I am attaching a sketch that relates to the text above
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hi, Sean
thank you for help. ))
that alternator is not from a car, just similar - with electromagnet on rotor, 3 phases.
it is designed to generate 50hz, 220 volts AC between phases at 3000 RPM, 4kW.
it has no thermistor.
with woodgas it is operating at 1900 - 2200 RPM, generating 100 -150vDC , 2 - 2.5kW.
the rectifier is full wave - 6 diodes, also big electrolytic capacitor battery is attached - 90X1000 uF.
(originally intended for a spot welder)
and incandescent bulb to discharge caps and avoid nasty surprises. ))
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Wow Tom! Thank you. I don’t know what to say, it’s a very generous offer. I hope you don’t mind storing it. I have to call Vern Swain and see if they have a steer axle for my old Michigan Loader. Swain’s is in Bellaire. I might be going there if I can get the parts. Otherwise, I stay out of lower Michigan. I don’t even go to the Buckley show.
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Thank you for the drawing Tone. The explanation is as I imagined.
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Hey here is a bit’o wisdom I try to pass on to Youths:
“if you ever find yourself the smartest person in a room . . . QUICK! Run out; and find a bigger room!”
The only way to be challenged, and truly expand, and learn. (Plus the easy-think Lazy always present will enslave you to do all of their heavy thinking. You, ‘Smart’. You will then be tempted to become their Guru/Priest destroying your humility. And then there goes your humanity. And you will become the biggest loser in that smaller-box room.)
Thanks guys for the being the bigger room.
Best Regards
Steve Unruh
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I would be very surprised if it didn’t have one. Just because they prevent overheating the coils and they are like a 5 cents. They are usually epoxied inside.
3 phases the phases overlap. similar to A on the bottom in the picture but the 3 humps overlap, so it never hits zero.
How is the capacitor attached? I assume on the dc side. does it connect the positive and negative sides together?
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Steve U,
Thanks for the wisdom. That’s a keeper.
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It’s been sitting there for 10 years Bruce. Just let me know if or when you want it. I’ll have to do some rearranging to get it moved. Don’t blame you for staying in the UP. I’d get out of here myself if I wasn’t so old. I’d probably go to Slovenia but I may not be smart enough. There’s some pretty sharp knives in that drawer.
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I blame him for not visiting us trolls! Don’t let him off the hook that easy! Geesh! j/k. 
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Lol! Youse are are a riot. I just got back from swimming in Lake Superior. Took my Dawn dish soap and washed all the grease off me. I spent the day building custom brake lines for the Blue Crew, using my hydraulic double flare tool. Damn, fellas, I have arrived, its really gonna be hard to drag me outta here. The boys are old enough now to drive across the lift bridge and shop in Houghton for me. I don’t even have to leave the island. And tomorrow is the Liberty Hunt, for which I have two tags…if it’s brown, its down!
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It’s raining these days and I had time to test the theory in practice, first I installed diodes (three-phase rectifier, where I used only half - three diodes) in the junction and tested the operation with the network, here the devices work well, (electric chain saw, angle cutter, inverter welding machine) the voltage is approx. 280V = direct. Then I installed this circuit on the “Fergie generator”, but here there was no expected result, surprised, disappointed,… I sat down on the thinking chair, drew diagrams and tried to find out the cause of the malfunction, the catch is that the current that it flows to the consumers only in one direction, it disables the “discharge” of the capacitors in the opposite direction,…
Mr. Steve was right when he spoke about intelligence,…
Now I installed a rectifier bridge on only one phase and tested the inverter welding machine, I used 2mm electrodes - 60A…it works easily, 2.5mm electrodes 80A…they also work at full power, then I tried 3.25mm electrodes. …120A, these also work, but there is already a lack of power (more than 3 kW of power is needed for the full power of the 3.25 mm electrodes)
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Oh that is brutal! It is only mid-september. Is the ice even off the Lake yet?
I didn’t realize you lived on an island. That must be nice.
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My friend Boštjan visited me and recorded some video content when I tested the generator, first welding with a 2 mm electrode, then 2.5 mm and a 2.4 kW saw…
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fantastic welding power , tone…and chainsaw running on woodgas!
bostjan has made a nice video, thanks, …is bostjans gasifier tractor finished?
yesterday i mounted the gasoline thank on the generator…
- will giorgio return to gasoline??
definitely not…
the foto gives the answer…
the old lombardini gasoline tank is now a protection box for the condensators…
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I have a old refrigerant unit the kind that sits on top of a trucks container to keep goods frozen and it has a motor in it that i could possible use as a generator , but its rpm is saying 1750 , would this still work ? if so i guess i need 3 capacitors but no idea the size or how to wire them up yet hoping the clever ones that have already done it will help me with some wisdom.
Thanks in advance .
Dave
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Dave since you operate at 50hz you’d spin it at 1450 rpm
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Chris posted a book for water turbines, I think in a thread called something like small scale hydro or something similar. And I -believe- that goes through most of the actual details as well as cap sizing. There might be a link to the pdf in that thread as well. It is probably in the homesteading section.
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Hello Dave, your motor will be good, I like it when I see the inscription on the plate that the connection is for a voltage of 380V, so you have a guaranteed zero in the center for single-phase consumers, your motor has an individual winding designed for a voltage of 220V (mine is for 380V ).
I don’t like the 1450 revolutions the most, which means that the motor is 4-pole, the nominal revolutions of an asynchronous motor are lower, it has a larger reactive component (yours has a cos fi of 0.8, mine has 0.89), and this also determines the size of the capacitors.
According to my experience, I would say that you need 3 capacitors connected in a star with a capacitance of approx. 50 microfarads, … be careful.
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Thank you all so far , Cody i will see what speed is needed once i can work out the caps and wiring of them ect, Sean i will head off to the library in a while and do some reading up.
Tone thank you for the cap info i shall set about looking for capacitors of the value mentioned 50 microfarads,@400 volts ? at this stage i am not sure how they would be wired together so i will see if i can find a local electrician before bombard you with lots of stupid questions ,you know what its like the first time you do anything on your own your always worried about blowing yourself up , so i will be looking and watching with great interest to take it all in.
many thanks all ,Dave
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Look for motor run capacitors.
Yes 400 volts or higher. Yes 50 microfarads.
The biggest help would be a picture of how they labeled the wires. You need to look for the center tap. You really need to find the center tap. You can’t really find it by measuring the resistance of the coils. I would approach it by a process of elimination. If the motor diagram shows the ∆ delta configuration, and the star Y configuration you can find the center tap by subtracting the delta connections from the star connections. What’s left will be the center tap and the center of the coils.
Looking at your photo, if you look for the 50hz connections, which is your frequency. Those look like the best way to find the center tap. I better draw a picture or have Sean search up a wiring diagram.
The caps are easy. Put the in a Y shape looking down at them. the center of the Y is where you join them to the center tap. The three ends of then Y join the corresponding three ends of the Y windings. To start it generating, arc a car battery across the cap with it spinning.
Also, remember the motor will only generate if you are trying to drag it past 1450rpm. It’s that struggle no faster when it can’t, that makes the power.
Tone was talking about the “PF” or power factor being .8 the ideal power factor is 1.0, I wouldn’t get too bunged up about that though. You will still pull out about a horse power from each leg.
I thought you had a big diesel generator already. I can’t understand why anyone would want to do this, if they already have a four pole generator.
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