still ruminate over a few issues.