Help Identifying Wind Turbine.

[Kevin Baluha]

I just bought this place and it has a broken wind turbine. To fix it I am trying to identify it. Here are some key features.

1. Aluminum Blades appear to have a 'feathering system' with counterweights for overspeed i guess.
2. It doesnt look like its direct drive.
3. There's no tail section but i think its supposed to have one. the generator is huge - about the size of 5hp ac motor.
4. theres a brake cable that runs to the base of the tower.

old owner says its a Parris Dunn 5kw but I don't think they used brakes or counterweights. he also said it's ancient but i think the aluminum blades would have been from the 70s.



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[Rob Beckers]

Kevin, welcome to the forum!

Would you have better pictures of the turbine that you can post? Something a bit closer-up would be good.

-RoB-

[Dave Lahar]

It looks like a Dunlite. They made a (massive) 2 kW with sheet metal blades, fly-ball governor and a tail that often failed with lack of maintenance.

[Kevin Baluha]

Dave I think you are right - Were the dunlite's any good - i would need to make/get blades, a tail, and go thru it. its awfully big for 2KW. should i just take down and put a new system up or fix it?

[Dave Lahar]

Yes and no. The generator, gearing and hub is heavily overbuilt, but the tail hinge was a bit of a weak spot as I recall. With routine maintenance they were pretty good overall. Really heavy to take down or put up; around 600# IIRC.

Where are you located? I have a friend that used to have quite a few parts, and even had built some wood replacement blades. I can check to see if he has anything still - and put you in touch if he's willing.

[Kevin Baluha]

I am in Colorado north west of boulder. would love to talk to anybody who's into wind/dunlite.

[Kevin Baluha]

i would have to make or find a tail - i cannot locate any part of it..

[Neil Hochstedler]

Hi- I'm Dave Lahar's friend. WE worked together at a company that sold and installed these things in the late '70s and early '80s.

Yes, it's a Dunlite, most likely a 2kW, 110VDC. You can verify by looking on the body of the alternator, on the top where it joins the gearbox. Voltage and rated power should be stamped there.

Your machine is a gearbox driven (5:1 ratio) brushless 3 phase alternator, quite a feat for its time. (Designed in the '50s.) Many diodes are required to make this all work, and two of the factory field diodes fail whenever there's lightning in the area. All easily fixable once they're located and identified.

All the bearings in the gearbox, alternator and hub are standard bearings. Slightly underspecified IMO, but if one wants to replace them, they're easily available.

A bigger problem is the blades - The factory blades were galvanized steel sheet metal and didn't last well. It'd be hard to find a set of those blades, me thinks, but possible. I think I still have a set of wood blades made for that machine...

Other common problems are a poor brake hub to mainshaft connection and a friction brake that often ices up.

Manuals are available and show the tail well enough to construct a reasonable facsimile.

Are you inclined to fix it?

[Kevin Baluha]

Neil thanks for your reply.
1. I think its a 24VDC model but i have not looked. Winter has come and unless we get some warm weather its on the tower until april very likely.
2. I am working to get a gin pole to aid in lowering the unit to the ground.
3. once i get it down to service it, I will determine if its merited to repair and re-install.
4. I am inclined to bypass/remove the internal diodes and do the rectification on the ground. This will reduce the wire size requirements and make it easier to service these parts.
5. The brake cable is broken near the top and will need to be repaired or re-engineered.
6. I am planning to either make new blades out of carbon fiber or fiberglass.
7. it is my plan to fix it and possibly to redesign it and make it the best of both worlds.

If you had one to play with - how would you improve it? Are you willing to part with your wooden blades?
Also our winds up here are possibly not ideal for a LARGE wind mill. We get very strong winds exceeding 130mph. County Code for wind load is 175mph for where i live.

your thoughts and support are all welcome and appreciated.

Kevin

[Neil Hochstedler]

Hi Kevin,

All good thoughts, IMO.

Dropping the power diodes to the ground is a good idea. The field diodes that often fail due to high voltage can be improved considerably by substituting a diode with a higher PIV rating. Pretty cheap, under $1 each. There are a lot of diodes in this machine, mostly reliable.


If you had one to play with - how would you improve it?

Ah, great question.

Offset gravity operated tail ass'y, wood blades on a flat plate instead of the variable pitch hub. (The hub is complicated and only prevents overspeed. It doesn't feather to optimize blade pitch) Said flat plate connected to the main shaft with a taperlock connection. (Present is just a straight, keyed connection that is prone to failure.)

No band brake - it ices up. No slip rings. (Drop a flexible cable down the middle of the tower and give it a drip loop up into the bottom of a junction/brake box that could also hold the power diodes.) No voltage regulator- there's a simple wiring change that gives the windings full field.

The front alternator and gearbox bearings are undersized, IMO. There may be easy ways to substitute more rugged bearings. Especially wimpy is the front alternator bearing. When it fails, the gear on the end of the alternator shaft bounces up and down on the main gear until the main gear breaks. And the main gear is not available off the shelf anymore.

Are you willing to part with your wooden blades?

Yes, I'd love to, if only I could find them. :-( I suspect I sold them with most of the rest of the Dunlite inventory. I do have a manual here I'd be happy to copy for you, with quite a bit of additional documentation.

Also our winds up here are possibly not ideal for a LARGE wind mill. We get very strong winds exceeding 130mph. County Code for wind load is 175mph for where i live.

Great tower, btw. Rohn 45G. One of the best for small turbines.

Maybe a lead for you: Bob Keller was an Enertech dealer and may have put your machine up. He was based in Boulder and I believe his company was called Mountain Wind. He had the rigging equipment to put this up by hand - gin poles, winch, etc. It's a long shot - it's been a long time since I heard anything about him.

Neil