The Lockridge device

Author Topic: The Lockridge device (Read 1279 times)

mbrownn	Re: The Lockridge device « Reply #75 on: 2012-05-02, 04:35:32 »
Newbie Posts: 246	Take note Are the number of turns on the motor coil and the generator coil the same? this is so we can calculate the ratio of turns required for the machine. If they are the same it is easier. Measure the voltage across the motor field coil and compare with the voltage on the generator field coil in both the loaded and unloaded conditions. Write it down as we may need to refer to these later.

Hiwater

Re: The Lockridge device « Reply #76 on: 2012-05-02, 21:07:51 »

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Posts: 137

Quote from: Hiwater on 2012-05-02, 03:54:14

I did do the test as you described in your post no. 57 . I see i made a mistake in connecting the ac and the voltmeter connection.

I will redo them in the am and post them. I never connected the scope up today. Will try tomorrow.

Going to reread your instruction in your post 57. I wonder if the output volt meter should be connected to the out put on the sec and ground. i was connecting it across the a and f terminals. Like you said. may be i did them right.

Need some clarification.

Did some tests on the stock Gm generator today. They will motorise pretty good the way they are. But if I connect like the starter generator theres too much resistance in the motor coil for it to rotate,just verily turns if i put power in the the free end of the coil. If i put power in on the brush where the other end of the motor coil connectds too spins up to speed. But if i connect both coils to the pos brush it would be like a center tap.Motorising on the residual magnetisim , then we woul have two charge coils to pull voltage off from. WHAT DO YOU THINK.

Hiwater

Re: The Lockridge device « Reply #77 on: 2012-05-02, 22:27:37 »

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Posts: 137

There 13 turns of copper ribbon the sta-gen. the stock one i checked were the same coils.
continuation of tests----voltage across motor coil locked 7.3-7.6 volts. motorised it was 11.7 volts. These tests are for the one i worked on yesterday. The sta-gen. With sec disconnected.------- The secondary ( gen coil) not loaded 3.3-3.4 volts ac. loaded with bulb was 0 volts.

Motor coil voltage, motor running across coil .1 volt--- from pos brush connection to gd--11.7 volts. Sec coil.--with out ac connected unloaded 3.9-4.o volts ac.--loaded 0 volts. with ac connected loaded 0volts. unloaded 15 volts ac.
locked across motor coil no ac .1volt. hope this is not too confusing to you cause it is to me. If you need clarification on something dont hesitate to ask me. everything ai all set up so i can go out and retes if need be. As i stated earlier i did the tests on the stock gen today all tests were 0 except for motor run no load which was 8 volts. dont seem to be much trafo action there.There was 4 volts ac across a-f terminals. Enough for today.

mbrownn

Re: The Lockridge device « Reply #78 on: 2012-05-03, 03:09:43 »

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Posts: 246

We are not getting the results I expected but that could be because it is drawing too much current with the standard motor coil of only 13 turns causing too much voltage drop.

The rise in voltage on the unloaded output coil can be expected, I forgot that the coil will have capacitance and so it will charge up like a capacitor.

If I understand you correctly, when you use a generator coil as the motor field coil, the Motor will hardly turn, Is that correct? If so we need to increase the voltage applied a little so that we have at least a few hundred RPM.

I will be more specific in the description of the tests so there is less confusion. Let us set up the motor so that it has two field coils that are 180 degrees apart and make both coils the same number of turns. You could use two generator field coils for this. Remove the other field coils as they will interact confusing the readings. One field coil will be wired in series with the armature and we will call this the motor field coil. The other field coil will be the generator field coil. The generator field coil will have to be electrically disconnected from the case so that there is no conductivity between the input and output. Apply enough ac voltage so that the motor runs. We need to compare the transformer action so we need to have the voltage reading across the motor field coil and the voltage reading across the generator field coil for all four tests. If you could so a scope shot for each test that would be really helpful

Test one = Motor stalled and no load. Obviously we have the capacitance problem here so we will need to put a resistor across the generator coil to prevent it charging up but the resistance needs to be high enough to allow the voltage to be seen. I would guess that a few thousand ohms would be ok. Post your results like this

Test1 Motor field coil xxx Generator field coil xxx and then scope shots and so on for the rest of the tests.

