Need Help..Controling DC Current

[Deleted]

Hello all, I've just joined this site today.. I've read a number of posting.. and have to laugh.. there seems to be a number of us that have forgotten our long ago learned electronics.. it ratteling in the back of my head.. but sometimes hard to retrieve..

But I see there are others who are obviously still on top of there game... and I need their help...


I want to build a power controller that will deliver a constant dc current to a varing resistive load. The current can raise as the resistance decreases to a predetermined value.. and then is held there...

It needs to work off a car battery/alternator (12 Vdc) and deliver upto 25 amps.. but be adjustable for lower current levels.. maybe 10 amps and higher.. maybe a selector switch system with 5 amp intervals... or scaled with a variable resistor..

Somehow you have to sence the current, and adjust the incoming voltage... but how?

Thanks to anyone that responds..

RobbRyder..

[Gary Lecomte]

Another guy trying to run his car on Hydrogen.

possibly a thermistor to sense current and control a PWM circuit.

[Deleted]

I am ...one of those guys.. I'm trying to find the best solutions I can to increasing gas milage.

Once I have it... I'll teach everyone I can find how to build one.. I'll go to every church in town...(theres a lot of them)..tell the priest, pastor, elder who ever.. what I have to offer. if he can arrange a work shop.. I'll show 5 - 10 mechanically inclined people.. auto mechanics, machinst.. electroinc guys.. whom ever they have, that is willing to show others..

Then we build.. a simple, yet effective system... designed for ease of construction and operation.. after a couple of sessions.. the instructor corp will have grown 1000%

all I ask... is they get there sister churches around the area involved... and they theirs... and go teach them... and increase the instructor corp... by 1000% again..

Then I'll hit the boy scouts, Legion, any one any where how is fed up.... and willing to do their part to say F... big oil..

So yes, I need a circuit to control DC current... with no operartor input, a value that can be designed into a circuit... If I have a circuit board, and parts.. I can teach anyone how to solder then in..... I just need the dang board.. the rest is PVC and Stainless steel...

and I'll take any suggestions on design.... or pratical matters... (such as how do you use it in the Norht in the winter..)... How do you use it on a Diesel... ? Anything anyone might want to contribute..

I see we have a retired circuit designer to thank for this site, and also a former NASA engineer... you guys can do it... figure it out..


Me, I'm just a conduit for the info... a natural teacher... I spent 10 years in the Army as an NCO, and 3 of those instructing maintenance and repair of automatic process control systems..

Until a few years ago, I had a thriving business rebuilding the finest printing presses made in the world... 12 employees.. with a world wide reputation as an honest dealer in an exacting field..

Then it all disappeard.. and with the help of hindsight it's easy to see how it happened... the wealth of the middle class has been plundered by the high and mighty.. Gas at $4.00, Milk almost as much...

The only way it will change is from the bottom up.. I'll do my part if you can do yours.... Cause, the guys on top... still want more..

If you can't help no problem... send me your email address and when I have it figured out... I'll send you the plans with pictures and explanations.... and keep in contact with you. till you have it working... (as long as you show 5 other people how to do it)..

If you can help, and don't... then you are just part of the problem.. and I want solutions... As we say in the Army... Lead.... Follow, or the the F... out of the way...

RobbRyder...

[rmeyn]

I have an open mind on most subjects. Circuitry, as you have requested, most surely exists. But much larger questions present themselves. If you are indeed attempting to run a car wholely, or in part , from hydrogen gas hydrolyzed from water, the real question is where are the thermodynamic computions which show you will get greater energy out than energy put in? It takes a great deal of energy to separate water into hydrogen and oxygen molecules. The resulting hydrogen gas, when combusted, produces little energy for the space it takes up.
One severe limitation of hydrogen fueled cars is the very limited mileage range.
Now if you are planning some kind of water injection method to improve gas mileage, that might be a possibilty. I heard of water injection over the years as feasible, but I don't really know the mechanics of it.
That being said, I would like to see the thermodynamic calculations.
rmeyn

[Gary Lecomte]

Hi RobbRyder, You will NEVER be able to run a car on Water by using Electrolysis.

You Can Assist the gasoline in adding hydrogen by electrolysis, But what it really does is just run the Motor LEAN. While this does give extra mileage, in many cases it can also Damage the motor.

Definately NOT something I would do to my vehicle.

Now IF you want to discuss this better in Person,
Email me your Phone Number as I can call you for Free.

Gary at: [e-mail]

[Deleted]

Hi Gary, thanks for the input.. and I'll take you up on your offer.. and email you shorty...

But this part is for anyone.. I have no plans what so ever, to attempt to run a hydrogen only car.. Only hydrogen assist.. with the necessary extras to make it worth while and also protect the engine..

The real point is.... what if it only saves 25% even 15%.. it's worth the trouble... then take that knowledge, break it in to easy to understand steps... and teach others.. What can be wrong with that?

Personally, I have a great understanding of control loops.. relay logic, digital logic, ladder diargrams and and..and...and...

I pretty much have it all figured out as a system.. except some of the electronics..

