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ridelong
08-31-2008, 12:07 PM
All,

Thinking through what is needed, a temperature feedback PWM is the way to go.

1. The pwm would run full "on" until the generator got to the temperature
you set it to.

2. This would give maximum generation and get the gen up to temperature quicker.

3. Then the feedback loop pwm will apply as much current to generate HHO as possible, but will not let the generator exceed the temperature that it was set to.

3. The same circuit could be set up so if the car is off, the circuit could monitor the temp of the electrolyte, and turn on an electrolyte heating device if the electrolyte got below, say 35 degrees f.

I'm pretty excited about this one. Got about 90% of the stuff to make one.

Will report when finished.

ridelong
09-01-2008, 07:03 PM
All,

Finished the schematic.

Built a temperature probe to go in my gen, used .200 id 316 stainless 6 inches long, an LM35 celcius IC, and a 5/16 bulkhead / hosebarb drilled out to press fit the stainless. Hot melt in / on both ends to seal it.

Start breadboarding the circuit tomorrow.

DigitalMocking
09-01-2008, 07:20 PM
The smith/plumbabob design produces no heat really, I put one together at the garage today and it worked fantasticly well, putting out about .8lpm @11 amps, no heat, and we left it running for 3 hours.

But almost all the other designs really do need a temp PWM, I can't wait to see your schematic. I was a DS in the navy, but that was 20 years ago and a lot of my circuit design skills are locked away by many many beers. I'm trying to wrest them free, but it's not easy.

Q-Hack!
09-01-2008, 10:27 PM
Share, share... I am learning a lot from you. :)

h2ocommuter
09-01-2008, 11:32 PM
I am getting thermal run away with any electrolite at all within 30 min. (1/4 tsp in igal. distilled water)

it is beyond my testors at 10 amps and probably 175 degrees real hot; It produces 1 Qt gas in nearly 7 min that way.

I have less than 9.5 sq. in. in it though I Plan on building another with 1000 sq. in and I need some controller to limit the amps.

as I said in my other mail to you I want to build a signal that will reverberate the water at different frequncies that will dislodge the hydrogen using sound waves.

That is concidered Not Brute forse.

Thank you so much

ridelong
09-02-2008, 06:35 AM
h2ocommuter,

I tried to get more generation by varying the frequency and duty cycle of the power supply. Ran from 10 hz. to 150khz., 10% to 100% duty cycle. Never got the system to generate better than straight D.C.

ridelong
09-02-2008, 08:31 PM
Got the ss probe mounted in my gen.. Went to hook up the probe and the output wire jumped right on to the + supply....poof. Start building another tomorrow.

h2ocommuter
09-02-2008, 09:37 PM
Carefull,,, I am slow at my verbatium so I will only refer you to what I believe to be the key answers to the resinance delivery of electricty.

First seperate systems of pulse width, frequency amplitude and modulation are just the start in building the spacific type of PWM that Stanley Meyer designed.

he used winding coils to amplify the kz output and one thing he says in a lecture and in his writings is the water cell is like a capacitor! "simily" it is like a capacitor.

David wenbert understood that when he talked to Blog talk radio.

Kow I am by far not perfict in the english language but a simily is absolutely not the same thing as "is a capicitor. Moreover Stanley Meyer used somthing called Delron to cover the cathode so it fully insulated it from conducting any electricty.

So in my humble opinion the cathode is only in the water to controle the magnetic electricle waves sent by the anode.
OK?

h2ocommuter
09-02-2008, 09:50 PM
Please be carefull with that equipment I would like to buy one of them from you to test install on a number of my electrolizers so that I can go into production and finally start making some money.

I am scared of making a mistake on building my own until I get a little more understanding and knowledge.

I am having good luck in my electrolizers but I am having thermal run away in just a short while.

I am using strait distilled water and getting medioquer output. (Just average)
But I feel with your design I could at least controle the amperage and heat very well.

I know you must be good with your wiring but use more caution thoes things you are building are vasluable.

I have been building elecctrolizers for 6 mos (only 2 are nearly Identicle) and each one though it produced good output they would all get thermal runaway if I pushed the limits.

I will not sell these things if I cannot make it easily manageable.

and besides that I would have to babysit each of my sustomers vehicles.

sounds like a lot of pissed off people if I did that.

ridelong
09-03-2008, 06:43 PM
all,

Got the probe fixed, and it seems to measure the electrolyte tempreature OK.

