Finally getting back to 3 hp conversion

[wildbill hickup]

Well this is an update on my 3 hp Baldor conversion. Started this several months ago set aside for the summer(and do to the frustration of trying to get the mags all on there)boy hat was a chore. Four poles 9 mags each for a total of 36(was going to be 40, but I broke one so to keep the poles even I removed one from each pole).

Still have to cleanup resin on armature.

Here is a shot of the stator housing and stator after pulling ends of coils to add 3 wires for a total of 12 as per Zubs instructions, and below shows the 3 new leads(red).

Last shot is the coil ends all tucked back into place and tied,taped, and shellaced back in place. All coils measure 1.3 ohms, they seem to be 2 strands each of some pretty fine wire(not sure what gauge maybe 20). Hope that resistance is OK.

 

Now all I've left to assemble is to figure out putting the armature back in the stator (without loseing fingeres), I remember the battle I had with the small 1/2 hp that's still flying BTW, and it only had 12 mags. Probably will use some king of a suspended come-a-long to lower the armature and tie the housing to a heavy table saw table. That's plan A anyway haven't thought of Plan B yet. I do hope everything fit's correctly as I don't rellish the thought of taking it apart.

I have a small lathe that I will be using to spin it up with and I will be posting #'s as soon as I get them.

Question: Is it best to get open voltage off one coil (at dirrerent speeds)and then calculate power from coil (using formula on Ed's site)to find out how I want to wire the coils for final setup, and to figure blade size, speed, TSR and so forth. I want this one to start pretty slow (almost always have 6-10 mph wind at ground level here)and peak (furl) at about 30-35 mph. I'm thinking 9-10' dia prop.

Well that's it so far!!

WIldbill

[MelTx]

   I think someone used his lathe to assemble an alt...Maybe the center post was taken off, and the stator housing was bolted to that...And the rotor was suspended between the chuck and a live center.By cranking the appron toward the chuck it slides the alt togather....Its a real buger to put those things together.MelTx

[ghurd]

That's 2 Thumbs Up Bill!

Hose clamps can help hold them down, but I honestly gave up.

Is it common to have 2 in hand factory wound?

G-

[johnlm]

"All coils measure 1.3 ohms, they seem to be 2 strands each of some pretty fine wire(not sure what gauge maybe 20). Hope that resistance is OK."

I don't know what kind of voltage you will be getting out of this conversion, or if you intend to use it at 12 or 24 V; but I suspect the 1.3 Ohms (dc R) will be a significant limiter on how much power you get out of it.  If the original operating voltage was 220VAC single phase you will likely see about 3 Ohms total impedance at around 450 RPM (Dc resistance + Inductive resistance).  So lets assume you are getting 40V DC output at 450 RPM (a guess here on my part, it may be much more or less) and want to charge 12V batteries.  The amount of current you will get will be (40V-12V) / 3 Ohms = 9.33 Amps and 112 Watts.  Not really a big amount for such a large motor.  If you were charging 24V batteries you would get 5.33 Amps and 128 Watts.  The higher the RPM the more impedance you will get.  If you get higher voltage at the 450 RPM I arbitrarily selected the amount of current and power will be higher.  Note my estimations are for single phase, but since you brought out 12 leads, maybe it was a 3 phase motor and you will be using it as a 3 phase alternator.  If so the numbers will be different but the impedance will still be somewhat high to get a significant amount of power.  I may be all wrong on this and it might do better than I suspect with all the magnets you were able to stuff in there - it must have been a buger to do that and hold them in place while you were glueing them.

John

[zubbly]

hi Wildbill!

first thing!  putting in these rotors of larger motors are quite dangerous. they have a lightning speed once the mags get attracted to the stator.

you need extra caution on your unit because of the internal cooling fan. what happens is once it starts to fly in, it will (for a split second) go past rotor/stator alignment, and then snap back to alignment. the extra travel will force the cooling fan fins into the winding cuasing damage.

here is what you can try.

if you have a very heavy workbench (make sure it is loaded up with about 300 pounds of stuff on it, or have a few buddys stand on the bench to give it extra weight. drill a hole in the bench, or block up for the rotorshaft extension that is longer than the frame of the motor. stand the stator frame vertical over the hole or vewrical on the blocking. then use 3 or more of those nylon binding straps they use to hold down loads on trucks. some have a little ratcheting tightener.

