Jacobs doesn't seem to be generating enough?

[Tom Sullivan]

I've had the Jacobs 1800 watt up for several weeks now, and am generally happy with production.  It is almost never sitting still.  Larry, my partner on this, was really impressed with my blades, as low end production seems excellent.  Actual generation in very low winds is pretty low (5--10- amps), but Ive seen pretty consistent 20 amp generation in better winds.  What has me and Larry stumped, is with really great winds, we rarely go over 25-30 amps, and this is capable of 60 amps??  We have never seen the flyweights come out, so they are not limiting the production.  I set the blade angles at 4 degrees at the root (the book says use a template supplied with the generator, which I obviously don't have).  I'm starting to get concerned with my blades now, or maybe the blade angle is wrong?  Anyone have ideas?

Tom

[DanG]

A little more information please? Drop lead AWG and length? What load are you powering when taking amperage measurements? Thanks!

[B529]

Tom,

what voltage are you running? How do you have the field wired?

Are you peaking at 20-25 amps in higher winds, plus 30mph winds?

A short case should max at about 45 amps +/-.

Do you have anemometer on your tower?

Kevin

[Tom Sullivan]

Larry has the voltage max set at 25 volts right now, but it's never hit that high yet anyway.  No anemometer on the tower, but I would have seen 3k-5K out of the Breezy in the same winds we are getting today.  The location or tower height shouldn't be a problem.  The highest output I've seen is about 30 amps at just over 20 volts.

The tower is 140', with 6 ga copper the first 60', then 2 ga aluminum the remaining 85' to the disconnect at the base of the tower.  It's 100' to the control panel in my garage, fed by the same 2 ga aluminum.  I have 6 ga running 12-14' from the control panel to the 1200 watt low voltage heating element, located in my solar tank.

Tom

[dnix71]

240 feet of cable may also be limiting what you can use. Have you thought about making ac at the base of the tower? Does the Jacobs have rectifiers on it, or is it wild a/c?

[B529]

Larry has the voltage max set at 25 volts right now, but it's never hit that high yet anyway.  No anemometer on the tower, but I would have seen 3k-5K out of the Breezy in the same winds we are getting today.  The location or tower height shouldn't be a problem.  The highest output I've seen is about 30 amps at just over 20 volts.
Tom

I don't understand the 30 amps @ 20 volts, are you not hooked up to a battery bank?

[Tom Sullivan]

We are hooked directly, through Larry's controller, to the low voltage heating elements.

   After further discussion, Larry indicated he thought the flyweights may be coming out, which would give us the "governor effect" we seem to be getting.  I got out my binoculars and watched it for some time, and that looked like the problem.  I took a photo of the turbine in a good wind moment, downloaded the photo on my computer and blew it up.  Sure enough, the flyweights are coming out, turning the blades to dump wind.  I also noticed a noise similar to when I feather the prop on my plane while doing my run-up before flight.  The blades get instantly louder when hitting the point we stall at 25 amps.

   I pulled out a copy of the original Jacobs owners manual, but there is not much guidance for flyweight adjustment (adjust no more than 1/4" on the bolt threads from the factory "preset" setting).  I adjusted them to "about" the stting they were at before rebuilding the hub.  Anyone have a procedure for this?  I hate to drop the turbine and be guessing on the amount to get it to where it needs to be.

Tom

[B529]

We are hooked directly, through Larry's controller, to the low voltage heating elements.

   After further discussion, Larry indicated he thought the flyweights may be coming out, which would give us the "governor effect" we seem to be getting.  I got out my binoculars and watched it for some time, and that looked like the problem.  I took a photo of the turbine in a good wind moment, downloaded the photo on my computer and blew it up.  Sure enough, the flyweights are coming out, turning the blades to dump wind.  I also noticed a noise similar to when I feather the prop on my plane while doing my run-up before flight.  The blades get instantly louder when hitting the point we stall at 25 amps.