Going down to start breadboarding the circuit now.

Hope the loop response is fast enough, possible it will oscillate slowly, not good. Will find out in a few days.

ridelong
09-03-2008, 08:45 PM
Got the circuit built. Fired it up, looks like it works, but much testing to do.

sp1r0
09-03-2008, 09:26 PM
Man I wish I made it through Drexel. EE's rule!

ridelong
09-04-2008, 06:55 PM
Fired the temp feedback circuit up, set it to 100 deg f.. Bottle working fine start at 6.5 amps around 90 deg drawing 9 amps.

When it hit setpoint it went goofy. The probe should read 400 mv, it shot up to 900 mv and floated between 700 - 900 mv..

In my attempt to find the problem I shorted out the fet and blew it.

Figured that was a sign, so I quit for tonight.

Will replace fet and start again tomorrow.

ridelong
09-05-2008, 08:08 PM
Replaced the fet, still getting nonsense output voltage from the temp sensor. Worked on it a little this afternoon, it's something to do with ground layout.

Will put on my engineer hat and work on it this evening.

I wish this one went as easy as the current feedback one. Oh well, problems exercise troubleshooting skills.

Jaxom
09-06-2008, 08:37 AM
If it was too easy it wouldn't be fun. ;)

donnylynn
09-06-2008, 12:57 PM
Got the circuit built. Fired it up, looks like it works, but much testing to do.

one question about your idea. If you are using temp as feedback for the pwm, arent you concerned about lag time? Once an electrolyzer gets hot and hit your set point, it will take several minutes to cool enough to turn the pwm pulse back on. Unless you are using the signal to toggle between full on and some reduced mode of operation/reduced current???

I appreciate the current limit circuit you posted. Much simpler than the others I have seen. I believe in K.I.S.S.

ridelong
09-06-2008, 04:33 PM
donnylynn,

I am concerned about the lag time, it could be a real problem. If the cycle time is less than 1 second, I think the circuit will work.

If it gets over 5 seconds, it will be a problem. I don't know what I'll do with the circuit then.

I could use it for controlling a heater in the winter.

donnylynn
09-06-2008, 05:41 PM
donnylynn,

I am concerned about the lag time, it could be a real problem. If the cycle time is less than 1 second, I think the circuit will work.

If it gets over 5 seconds, it will be a problem. I don't know what I'll do with the circuit then.
.


Not sure where you are measuring temp, but I dont see a generator temp changing noticeably is less than a few minutes. The temp idea would be good to use to reduce the voltage across the cell until it cooled off though. the cell I am currently experimenting with (+nnnnn-) the current drops drastically when voltage drops from 14.4 down to 12.5VDC. (no PWM) Of course HHO output drops also.

ridelong
09-06-2008, 07:43 PM
Darn, I just can't get this circuit to behave. Screwed with it for about 2 hours and it is still screwey. Found out 1 thing, the softer hot melt won't seal. The hot melt sealing the first probe came loose and let electrolyte get into the temp sensor leads.

That was 1 problem, but not the only one. Built a new 10 mv per degree f probe. Seemed to be real stable. I replaced the 10 mv per degree c probe that had electrolyte in it. When I fired up the bottle the output went from 800 mv to 100 mv.

Will work on it in the morning.

ridelong
09-07-2008, 04:27 PM
Been in the basement all day. Finally got this sucker working. This thing works great.:D

One worry was the lag time, NO problem. The circuit naturally runs about 1428 Hz, perfect.

Been running an hour in the controller mode with controller setpoint at 151.9 deg F. During the test, temperature varied from 153.2 to 154.5, so the whole system error is less than 5 deg F.

During the test I aimed a 4 inch fan at the generator. The temperature went down to 153.2, and I watched the pulse width increase on the scope as the circuit adjusted for the difference. Current increased from 3.8 amps to 6.25.

I will add this circuit to my truck.

Still have to finish the heater portion that turns on a heating element when the gen gets below 38 F.

After that, I'll post the schematic and parts list.

Painless
09-07-2008, 04:59 PM
Awesome job!

Sounds like a great idea for controlling thermal runaway. Just out of interest, does the circuit have a way of setting the max amps the circuit will put through the cell?

ridelong
09-07-2008, 05:37 PM
Painless,

No there is no amp limiting.

