We found a "working" motor generator in the factory... 2

[jimbofitz]

One of our guys found a 5 kva 480V/60Hz to 115V/400Hz generator in a loft and decided to energize it after at least 15 years. To our amazement it fired up and supplied voltage on the output. The motor is a Delco model B-612A, 7.5HP. The generator is a Bogue Electric Mfg. Co. Model 2082.


However, it looks like the regulator is going to fail after a few hours of vibration due to corrosion/aging of the components and wiring. We are curious if it is possible to retrofit or repair the regulator to use for a test set.

Are any of you motor guru's familiar with a GE generator voltage regulator type BGA 20C? I have attached a photo for reference.

I'm not very familiar with motor/generator sets but if there is a reasonable solution to upgrading the regulator we would love to bring it back to life.

Any help is appreciated.

Thank you in advance for your comments.

Regards,
Jim

 

[jimbofitz]

Additional Photo's

http://files.engineering.com/getfil...970e-4408-882c-c2d4f72bf22f&file=IMG_0030.jpg

http://files.engineering.com/getfil...de05-4da1-82a3-4f0ea94f6919&file=IMG_0026.jpg

http://files.engineering.com/getfil...35fd-4d73-b116-635de0f8d001&file=IMG_0027.jpg

 

[dpc]

I'd check with Basler. They retrofit all types of old VRs.

David Castor

http://www.cvoes.com

 

[waross]

Many AYRs want to see a minimum field resistance. 16 ohms was a common figure from memory. That is the field fed from the AVR, not the main DC field on an exciter equipped generator. generator.
Check your field resistance and select an AVR that will drive it. AVRs are pretty interchangeable over quite a wide range on small gen-sets.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[itsmoked]

Carefully cleaned off I can see that regulator running a longgggg time.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[rasevskii]

Nothing wrong with that regulator. It works by stepping in or out resistance elements located behind the nameplate. See the reeds that are moved in or out of contact by the voltage sensing coil. There is an air dashpot to stabilize the action. The ohmite pot on the front is the voltage setting.
As ItSmoked said a careful cleanup and it will be well. Do not use WD40 on the moving contacts as that will leave a residue. Use some other solvent,like white gas, carefully...

Good luck with it.

rasevskii

 

[jimbofitz]

My main concern is that we will damage the regulator while replacing wires and resistive elements. The insulation is all cracked and some of the wires are even fraying. I don't even want to touch the reed switches.

It sounds like it would be wise to clean everything up and stick with the vintage equipment. I will let them have fun down back checking it out.

Rasevskii:

Is the Ohmite rheostat installed below the regulator part of the "standard" regulator or is that an aftermarket "improvement" for voltage control courtesy of our Engineering test department? I assumed the latter.

One last question that might get some interesting comments:
Will the regulator play along if we attempt to run this at variable speed? Right now it can only be used as our 418.5Hz generator but we would like to see if we can vary the range to test a wild frequency power converter in down the road.

Thank you all for having a look at this. I'll let you know how it behaves after a good cleaning.


Regards,
Jim

 

[rasevskii]

Well.if this is for commercial use in a production environment, rather than a hobby application, then you had better replace it with something more modern. Probably it dates from late 1940s to early 1950s, likely WWII vintage. If the wiring is that bad, then you cannot rely on it. The pot on front was likely standard. Also the slider type resistors can have bad contact at the slider if there is corrosion.

Relocating the regulator off of the frame on which the MG set sits, would be a better option. It would be rather sensitive to vibration, and that arrangement must vibrate terribly...The wiring inside the generator must also be in bad shape and what about the brushes...

rasevskii

 

[oldfieldguy]

You probably found it covered with dinosaur droppings.

Old technology, meant to be maintained and repaired with what we'd consider rudimentary tools.

I'm with rasevskii, though, if this is to provide more than services as a museum piece, I'd be looking for upgrades. That's a lot of iron for 5 kVA of capacity.

old field guy

 

[jimbofitz]

I completely agree the regulator might not have much life in it.

If it only requires man-power and some resistors/wiring to be in working order we might have them in our stock room from vintage products (our company makes transformers as well as power supplies dating back to the 30's). I'm afraid the switches will be difficult to replace.

Thank you for your advice. We will not have much expectation of this MG set coming to life.



Oldfieldguy:

Even the dinosaur droppings were covered in a horrible film that stinks of fish oil... it took plenty of 333 cleaner and elbow grease to make the nameplates re-appear!


Anybody want it

Regards,
Jim

 

[oldfieldguy]

Jim--

I don't need 400 Hz for anything. Now, it it were 125 VDC to 120/240 AC 60 Hz, I'd gladly take it.

old field guy