   I pulled out a copy of the original Jacobs owners manual, but there is not much guidance for flyweight adjustment (adjust no more than 1/4" on the bolt threads from the factory "preset" setting).  I adjusted them to "about" the stting they were at before rebuilding the hub.  Anyone have a procedure for this?  I hate to drop the turbine and be guessing on the amount to get it to where it needs to be.

Tom
(Attachment Link)

Tom, sounds like your generator is OK, unfortunately you might have to raise and lower your tower a few times to get the fly ball spring tension right.  When I had my DC Jacobs up with a blade actuated governor, probably climbed the tower and adjusted the governor springs 4-6 times to get the rpm/amps right.

I don't have the knowledge to understand the loading effects of having it hooked up to a controller/resistive load compared to batteries. Would be interesting to hook it up to a 24v battery. Is the controller/load going to be your permanent set-up?

Kevin

[ghurd]

Do you have more info about the controller?
G-

[jacobs]

You need to set your 4 degrees initial pitch at the tips of the blade, not the root. That's probably the reason for the lack of performance.

Never tighten the flyball springs tighter than what the factory originally set them. The factory setting is 7 to 10 threads showing above the nut. The flyball governor is cast iron. It's very durable in it's stock form but easily damaged if spun faster than designed or by using heavier blades.  Many flyball governors have been destroyed over the years by over zealous folks trying to obtain more output and by lack of maintenance. Flying blades and large chunks of cast iron can kill. It's not something to play around with.

[Tom Sullivan]

Tom, sounds like your generator is OK, unfortunately you might have to raise and lower your tower a few times to get the fly ball spring tension right.  When I had my DC Jacobs up with a blade actuated governor, probably climbed the tower and adjusted the governor springs 4-6 times to get the rpm/amps right.

I don't have the knowledge to understand the loading effects of having it hooked up to a controller/resistive load compared to batteries. Would be interesting to hook it up to a 24v battery. Is the controller/load going to be your permanent set-up?

Kevin
[/quote]

Kevin,

Thanks for the feedback.  The more I look and listen, the more I'm sure this is a governor issue.  Larry, the owner of the actual generator and controller, is the one I am deferring to for the electrical aspects of this machine.  That's not my area of expertise.  He has built several turbines, several hydro generators, and was the lead PE / EE for one of the largest electrical contractors in the Midwest.  We did have the unit wired to a 24 volt battery bank prior to wiring to the heating element, and the output limitations were the same then.  

Do you have more info about the controller?
G-

Ghurd,

I have a picture of the controller below.  This was built by Larry.  If you want more details, I'll try to get him to respond, as noted above, this is over my head.

Jacobs,

Thanks for the information!!

[Tom Sullivan]

Sorry,  here is a picture of the whole controller

Tom

[SparWeb]

Hi Tom,
You say it's turning quickly, and the fly-balls are out.  Gotta agree!  I also see whirling blades in that picture - but by the looks of it fairly bright day for a picture.  Your vantage point is rather far away, too.  In this condition I would expect a digital camera shutter to be opening at about 1/500 or 1/250.  Blades of my WT are usually sharp, unless I work the shutter to show a whirl, or it's pretty dark.  So why are the blades so blurred in your pic?  High RPM, of course. 

As to why it would turn so fast, yet produce so little, I suspect the answer is that there is too much resistance in the entire system.  If you've tried both batteries and a heating element, then it could be the total length of wire between generator and load.  Your wire run is a combination of sizes and materials, so maybe you should calculate the resistance in a single line.  Better yet, measure it with a sensitive ohm meter (trouble is you have to lower the tower to do that).  Then multiply the resistance by the square of 25 amps as you show on the gauge, (625) and multiply all that by 1.73.  (1.73 * R * I^2 )   That's the power being shed as heat through the wires.