use a small boat winch or a ratcheting type chain hoist to lower the rotor into the stator frame. you could somehow chain the pully on the shaft to help lower it. or, you could drill and tap the end of the shaft for a 1/2 inch bolt and screw in a i bolt to attach chain. i also use that hole to hold my props on.

the attraction of the rotor into the stator would i guarantee take off your fingers if they got caught in there. glad you already realized this but had to mention it again.

with your 12 leads you can now connect 1 or 2 star, or 1 or 2 delta. i seem to find most 230/460 volt motors once converted, seem to match up cut in speed pretty good at 2 delta for 12 volt and 1 delta for 24 volt. they do vary a bit.

i think it was ghurd that asked if more than 1 wire in hand was common for factorys to wind motors with. anywheres from 1 to 20 wires in hand is common.

good luck and really look forward to hearing how your conversion works out. my guess is a minimum of a 10 foot prop with tsr of 6 or 7.

have fun

zubbly

[nothing to lose]

For those of us with lathes that is probably a great idea. Thanks for mentioning it.

 I hadn't thought of doing that with mine.

Should be able to use the lathe lead screw basically as a jacking screw to carefully slide things together in a slow controled fashion with good adjustments with the cross slide too even. Maybe even pull them back apart again if needed.

Provided the lathe is strong enough for the work. Seen some I would not trust with a 16" daul rotor though. Might twist the bed.

I should have tried this with my last conversion, probably would have saved some sore fingers here.

[nothing to lose]

Dang Zubbly,

 The pull on these are really that bad?? I know there is alot of pull on the smaller ones and of course I expected alot more pull when I do bigger ones, but I never expected it to be that much.

I think you just saved me alot of problems if I remember this later. I still have that big baldor I plan to convert one day, been scared to mess with it for some reason, geuss I know why now

 Actaully not scared, just still messing with smaller stuff before I try that big one.

[wildbill hickup]

Thanks to all for your ideas.

Meltex I have a lathe but it's rather on the small side (20" bed) and I think it will be easier to set up the slig and come-a-long basicly discribed by Zub in his comment.

NTL That 1/2 hp I mention (with only 12 mags) bit me hard enough that I won't forget it. No real damage just sugnificant pain( kinda like the old 'hitting the wrong nail with the hammer' trick) You'd really rather not do it again!!! Particularly with something alot haevier and 3 times as powerful. I just imagined my fisical pain and damage scale and multipied the results X3 to conclude I'm gonna keep the fingers out of this one. :-) Gotta calculate everything you know!!!

Ghurd I assume you are refering to the individual magnets. My responce on several occasions was %&^R$%&^%^%&&^%&%&^&&^%&^&^(^*$%^&T&^.,,,,,,,,, and that was with hose clamps!!!!! To put in a more civilized tone " It was a challenge ", but as my wife would agree I am one stubborn SOB and I wasn't going to let those little pieces of magnet and that hunk of steel win!!!

johnlm I appreciate the calcs and yes this is a 3 phase motor. Specs listed on tag are 9.0A @208V; 8.6A@230V; 4.3A @ 460. So I guess I'm just going to put it back together and see what happens. I'm tenitivly planing a 24v system using 10 deep cycle Bats that are all 3 years old and seem to be all about the same condition. Got them free, they came out of an off grid solar system. The guy replaces his bats every 3 years pass or fail. I haven't done much testing on them yet but voltage readings on all, as is, were within .1 volt, what the hell even if I lose a couple they were free.

Zubbly Yep I got the lightning speed thing on the 1/2 hp. Glad I built that one first as I never thought of the attraction til just a fraction of a second before it was to late(well it was to late,OUCH). I can definatly imagine loseing a couple of finger tips on this one. However I hadn't thought of the cooling fan thing. Thanks for the heads up.