Test two = motor stalled with load
Test three = motor running and no load. again use the resistor
Test four = motor running with load

I know all this sounds like a pain in the butt, trust me it will teach us a lot.

Quote from: Hiwater on 2012-05-02, 21:07:51

Did some tests on the stock Gm generator today. They will motorise pretty good the way they are. But if I connect like the starter generator theres too much resistance in the motor coil for it to rotate,just verily turns if i put power in the the free end of the coil. If i put power in on the brush where the other end of the motor coil connectds too spins up to speed. But if i connect both coils to the pos brush it would be like a center tap.Motorising on the residual magnetisim , then we woul have two charge coils to pull voltage off from. WHAT DO YOU THINK.

There are many ways to wire a universal motor but we need the pulsing action and the best way to do that is series winding but by all means experiment as you may find something.

mbrownn

Re: The Lockridge device « Reply #79 on: 2012-05-03, 03:18:19 »

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Posts: 246

Quote from: Hiwater on 2012-05-02, 21:07:51

if I connect like the starter generator theres too much resistance in the motor coil for it to rotate

In a standard universal motor the second field coil is a compensation coil that lowers the inductance of the motor. we will be using this coil as our generator coil so under load you should get more speed than without load.

A standard motor setup is conductive compensation, we will have some Inductive compensation in our setup. http://books.google.com.ph/books?id=RRbIRBUQk-sC&pg=PA622&lpg=PA622&dq=conductive+compensation&source=bl&ots=QTXAY-mSv8&sig=cYZVYwZN_vqESAHGThi_FvttybM&hl=en&sa=X&ei=I-qhT-r2GYmQiAfC96HdCA&redir_esc=y#v=onepage&q=conductive%20compensation&f=false

Hiwater

Re: The Lockridge device « Reply #80 on: 2012-05-03, 17:36:44 »

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I got just a couple of minutes here, then back to work. Yes. in the stock generator using just one coil for the motor coil will verily rotate . very slow. I wii read the rest of your post this evening and print it out. The coil with the 13 turns is for the starter-generator not the stock generator.

These motors will rotat with out any feild coils in them at all with just the pole shoes residual magnetisim and the feild of the rotor.

Maybe dont need a motor coil to motorise except for the collapsing feild. Be back when I can.

mbrownn

Re: The Lockridge device « Reply #81 on: 2012-05-04, 09:06:32 »

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Posts: 246

That is interesting, I wondered about that and why the solid shoes and not laminated ones. It could be that this will play a roll in the overall workings of the device.

I know of a few possible circuits that the device could be, now I am trying to configure the geometry to make it happen but there are so many things involved so I still have a lot to learn. In the next few weeks and months we will reach the stage where we know more than anyone else bout this with the possible exceptions of Peter Lindermann and John Bedini.

One of the problems of the transformer effect is that it lowers the flux in the coils therefore reducing torque. This could be mitigated in three ways, the first being increasing the speed and there is some suggestion of this in Johns video when he suggests a speed of 6000 RPM. The second is placing a magnet in the magnetic circuit as this will increase flux but if there is significant residual magnetism we already have the magnet. The third is parallel path which I posted about some time ago. http://www.energeticforum.com/renewable-energy/7648-lockridge-device-original-parallel-path-motor.html Although the Lockridge looks relatively simple it is very complex in the interactions. Weather the Lockridge was parallel path or not remains to be seen but it is clear that if it wasn't, it is obvious that it would benefit from it.

For now we will test each section one step at a time so that we understand the complexities and pitfalls. Discovery is a process of trial, error and accident but in rediscovery we have the advantage of knowing some things already but there may be things we believe to be true that are not.