Next thing to check is the continuity of both phases.  Put the multimeter across two of the three phases (with the turbine running), each in turn, and see if the readings are very similar.  You have to make some account for changing wind speed as you do this.  In heating element loads I don't know how much this fluctuates with speed, but with battery charge it goes up and down a bit.  Any OBVIOUS differences should alert you to an under-performing phase or bad wire.  While testing this check for voltage from each phase to ground (or a tower leg or something) to find any "leakage" that may hint of chafed insulation.

You have a bunch of trouble-shooting to do, no matter what.  I'm sure you can sort it all out!  We're here to help if we can, too.

[Shadow]

Hey Tom,
  I never did get around to congratulating you on your finished machine, it is a beauty for sure!
 I'm not sure if its any help comparing it to mine but I can give you my figures to related to.

Not sure if you remember but mine is a dual commutator 110 volt, that we seperated the field coils into 2 groups of three and paralled the brushes to cut the voltage in half.

My blades(original Jacobs) are set 4-5 degrees at the tips, and the governer weights have 12 threads exposed. 

I have yet to see the weights in action, and I've studied them often, but I can always hear them just like you describe with your plane. Kind of a softer flutter.

In winds around 30 mph, I get 60 volts, depending on battery condition  and max I've seen is 42 amps. Then I hear the flutter and often some yaw one way or the other.

This all seems consistant with what its rated for.Close to 2500 watts. And most any day of the week its putting out at least 8-10 amps in light winds.

WE are on our third day now of 30-50 mph winds I've constantly seen high 30 amps most all day. This thing has been putting out better than my last girlfreind.

I learned alot putting mine together , from previous poster 'jacobs'. He helped me on a few issues and I spoke to him on the phone a few times. I agree with him I would try other things first before tightening down your governer weights.

Do you have 3 wires running down your tower? Where are the fields getting there power?  I'll see if I can find my numbers but I know the field coils needed a minumum amount of voltage?

[B529]

Hey Tom,
 
This thing has been putting out better than my last girlfreind.

Hope your next girlfriend has her governor springs set a little tighter to get max performance.


Tom,
Is Larry's controller, controlling the field?

Kevin

[ghurd]

This was built by Larry.  If you want more details, I'll try to get him to respond

I would be interested in the basic details.

Not sure what the VW Beetle cylinder does. 
G-

[Tom Sullivan]

  Thanks for all the responses.  To answer Sparweb first; my distance is due to the height of the machine.  I have to be quite a ways away, up on the second floor deck of my home, to get a picture anywhere near an angle to see the unit decently.  We will definitely measure the wiring resistance.  Larry didn't want to use the 2 ga aluminum to tie into the slip ring wiring, as it's difficult to work with.  He would have preferred 4 ga copper the entire way, but I couldn't justify a bunch more money in my wind turbine after the Breezy fiasco.  The wire I used was all free.  Not sure about the "three phase" issue.  I thought you needed three wires for that, yet this Jacobs uses just a positive and a negative for the large wires, and I'm using an 8 ga wire for the field.  Larry's controller does control the field of the generator.  The voltage regulator (VW Cylinder) is from a WWII B-17 or B-24.  Not sure how all that works, but then, as noted before, I rely on Larry for the electrical stuff.

  We'll drop the unit down soon; probably can't do it today though, as the wind is pretty high.  We're having a twelve year high in winds the last two days.  I can drop the tower in high winds; did several times with the Breezy, but then that unit could be locked up before dropping it.  My tail won't furl with the cable/spring system.  I figure the weight of 140' of cable is more than the spring can overcome to furl the tail.  I had planned on installing a "cable counterweight" at the top of the tower, but was hoping I didn't need it (blew that theory).

As I see it now, we need to check wiring resistance, blade angle at the tip, counterweight adjustment  (threads exposed) and I need to fix the tail furling system so I can furl it if needed. 

Again, thanks for the great response!!