I pretty much have figured on doing it the way you discribe. The table saw refered to is an old heavy belt-drive 10" probably about 200lbs and I can easily come up with another 100lbs or so of junk to pile on it. It has extentions that have plenty of holes for thr shaft to extend though and also for clamping,straping,tying the stator housing to. I will suspend the armature by the pully using a strap (that you refered to) and a come-a-long to lower it into place. This seems to be the easiest to set up (easier than setting up my lathe which I don't think is big enough anyway).

as far as the configuation I guess I'll just wait til I spin it up and see. ONe question though. Do you recommend the use of the PVC type blades to make a blade 4 or 5' long? I have a piece of 6" green PVC that I would like to cut 3 blades out of, at least for starters. I'm running a set of 2' ones on the 1/2 hp and I think they're great. Start in less than 6MPH (minimum reading on meter) and cut in at about 8 or 10. They seem to self regulate and I guess you would say stall at about 35 mph. I just wonder if they will flex to much in higher winds if they are longer.

Well thanks for all the help

Wildbill

[zubbly]

hi Wildbill!

pvc blades. just my thoughts. originally i was cutting blades from pvc. it was a quicky way for a set and also learning at the same time. i progressed to wood, and frankly i don't think i would use pvc for larger blades such as you will need. some people like it, some don't. i do have a set of blades that are 6 foot long each to make a 12 foot prop, cut from 12 inch diam green pipe and about 3/8 inch thick. they may work great, but after observing larger wooden sets in action, i would be scared to put these on.

if you would like the blades, you may have them free of charge (you cover the cost of shipping from my location in canada). if you like, i can take a pic of them so you can see what they are like. they are just cut out, the leading edge has not been rounded and the trailing edge has not been tapered. but they are pretty stiff because of the 3/8 inch thickness.

i just want to take a guess at your output of the gen.  i think 2-3 kw will be no problem.

have fun and wish you a merry christmas and a great new year!  

zubbly

[wildbill hickup]

I'd love to see a pic of them and if the shipping is not to much may take you up on the offer(right now I'm very short of cash.). What would the shipping be say UPS ground to 05867(or give me your zip and I do the research). I will probably just use them initialy for some basic windspeed tests, may also try cutting them down a bit. Eventually I would like to use a set of Arts blades or maybe those that you have been working on. Have you found a place to produce them for you? You can email me the pics if you want.

Note about email of natually replace the at with @ and sometimes you can't see it but there is an underscore "_" between wildbill and hickup. Thanks again for the offer.

Wildbill

[anchor1]

If you are planning on taking it apart more than once its worth making something like this pic works real good only took about an hour to make. Use 2 hose clips on each end and heavy reinforced hosing it stretches a bit but has never let go (yet).

Also a nut sandwiched between the two boards .

[zubbly]

give me a couple days to dig them out and will get a pic on here or email to ya. i will also take to ups depot for weight and get price on shipping.

zubbly

[wildbill hickup]

I assume that shaft is allthread correct?

[anchor1]

Yes allthread ,old fishing reel handle,and a bunch of washers under the hose, two or three bearings on the end would be better though, just screw the motor down with big washers they,ll never come out.

Mike

[wildbill hickup]

Cool idea, I'm hoping this won't have to come apart for a long time, and for now I'll put it together with the sling and table saw. However when the day comes (and I say when not if) I'll just build that little armature puller of yours, maybe even take the time to make that 'center of shaft' adustable up and down so it can be used on all machines just by adjusting and exchanging hose for different shaft sizes.

Great Idea!!!

Wildbill

[anchor1]

As it is you can move it up and down about 3 inches with the flex of the hose.

mike

[zubbly]

hi Wildbill!

i took 2 pics of the 6 foot blades today. i posted them in the irc phoyo gallery.

you can see them here:  http://www.anotherpower.com/gallery/zubbly?page=24

they weigh approx 30 pounds total. it might be just after christmas before i get a chance to check on shipping.

zubbly

[wildbill hickup]

They look pretty good. I looked you up on the Frapper map and got some rough calculations on shipping. I won't be able to do anything until after the first of the year(money shortage around Christmas you know) so don't bother doing a bunch of running around on my account. How ever I do think I would like them and I could send some money around the first week of the new year. If there is a Fedex near you that would be perfect as they are cheaper and seem to handle the freight much better than UPS. Once again thanks for the offer contact me by email at wildbill_hickup@yahoo.com when you get the final dementions and so forth.

Wildbill