If you are able, it may be an Idea to wind a coil with say 50 turns of 18# wire for testing. In my universal motor I have use 30 turns of 23# wire.

mbrownn	Re: The Lockridge device « Reply #82 on: 2012-05-04, 12:28:10 »
Newbie Posts: 246	Wow, is this explaining the use of the capacitor in the lockridge as well as the gray motor? http://www.youtube.com/watch?v=im2TvLXW5bc&feature=relmfu

Hiwater

Re: The Lockridge device « Reply #83 on: 2012-05-04, 15:41:43 »

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Posts: 137

Quote from: mbrownn on 2012-05-04, 12:28:10

Wow, is this explaining the use of the capacitor in the lockridge as well as the gray motor?

http://www.youtube.com/watch?v=im2TvLXW5bc&feature=relmfu

This does explain a lot. the rpm of the motor has a lot to do with it. The ones we are working with the rpm cam be changed by the size of the feild pole shoe ( shorter and narrower ) but then the feild coil has to accomodiate the shoe. I have experimented wirh some. Like i said before I have one Motor that runs at about 10,316 rpms. I dont dare let it run any faster it starts shaking like it wants to lift off. This is a belt driven 110 volt ac generator i run on 12 modified. Like the one from powermite only mine is in a different style case.

Looks like a rain day so will get some time this afternoon to do the last couple of test you mentioned.

How do you want the coil wound . is it for the feild coil.

Hiwater	Re: The Lockridge device « Reply #84 on: 2012-05-07, 02:28:48 »
Full Member Posts: 137	Never got done what i had planned last week. New week ahead of us. Will try tomorrow to get the last tests done.

Hiwater

Re: The Lockridge device « Reply #85 on: 2012-05-07, 21:01:24 »

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Posts: 137

Test conclusions ----One stock gm generator. 2 feild coils the same. 4.7k ohms for load across gen feild coil. Motor coil in series with armature. Gen feild coil bothe leads brought out of case for testing.
Test 1--motor stalled no load--- motor coil 160.6 volts
gen coil 46.6 volts
Tes 2--motor stalled with load motor coil 160.6 volts
gen coil 48.1 volts
Test 3-- motor running no load -- motor coil 163.6 volts
gen coil 46.7 volts
Test 4--motor running with load--162.2 volts
gen coil 46.7 volts

these test were with the variac wide open - to the max.

Hiwater

Re: The Lockridge device « Reply #86 on: 2012-05-07, 21:13:36 »

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Posts: 137

Question. which coil did you want rewound, the motor coilor the gen coil. I did this about a year ago with a feild coil from a snow plow lift motor. It is about 2/3 the size of the gen coil we arwe working with. When used for a generator coil and a load put on it while the unit is motorising it will gain in rpm. the one i have gains 870 rpm. will rechech later today to make sure where I put the load for the gain.

I need to get an adapter fot the computer and a camera to use for the scope shots . i havent hooked up the scope to any of the tests yet. My daughter said she would come help me figure out what to do. as I dont have a clue what to do.

Hiwater

Re: The Lockridge device « Reply #87 on: 2012-05-08, 02:59:55 »

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Posts: 137

I tried to get the motor that gave me the 870 rpm gainto work today. But wouldnt cooperate with me. Dont know for sure but i think i had one of those armatures in there with the wide slots from the cub cadets. It wont work with the narrow slot armatures.I did find out that there two different armatures for the delco gens we are working on.

The winding is different and one is more effecient than the other as far as rpm. One is kind of wound in a spiral on the end opposite the commutator. the other is more of a cross over winding which i think is more effecient.

Should be able to get you some scope shots. daughter said she can take the pictures and run them through her computer, But might have to send them e-mail to you.
Got another project Ive been working on also. Unit goes silent, lost the effect, trying to get it back.

mbrownn

Re: The Lockridge device « Reply #88 on: 2012-05-08, 12:57:19 »

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Posts: 246

Quote from: Hiwater on 2012-05-07, 21:01:24

Test conclusions ----One stock gm generator. 2 feild coils the same. 4.7k ohms for load across gen feild coil. Motor coil in series with armature. Gen feild coil bothe leads brought out of case for testing.
Test 1--motor stalled no load--- motor coil 160.6 volts
gen coil 46.6 volts
Tes 2--motor stalled with load motor coil 160.6 volts
gen coil 48.1 volts
Test 3-- motor running no load -- motor coil 163.6 volts
gen coil 46.7 volts
Test 4--motor running with load--162.2 volts
gen coil 46.7 volts

these test were with the variac wide open - to the max.

I assume that the motor coil voltages were measured with the meter, how high was the voltage applied across the motor including the armature?