Tom

[jacobs]

Closely looking at your photo, I just noticed your meter is only reading 15.35 volts. I don't know how you have it wired, but you need an absolute minimum of 24 volts to the fields to get the rated output of a 32 volt generator. Remember, the fields were designed to receive 32 to 40 volts. 15 volts is way too low.

[Tom Sullivan]

I had Larry review the responses, and he came over so we could do some tests.  He first disconnected the load (the low voltage heating element) and the voltage went instantly to 34.5 volts.  The turbine was basically being controlled for overspeed by the governor, and seemed to handle that fine.



We then hooked up a battery load; two 12 volt batteries in a series.  He seemed to remember better voltage with the batteries, and confirmed this with this test.



We discussed at length the blade pitch (clearly wrong) and the flyweight adjustment (not so sure that is off, based on the observation of Sparweb from my picture).  He also wondered if he was "loading" the generator too much with the current heating element configuration (less than 100% turbine efficiency due to blade issues, but loading the unit for 1800 watt output).  He rewired the heating element, wiring in the second one in a series.  We previously had only one element wired in.  That dropped the resistance in half (according to him) and the voltage went to 34-35 volts at high wind, with the amps still around 20-22 amps.  This effectively doubled the wattage going to the heating elements, but we are now at the top of the production on the generator at 35 volts.



He then bypassed the voltage regulator, hooking the field wire to the positive terminal with a jumper, and we saw 40+ volts and 1,000 watts to the elements.  He did this for just a short time, but I think we are at a point where further production will only be gained from blade adjustment and checking the flyball weight adjustments.

At least I'm up to 700-800 watts now in good wind, and will drop the tower as soon as it lets up.

Thanks for all the help!!

Tom

[DanG]

The tower is 140', with 6 ga copper the first 60', then 2 ga aluminum the remaining 85' to the disconnect at the base of the tower.  It's 100' to the control panel in my garage, fed by the same 2 ga aluminum.  I have 6 ga running 12-14' from the control panel to the 1200 watt low voltage heating element, located in my solar tank.

On output...
60' of 6 AWG copper at 24V would drop 10%,
185' of 2 AWG aluminum drops 24%
12' of 6 AWG copper robs another 2%
.... for a total of 37% power dissipating in the transmission lines.

That 800 watt peak you're seeing is closer to 1100 watts output before it touches the drop lines.

Also - know the field voltages are suffering the same fate but not the same percentages.

[jarrod9155]

It seems to me that the jacobs turbine is a very well  built turbine but in your case with a tower the size of your this might not work well if you need to be around 35 volts dc and travel that distance . I know first hand frustration with turbines and ther applacation to what you want it to do .I would think a diy turbine like alot of guys here build for high voltage 3 phase down the tower to the basement would have less loses in the line and could easly be dialed in for your heating element in your solar tank or grid tie . I personally travel about 200 feet to my basement from the turbine my dump load is a baseboard heater works great .
                 Just my thoughts for help if that Jacobs isnt working out .
          Jarrod

[SparWeb]

Haa what do I know - I totally forgot the Jake has a field winding, sorry.  Forget my wire calculations from before - Dan's got it done for you.  And it looks like a foot-note in Dan's posting, but his observation about the field voltage suffering from a drop on the long wires sounds like it deserves a calculation, too.  You may come up with a lot of missing volts on the field windings even though there are lots on your board.  How much current do they require?

[B529]

Tom, before lowering the tower, I would absolutely do one more test/reading with the resistor(s) out of the circuit with the generator/field going to straight to your 24 volt battery.

When I had my Jacobs up, I had the generator/field directly to the batteries, obviously a blocking diode in the path to keep the generator from motoring.  Worked great. This is how one of my neighbors had his as well for years. I know of a few others as well that are wired this way. I don't believe the controller/resistors is worth messing with, it's making it way more complicated then it needs to be. 