What I intend to do is set the startup current with my electrolyte. It will be about twice the current that I normally run my generator.

The circuit will drive the gen hard until it gets to setpoint temperature, then it will go into feedback pwm to maintain the temp..

That way, the generator will put out max until setpoint, then will put out max it can without overheating the generator.

Will start on the winter circuit tomorrow.

overtaker
09-08-2008, 11:20 PM
Ridelong, Thanks for sharing your time and knowledge with us. It is much appreciated. :)

ridelong
09-12-2008, 06:54 PM
All,

Took a break, now I'm back.

Cleaned up the bench, fired up the temp circuit. The lm34 output was way high.

Took the probe out of the electrolyte. The hot melt keeping the electrolyte off the wiring in the ss tube fell off in my hand. Start tomorrow to find something to seal the end of the probe.

I'm thinking of posting only the temperature feedback pwm portion of this project. When I finish, will post the winter heater circuit with the temp pwm combo with relay switching between the circuits.

ridelong
09-13-2008, 06:16 PM
All,

Here is the link to the temperature feedback pwm.
http://www.mikecramer.com/images/temp-pwm800.jpg

This circuit oscillates about 1400 Hz.

Will post the system with winter circuit when I finish it.

B/M for this circuit:

All Electronics parts:

LM34 Cat# LM34DZ $2.50
1 uf Cat# RM105 $1.00/4

Digi-Key parts:

5k pot CT2264-ND $1.51
49.9k 49.9KXBK-ND .49/5
5.11K 5.11KXBK-ND .49/5
(2)25.5K 25.5KXBK-ND .49/5
4.99K 4.99KXBK-ND .49/5
200 OHM 200XBK-ND .49/5
10 VOLT ZEN 1N5327BTPMSCT-ND $3.90/10
FET IRL1404ZPBF-ND $3.67

resago
09-20-2008, 11:54 AM
so how hard would it be to add current limiting to the temp feedback.

that way, you set your max amps, then run them until heat becomes an issue. My alternator is weak and I would like to see a pwm that implements both.

ridelong
09-22-2008, 06:30 PM
resago,
It wouldn't be that hard to add current limiting, but it seems redundant. You can adjust the electrolyte to set the max amps. Then let it run until the gen reaches set point temp. Then it will adjust the pwm to hold the gen at that temp.

ridelong
09-22-2008, 06:36 PM
All,
Just finished testing the temperature feeedback with the winter circuit that turns on a heating element when the gen electrolyte gets below 39 deg F.

Works exactly as designed, turns on heating element at 38.8 deg, and off at around 39.4.

Now I have to find a heating device. Am looking at the USB cup heaters on EBAY. Anyone have a suggestion?

Will post the circuit and a picture of my unit soon.

BoyntonStu
09-22-2008, 10:15 PM
All,
Just finished testing the temperature feeedback with the winter circuit that turns on a heating element when the gen electrolyte gets below 39 deg F.

Works exactly as designed, turns on heating element at 38.8 deg, and off at around 39.4.

Now I have to find a heating device. Am looking at the USB cup heaters on EBAY. Anyone have a suggestion?

Will post the circuit and a picture of my unit soon.

Use the electrolyte as your heating element.

Pump up the Voltage by shorting out a few plates, and heating will result.

BoyntonStu

Q-Hack!
09-22-2008, 11:07 PM
Use the electrolyte as your heating element.

Pump up the Voltage by shorting out a few plates, and heating will result.

BoyntonStu

This would work as long as you aren't trying to start a frozen car in the morning.

ridelong
09-23-2008, 06:32 PM
BoyntonStu,
The operation of the winter circuit would be unattended, while the engine is off. I wouldn't want to generate any HHO without the engine running. I feel safer running a heating device on the outside surface of the gen.. Also need insulation of the gen.. Want to use the least power as possible.

BoyntonStu
09-24-2008, 07:55 AM
BoyntonStu,
The operation of the winter circuit would be unattended, while the engine is off. I wouldn't want to generate any HHO without the engine running. I feel safer running a heating device on the outside surface of the gen.. Also need insulation of the gen.. Want to use the least power as possible.

Hi!

What I suggest doing first is to place a small sample of your electrolyte in your freezer overnight.

If it is not frozen by morning, you don't have to worry.