The voltage you are using is much higher than I expected, I thought less than 12v input would be needed to make it spin. Maybe it is the variac that cannot supply the current, motors use current to run not volts.

These results suggests to me that we have a low efficiency transformer action and little or no generator function, all in all about 30% efficient. that fits in with what is known about universal motor efficiencies.

Quote from: Hiwater

Question. which coil did you want rewound, the motor coilor the gen coil. I did this about a year ago with a feild coil from a snow plow lift motor. It is about 2/3 the size of the gen coil we arwe working with. When used for a generator coil and a load put on it while the unit is motorising it will gain in rpm. the one i have gains 870 rpm. will rechech later today to make sure where I put the load for the gain.

I need to get an adapter fot the computer and a camera to use for the scope shots . i havent hooked up the scope to any of the tests yet. My daughter said she would come help me figure out what to do. as I dont have a clue what to do.

Yes its the motor armature coil, the tests suggest that for the transformer action we would need a ratio of four to one but we do not know if there are any generator effects yet. Once we get generation at the same time as transformer action I am expecting the efficiency to go up or down. If it goes down then our generator action is opposing our transformer.

Quote from: Hiwater

The winding is different and one is more effecient than the other as far as rpm. One is kind of wound in a spiral on the end opposite the commutator. the other is more of a cross over winding which i think is more effecient.

If you find one please take pictures

Your scope is to all intents and purposes a graphical volt meter so set the voltage range above the voltage you can measure and then adjust the timescale until you get a waveform.

If you could apply about 6vDC across the armature and spin the device in the same direction as it ran with an electric drill this will give us an idea of the generator action. Don't forget to use the resistor then the bulb as loads measure any voltage output. in one field coil.

I was expecting about 6v input with around 3v output but having said that, with only a small load on the output there is no compensation on the motor so its inductance will be high. when there is a high load on the output we have inductive compensation reducing the impedance of the motor section. more current should flow and the motor should speed up.

The more I think about this I think the current limited variac may have given us false results. My variac is only 4 amps but the motor I am going to connect to it is only going to require that or less. Your generator could well be 10 amps or more

Now repeat all the tests and measure the output current and compare it with the input.

mbrownn

Re: The Lockridge device « Reply #89 on: 2012-05-08, 13:42:47 »

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Posts: 246

I just ran a test on my motor. 30 turns 23# wire on motor field coil, Resistance is too low to measure but is a lot less than 1 ohm. armature in position but not powered as I haven't got the brushes sorted yet. The input was 2v AC 3.6A or 7.2w

The generator field coil is the standard coil fitted to a 220v 400w universal motor, it is approximately 120 turns, 12 ohms + or _ 1 ohm. The output was 6.2v AC 0.5A or 3.1w

This would be a 50% efficiency although the meter accuracy on AC amps is plus or minus 10% on this range

Ok there was no current in the armature but it does prove there is a transformer action and we can step up.

I accidentally hit it with 250v when I switched on and the thing vibrated so much it moved across the table, luckily I switched it off before any damage was done. The motor windings are designed for 6 to 12v when running.

Based on your test I will rewind the generator field coil with 100 turns and remove turns as required when we start to get things working but I did want to see what the original coil would do.

Hiwater	Re: The Lockridge device « Reply #90 on: 2012-05-08, 19:51:20 »
Full Member Posts: 137	read the posts. The stock motor coil has to have 140 volts ac and 8 amps to rotate about 50 rpms a minute It will not ratate on 6 or 12 volts dc. way too much resistance. Was trying to get some test done using the scope. But the gen gets hot too fast. having a hard time to get the scope pattern on the screen in the right place before i have to shut it down. Will keep trying.

Hiwater

Re: The Lockridge device « Reply #91 on: 2012-05-09, 00:15:57 »

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Posts: 137

The 6 volt tests;
7.2 volts to excite motor feild coil
Test 1--- not rotating across motor no load
motor coil---2.2 volts dc
gen coil------3.6 volts ac
test 2-- not rotating with load
gen coil 4.7k ohms--- 3.6 volts ac and 12 volt bulb o volts
motor coil 2.2 volts both tests
test 3--motor spinning no load
motor coil 5.5 volts up from 2.2
gen coil---2.8 volts ac
test 4 motor spinning with load
motor coil 4.2 volts dc
gen coil 4.7k ohms 2.6 volts ac
motor coil 4.2 v-dc---12volt bulb and gen coil at o volts.

hope you can make some sense out of these numbers.