Kevin



 

[jacobs]

On a self excited shunt wound DC generator (Jacobs), the load should NOT be applied until the generator is spinning at battery charging speed. If the load is constant and always applied, It is difficult if not impossible for the generator to build rpm's and voltage to energize the fields. The easiest way to accomplish this is with a set of batteries, then divert the excess load.

You might want to consider wiring your fields directly to the generator output inside the generator case, then bring the generator positive and negative down through a reverse blocking diode and then to a set of 30 or 36 volt batteries. Have your friend build a diverter that diverts the excess power only when the voltage exceeds 35 volts when using a 30 volt bank or 43 volts when using a 36 volt bank.

If you wire it this way, I'm sure you'll be surprised at how well it'll then work.

[B529]

Looking at the wire size of your field on your control board, it's too small. You are adding a lot of resistance to your field, which is going to hurt your output. The original Jacobs controller added resistance to the field as the battery voltage climbed to control the battery voltage, which lowered the output of the generator.

Tom, get rid of the controller and listen to what forum member Jacobs suggested, he's been at this for a long time, hook up your field directly to the generator at the generator, hook up the generator to a battery bank.

I've been using a Morningstar TS-60 for a diversion controller for several years on my turbine, they work great. Have them on other turbines I've installed, no problems.

Kevin

 

[Ungrounded Lightning Rod]

You might want to consider wiring your fields directly to the generator output inside the generator case, then bring the generator positive and negative down through a reverse blocking diode and then to a set of 30 or 36 volt batteries. Have your friend build a diverter that diverts the excess power only when the voltage exceeds 35 volts when using a 30 volt bank or 43 volts when using a 36 volt bank.

That's the way to do it.

Then if it's spinning away at high RPM with no output and you need to "flash" the field, momentarily short the blocking diode.

[Tom Sullivan]

   I finally got time to drop the unit down today (been working on a log cabin project almost every spare minute).  We're forecast to have decent winds over the next couple days, so wanted to get the unit tweaked in.  First thing I found is the blade pitch WAS RIGHT.  My paranoia was unfounded.  Makes sense, since the unit seems to make power with almost any wind.  I noticed just the very slightest tower shake at low speed so checked it for balance.  Found I had to add 10 ounces to the base of one blade to get it perfectly balanced.  I tightened the spider gear a bit, and then tightened the side gears on two blades until every blade had zero movement in the pitch axis.  It was pretty minor before, but figured I might as well get it exactly right while it's down.  Rechecked the blade angles afterwards to ensure they didn't change.
 
    I checked the flyball weight adjustments and had between 5 and 6 threads showing.  Adjusted all 3 to 10 threads showing, as per earlier recommendation.  I went on the high side figuring for the springs being a bit weaker with age.  Checked every bolt and jamb nut on the unit for tightness while it was down.

Had the unit back up within a couple hours.  Had a bit of excitement raising it, but that's for another time to discuss.  Now just waiting on some wind to see if it's improved on the high end of output.

Tom

[SparWeb]

Had the unit back up within a couple hours.  Had a bit of excitement raising it, but that's for another time to discuss.  Now just waiting on some wind to see if it's improved on the high end of output.
Tom

Your tower is guy-wire braced isn't it?  Yeah I've wondered if there are any tricks to raising and lowering it.
Good luck, and good wind.

[Tom Sullivan]

Yes I have 2 guy wires at four locations, and an extra guy on the gin pole to tower connection,

   A few days ago, Larry rewired the elements several times, and wasn't happy with the production.  He went on line and read the details of the heating elements, since no paperwork was supplied with them.  He came over yesterday and rewired them again, and the production went up a lot.  He's way over my head on this, talking about "matching the impedance" or something.  He adjusted the voltage up on his controller after that too.  Anyway, the unit now is putting out 400-600 watts in wind that previously gave me less than half that.  The high end output has gone up as well.  Can't really say what the maximum output is, since the winds yesterday were decent, but not great.  Even so, the unit hit 1,000 watts yesterday without being anywhere near the winds I saw few weeks ago.