If it freezes, there are many electrical heating options that will supply just enough heat to keep the electrolyte from freezing down to Arctic temperatures.

BTW Have you tried to apply voltage to frozen electrolyte just to see what happens?

BoyntonStu


P.S. If you supply less than 1.23 Volts per cell, no gas will be generated.

ridelong
09-24-2008, 05:44 PM
Hi BoyntonStu.

I am going to put a sample of electrolyte in the freezer overnight, just to confirm it will freeze.

I won't do any electrical experiments with frozen electrolyte. The reason is, I use glass jars. If I let the electrolyte freeze, thawing it will be the least of my worries.

I am going to order a 100 cup heating element, looks like a braided nichrome deal. It will draw about .25 amps at 12 volts. Will wrap it around the bottle, then insulate the bottle.

ridelong
09-26-2008, 06:51 AM
2.5 tsp KOH in 45 oz of distilled WILL freeze.

resago
09-26-2008, 08:41 AM
instead of a heating element. you could have the pwm sense the draw or temp like you already are.
I am assuming if it is frozen, the cell would act like a hard short. you could simply apply just an amp or two to the cell and let it be its own heater untill thawed.

ridelong
09-26-2008, 11:12 AM
resago,

I don't want any chance of HHO being generated while unattended (overnight, for example). The external heater removes all chances of that.

I can't let my gen freeze because it is glass.

resago
09-26-2008, 12:42 PM
how long do you think such a technique would take to thaw the cell?
I was thinking it could thaw itself in a few minutes, so no need to run if the engine is off.

I get the glass part though.

HHO King
09-26-2008, 06:39 PM
I am going to build one like i found here with the gauge and fan already assembled. http://www.extremehho.com .
I'm also going to install a temp gauge to monitor my cell.

ridelong
09-30-2008, 04:30 PM
All,

Here is a picture of the finished temperature feedback pwm. It is mounted in my truck and is running great.

The heater part is not done. I am waiting for the heating element from Ebay to arrive.

Am working on a readable pencil drawing. Should be done in a few days.

http://www.mikecramer.com/images/tempature.jpg

atfab
10-05-2008, 09:46 AM
Ridelong, Could you please give some more detail on the probe assembly. A pic or two would make things real clear. Thanks!

ridelong
10-06-2008, 06:32 PM
This might help.

The tube is .200 inch I.D. 316 stainless. The ss tube is press fit into a drilled out bulkhead water fitting. Both from Mcmaster Carr.

The sensor is an LM34, 10 mv/deg F output. Spec sheet at national semiconductor.

The sensor is sealed in the tube with Locktite epoxy putty from Lowes



www.mikecramer.com/images/probe1.jpg



www.mikecramer.com/images/probe2.jpg

ridelong
10-06-2008, 06:39 PM
Here is the final design that I am running in the truck.

The heater element I'm using is a 100 cup coffee heater wire rope. It draws 160 ma. at 12 volts.

I insulated the bottom and sides of my bottle with closed cell foam.


www.mikecramer.com/images/tempheater.jpg


--------------------------------------------------------------------------------

Here is the parts list for the temperature feedback pwm with the winter temperature circuit.

The listings are in three parts. First is the part (LM34). Second is the part number used to order the part (LM34DZ). The third part is the price
($2.50).

All Electronics company parts:

LM34 Cat# LM34DZ $2.50
(2) 1 uf Cat# RM105 $1.00/4



Digi-Key parts:

5k pot CT2264-ND $1.51
(2) 49.9k 49.9KXBK-ND .49/5
6.81K 6.81KXBK-ND .49/5
(2)25.5K 25.5KXBK-ND .49/5
(2)4.99K 4.99KXBK-ND .49/5
200 OHM 200XBK-ND .49/5
47.5K 47.5KXBK-ND .49/5
100K 100KXBK-ND .49/5
3.92K 3.92KXBK-ND .49/5
10 MEG 10MQBK-ND .27
10 VOLT ZEN 1N5327BTPMSCT-ND $3.90/10
(2)FET IRL1404ZPBF-ND $3.67
LM339 LM339NFS-ND .47



Hosfelt Electronics parts:

(2) inline fuse holder 43-181 .69
10 Ga. inline fuse holder 43-180 .79
12 volt 20 amp relay 45-689 $3.95
Relay base R95-115 $6.25
Dpdt switch 51-571 $4.95