Hiwater

Re: The Lockridge device « Reply #92 on: 2012-05-09, 00:35:24 »

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Posts: 137

These test are like the ones the other day except these are the amp readings voltage about the same. It takes 140 volts to make that generator rotate at close to 8 amps.
Test 1 motor stalled no load motor coil 7.85 amps
gen coil open .7 one wire-- .9 other wire
wires connected 1.87 amps
Test2--motor stalled with load motor coil---8.06 amps
gen coil 4.7k ohms 0 amps
Test 3-motor running no load motor coil--7.2 amps
gen coil .4 amps
test 4 motor running with load motor coil 7.54 amps
gen coil.11 amps at 4.7k ohms ( on these tests if I use the bulb I dont get any reading on the gen coil) I used a clamp on meter for these tests. It has amps and voltage scale.

Hiwater

Re: The Lockridge device « Reply #93 on: 2012-05-09, 01:05:05 »

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Posts: 137

How much transformer action do you think there is in one of these generators. Dont seem like it does what we want it to do.

i did run one of these generators on an electric motor just to check the charging with out any power connected up to it. Darn near jumped out of my hands. so then i pit the generator on a frame wiith a flywheel to see if it would charge when i disconnected the power. No wont charge. think i have it running the wrong way. I know they will only charge one way . might be able to connect the cables the other way, dont know . it will free wheel for over 2 minutes at 4500rpms top and coasting down. So i want it to continue charging on the way down. the residual magnetisim in these as speed picks you dont need any power connected to them.

As long as we can have them charge in the direction they are motorised. so the armature reaction dont slow them down. We wanrt the armature reaction to help push the armatur in direction of rotation. Some food for thought.
Oh almost for got I tried the ac on one of my sta-gens it went to 39amps right now but it wanted to rotate right away. so i think youre on the right track by doing that coil like youre talking about. To get an even ratio of motor winding to gen winding. May a person could weigh them out to get the right weight distribution. Iv done that before works pretty good.

mbrownn

Re: The Lockridge device « Reply #94 on: 2012-05-09, 01:54:53 »

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Posts: 246

Quote from: Hiwater on 2012-05-08, 19:51:20

read the posts. The stock motor coil has to have 140 volts ac and 8 amps to rotate about 50 rpms a minute It will not ratate on 6 or 12 volts dc. way too much resistance.

Was trying to get some test done using the scope. But the gen gets hot too fast. having a hard time to get the scope pattern on the screen in the right place before i have to shut it down. Will keep trying.

Wow 140v at 8A to get it to rotate at 50 RPM? that's 1120 watts, something isn't right there.

I assume it is a 12v generator, what is the resistance of the field coils? best to check the resistance of the armature too, maybe there is a break or short somewhere.

If it is a generator the brushes will be in the wrong place for motoring which would reduce its efficiency but I would not expect such a big difference.

Quote from: Hiwater

The 6 volt tests;

7.2 volts to excite motor feild coil
Test 1--- not rotating across motor no load
motor coil---2.2 volts dc
gen coil------3.6 volts ac

If this test was with a resistor across the output and the motor and generator coils are both the same, it is very interesting as we have a voltage gain. The rest of the first tests makes sense and is what I would expect but your second set of tests just don't make sense to me as there is little correlation. something isn't right.

Try reversing the polarity of the motor field winding and see if that does anything

With the motor stalled we have only the transformer action and the action of the magnetic field of the armature coil so we should get an output voltage and current. the lower the load, the higher the voltage with the current being opposite. With the motor running we should have either a cancellation of the voltage or a gain with the same thing happening to the current.

I wonder if there are any diodes or anything built into the windings?

I think we need to check the resistance of the armature and field windings, do it in both directions, it should be the same.