[Flux]

I have only just found this but I am completely confused about what you are doing.

I take it this is a 32v dc dynamo yet you are talking about load voltages round 20v. The field will not produce enough flux below 30v to get it operating properly.

Can you explain exactly what you are trying to do, are you charging a 24v battery or are you using some form of resistive load which you imply at times. What is the regulator doing? You won't get enough field volts anyway at 24v so there is no point in any form of field regulator and if it is sensing battery volts then it is not going to do what you want anyway, voltage regulated field control will decide your output by state of battery charge rather than available wind. As the volts rise the fiels will reduce until the blades run up to governor speed and the output will tail off and it will take forever to do the final charging.

Even when the 24v battery is below the regulator setting point you will have very limited field and the machine will just run fast and produce way below normal output.

Someone suggested connecting the field at the dynamo end, this makes sense if you are doing what I assume trying to charge a 24v battery. Doing it this way you will have battery volts plus cable drop at the dynamo and that will likely get you up near the nominal field voltage.

If you get full field you should get near rated amps but you will be way below rated power at 32v but it may still do what you want.

Flux

[Tom Sullivan]

No batteries.  The juice goes directly into the heating elements, varying in wattage from 100 watts to 1,000 watts (so far), depending on the wind level.  Basically, if the blades are turning it's putting power into the heating elements.  The regulator only regulates max voltage so it doesn't go past 45 volts.  The regulator doesn't do that completely by itself, Larry's got another gadget with a clamp that slides up and down the gadget  to "fool" the regulator (can be seen at upper left of an earlier post where I included a picture of his control panel).  He did connect the field directly to the positive and the output of the turbine was exactly the same.  He won't leave it like that because he can protect the generator with his current controls, but it was evident this made no improvement.  This is way over my head, it's his generator, so the controls are his game, and thus far I can't get him to respond to this forum.  I commented one time he was pretty confident about his electrical knowledge.  He corrected me and said he's plain arrogant (his words).  Anyway, I guess he doesn't want to get into a long dissertation explaining why this works.  I can say, the large electrical contractor he worked for doing electrical engineering still has him doing consulting work for projects today (he's 84).  Maybe I can get him to read this and respond.

[Flux]

OK  fine, now I know what you are doing.

It should work if you do it right.  I think you have established that the speed governor is set right, ideally you need to check rpm on no load to set it.

Below governor speed you will need to load the dynamo to suit the wind conditions. At governor speed your resistive load should be such that you reach about 40v and you should see about 45A. This would be roughly the condition it would see with a 32v battery, it should have full field at this point.

Unless your resistors let you get up to about 40v on full speed you won't get the full power out. In lighter winds with that value of resistor you will probably stall but in this case you can reduce the field to keep the prop operating on the peak of its curve, this is far easier than any normal resistive load controller that you would need with a permanent magnet machine.

I see no reason why this shouldn't work extremely well, you have the safety and peace of mind of the pitch governor so even if you loose load you have no problem and the ability to control the field gives you a simple way to keep the load correct in the lower winds. No doubt you will need to disconnect the load for start up as a shunt dynamo will probably not build up with full resistive load connected ( not in your speed range anyway).

Flux

[Flux]

Thinking more about this I suspect a shunt dynamo loaded by a resistor will be below critical speed for a lot of the time under these conditions, you may have difficulty running it self excited except at full load and speed.

Ideally you need separate field excitation and that could be tricky with no battery at all in the system.

I have no details of the controller, if it is pwm you may be able to maintain a stable field but I just don't have enough details.

Your starting point is still with value of resistor to give 40v at full load with governor operating. What happens in lower winds may be a different issue. The easy way would be to have a small battery charged by the mill and a dc converter to supply the field at variable voltage, the battery voltage could be 12, 24 or 36v but you would need some ingenuity to charge it reliably, it could be very small in terms of Ah.

Flux