Hiwater

Re: The Lockridge device « Reply #95 on: 2012-05-10, 15:41:17 »

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Posts: 137

I did retest on the 6 volt application yesterday. the tests are conclusive. there is a modest gain. So we know that part.

I used another variac for retestin a couple of the ac tests. Across motor coil 135.0 volts ac and the sec was 48-50 volts. if i put too big a load on the sec the voltage drops to zero, Motor a gen coil 3.6 ohms each..armature resistance.2 ohms every section. Amps across motor coil 6.81 stalled. running was 6.23 amps.
dont make any difference in opposite rotation.
Works better with other variac. still cant get the scope pattern on the ac. Spikes are from top to bottom of screen. I think it works ok on the dc though. Been working on the camera. Trying to get it setup for e-mailing pictures.So going to attempt to send you one picture through your pm e-mail. then you can reply letting me know if you got it.

mbrownn

Re: The Lockridge device « Reply #96 on: 2012-05-10, 16:49:34 »

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Posts: 246

With such low resistances the problem is obvious, the variac cannot supply the amps required at 100+ volts hence the false readings. You will not be able to run the motor on the variac and get good readings at this voltage.

Drop your AC volts to about 2 to 4v and read the output like I did. Your resistance suggests you should only be drawing about 1.5 amps at 6v. I don't understand why you cant get it to run on the variac at a similar voltage and ampage.

I have come up with a circuit to use an unmodified motor and I can get it into overunity on the simulator with the specs of one of my motors. http://www.falstad.com/circuit/#%24+1+1.0000000000000002E-6+47.65948060424672+59+5.0+50%0Al+576+224+528+224+0+0.015+1.7718478901136514%0Av+896+384+896+224+0+0+40.0+250.0+0.0+0.0+0.5%0A178+704+272+736+272+0+2+2.0E-9+7.3E-322+0.05+1000000.0+0.02+20.0%0Ac+704+272+672+272+0+5.0E-7+32.55977998047937%0Aw+736+256+816+256+0%0Aw+816+240+816+256+0%0Av+864+384+832+384+0+0+40.0+12.0+0.0+0.0+0.5%0Aw+816+240+736+240+0%0Aw+736+288+736+528+0%0Av+704+304+704+320+0+2+100.0+5.0+5.0+0.0+0.5%0Ad+896+528+736+528+1+0.805904783%0Ad+896+208+864+208+1+0.805904783%0Aw+896+384+896+416+0%0Aw+896+416+896+448+0%0Aw+896+448+896+480+0%0Aw+816+256+816+384+0%0Ar+832+384+816+384+0+0.062%0Aw+896+480+896+528+0%0Ar+704+224+576+224+0+4.0%0Ar+896+208+896+224+0+0.8%0Aw+656+272+656+288+0%0Aw+656+272+656+256+0%0Av+656+288+624+288+0+0+40.0+100.0+0.0+0.0+0.5%0Av+624+256+656+256+0+0+40.0+100.0+0.0+0.0+0.5%0Ad+576+272+624+288+1+0.805904783%0Ad+624+256+576+272+1+0.805904783%0Aw+656+272+672+272+0%0Aw+864+384+896+384+0%0Ac+864+208+864+384+0+9.999999999999999E-6+274.4583382235312%0Ad+864+208+736+208+1+0.805904783%0AT+464+224+528+272+0+0.015+0.4+3.3306690738754696E-14+1.7718478901136505+0.999%0Aw+576+272+528+272+0%0Ap+464+224+464+272+0%0Ad+368+256+400+224+1+0.805904783%0Ad+400+224+416+256+1+0.805904783%0Ad+368+256+400+272+1+0.805904783%0Ad+400+272+416+256+1+0.805904783%0Aw+416+128+864+128+0%0Aw+864+128+864+208+0%0Aw+368+432+864+432+0%0Aw+864+432+864+384+0%0Av+464+272+400+272+0+0+40.0+250.0+0.0+0.0+0.5%0Ar+464+224+400+224+0+1.0%0Aw+368+432+368+256+0%0Aw+416+256+416+128+0%0Ao+3+64+0+291+640.0+3.2+0+-1%0Ao+1+64+1+291+7.62939453125E-5+9.765625E-5+1+-1%0Ao+6+64+1+35+40.0+9.765625E-5+2+-1%0Ao+0+64+1+291+640.0+9.765625E-5+3+-1%0Ao+28+64+0+291+640.0+3.2+4+-1%0Ao+18+64+0+33+5.0+3.2+5+-1%0Ao+32+64+0+34+640.0+9.765625E-5+6+-1%0Ao+41+64+1+291+320.0+9.765625E-5+7+-1%0A

I think we should investigate this option before we butcher any windings on your generator.

The gain on your DC reading could be good news or it could be a ripple, we wont know without a scope reading. Try taking a scope reading on this as your spikes wont be so high.

Hiwater	Re: The Lockridge device « Reply #97 on: 2012-05-11, 15:44:16 »
Full Member Posts: 137	The motor you are using for the tests. Is it a standard ac motor or is it a 12 volt dc motor. Trying to figure out why your volts and amps are down so low. There is some technicle glitch in the service provider. Just got off the phone with them. They are trying to remedy the problem.

mbrownn

Re: The Lockridge device « Reply #98 on: 2012-05-11, 17:52:43 »

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Posts: 246

It started life as a 400w 220v angle grinder but I have now replaced one of the field coils and rewound the rotor with similar turns to what I found on a 12v motor but with heavy gauge wire.

The voltage across a motor needs to be as low as possible as it is only the current that produces a magnetic field. Resistance produced heat losses under ohms law so the lower the voltage and resistance the lower the loss. Of course you have to apply enough voltage to get the required current under ohms law. With very low resistances we can make a motor run very well on just a few volts.

I have a 1.2Kw 220v motor that will run at around 800 to 1000 RPM on 12v, Its field coils are around 1 ohm. unfortunately there is a break in the armature coil so I get quite a bit of arcing on the brushes.

With your motor, whatever the voltage it will run on DC, divide it by 8 and then multiply it by 10 and that is the AC voltage that should make the same amount of current flow and the motor should perform almost the same.

I don't understand why your motor does not like AC, it should run on it with a single figure voltage. Your field coil is 3.6 ohms and your armature will be in a similar range. the brushes may be 3 to 6 ohms so with one field coil and the armature with the brushes you are probably at 10ish ohms. With 12v applied that would give you 1.2 amps. You said you were getting between 6 and 7 amps on 6 volts so your total resistance must be less than 1 ohm. I understand that cheap meters are not accurate at measuring such low resistances so I didn't say anything. To run your motor on AC divide 6 by 8 and multiply by 10 and you get 7.5 volts to get a similar performance. One possibility could be that your stator and field coil shoes don't like to change polarity because of the residual magnetism. To test this and do a transformer test we can use an AC supply rectified by a single diode. Observing the polarity that it runs on with DC apply the half wave rectified AC and see if it runs. Of course because you have halved the input we will need to increase the voltage again. If this does not work I am stumped. Residual magnetism may be a required factor in the lockridge so don't worry about it at this stage. If it is residual magnetism that is causing the problem then the last circuit I posted wont work on your motor.

One thing I have noticed with brushes, their resistance is higher at start, then drops as the speed increases a little then goes up as high speed is reached. Of course it isn't the brushes, it is how good the contact is with the commutator.

All these unforeseen problems are nothing to worry about, they help us learn about our motors and what they are capable of. Unfortunately little is on the net about what we are doing so we have to learn the hard way.

How high is the friction on your motor?

mbrownn

Re: The Lockridge device « Reply #99 on: 2012-05-11, 18:06:52 »

Newbie

Posts: 246

By the time we have developed this motor generator you will know more about these motors than virtually anyone alive, seriously I mean that and so will I. Almost every motor designer just follows the basics that are written in books and what is programmed in computers. They ignore what interactions we are looking to exploit and just regard them as a loss. Any energy that you can exploit in a motor is no longer a loss. If residual magnetism is a factor that we need, we have just turned a loss into a gain so while your results may be different to mine, we know one of the reasons.

If you run a universal motor on DC it is more efficient than on AC, I believe this is because we are not changing the polarity of the Iron in the stator and we know that the changing polarity is part of the iron loss. the other parts are hysteresis (what ever this is) and eddy currents. My motor should be better on eddy currents.