What I can't do.... (anymore)... is design circuits.. So anyone that has a circuit diagram, schematic for a DC Current control system... (15 - 25 Amp)... from a 12 car battery... I'd like to see it, if your willing to share it..

RobbRyder...

[Deleted]

Robby,
Right know in America most people are unwilling even if they have the resources to afford. They certainly are not going to spend time and effort to gather material, build without machine tools, fabricate electrical controls or convert vehicle battery relocations , finally install and then maintain a boost system to possibly only get 15% return.
They might as well get a second job and continue to forfeit the spare mulla right back into the hands of the mullah Saudis and Texas oil Barons. Also the derivatives swindlers.
American beer drinking good ol’ boys just don’t friggin care. Your an anomaly as I am.

I suppose by now Gary and yourself may have conversed. Gary you deserve an award, that’s a nice web site you have built.
After some considerable effort in researching the Hydrogen assist phenomena, I have found the sales side to be misleading; I found weird mystical stuff about Joe cells, the hydrostar information $5 slam dunk or what? 1.7LPM of hydroxy gas using a 20 amps smack booster for around $200 yeah sure. I finally came upon Gary’s site. He explains his circuits and experiments easy enough. We might just accept most of us will never be in a position to get something for nothing. Well I don’t think you were actually saying that was your intent, but this hydrogen subject seems to lean toward that notion. Tap water? baking soda? Seems too easy. You need a certain amount of current to satisfy the conversion process. To much and your wasting vehicle horsepower to attain cheap horsepower???. Physics, chemistry not being my better discipline, I suppose any number of ideal wrongs and that current becomes the source for heat. The best cell design seems to be stumping most. I have yet to build one. I have all the stainless steel one would ever want. Now I’m starting to really dig deep and I’m back on the fence. Cell design seems critical. Then you need the perfect concentrate of electrolyte, how does that stay at the ideal concentration over time? Throw it away frequently? Wasted money! Then winter comes along, A small block heater plugged in at night? Energy costly! What about the need for an Electronic Fuel Injector Enhancer (EFIE). I understand that the Hydrogen assist booster mandates that you cut in and convert the signal coming from the oxygen sensor(s) back to the computer. How often is manipulation adjustment necessary? This “fake out” of the varying 0.0-1.0 VDC sinusoidal wave that may represent in a combined sense, gas/break pedal use-misuse, injector performance, chamber efficiency, gas molecule atomization i.e. chemical additives designed for thorough break apart efficiency and vehicle temp, A few 1’s and 0’s get satisfied and the firmware does its thing dancing with stepper motors, actuators and Top Dead Center timing manipulations. Running lean means running cold, I don’t know how that could damage the motor unless the long-term incomplete combustion creates efficiency reducing deposits or carbon damaging residue or clogging of the Cat. Converter. But the Hydrogen is supposed to allow this to burn so much cleaner, so there’s a possible balance. So maybe putting in a hotter (if available!!!) temperature thermostat. Then you get into hot weather and this may be fighting against better intentions. The heat creates expansion and expansion is resistance and drag. Those darn computer firmware loops sure seems to eliminate every shade tree mechanic.

I ask should I also bother? I’m thinking about getting a horse. And brewing my own beer. Maybe I’ll barter it cheap enough to feed my kids from my neighbors chemical induced garden.
Robby, maybe just consider purchasing the Electronic Fuel Injector Enhancer (EFIE) electronics circuits to tell the computer things are rich and just maybe realize a 3 -4 MPG gain when it runs lean, without any hydrogen assist and without reengineering the inefficiencies designed under your hood. I think that’s another topic “computer reprogramming for maximum efficiencies” that aught to bring out the code crunching wizards!

Like Gary says, experiment and Enjoy! I wish I could afford it! Another topic concerning the joys and opportunities of one generation compared to another.

Verm

[Deleted]

May 18, 2008 16:41:51 GMT -8 @robbryder said:

What I can't do.... (anymore)... is design circuits..
So anyone that has a circuit diagram, schematic for a DC Current control system... (15 - 25 Amp)
... from a 12 car battery... I'd like to see it, if your willing to share it..

RobbRyder...

This not very difficult to do.
Not many parts needed.

- 1 strong power transistor - MOSFET is probably best here
- 1 small controlling circuit using 1-2 smaller transistors
- The controller will be adjustable to set any Constant Current you need
- This Current will flow through the Power MOSFET, from ~12 VDC
- If your battery have Voltage 11.0 - 15.7 Volt does not matter, same Current always

If you wish I will make one such circuit for you.
It is a very simple thing for meto do.
---------------------

Please, my friend.
What I need are as many details as you can give me.

Your idea how it should work.

.. Current wanted: for example adjust from 10 - 25 Ampere, with one potentiometer.
Then I will test this circuit in my Electronics Simulation software.
So works perfect.

I also want to know what will be MAX Voltage DC of your car battery.
Maybe 15 - 16 Volt?

[Gary Lecomte]

Lineup, I would like to see your proposed: "Constant Current Controller" Idea. And a Constant Current circuit should Not affected by input voltage.
(As long as it doesn't Exceed the voltages of the individual parts.)

And contrary to what some people believe, PWM does Not control Current.
It just controls a Duty cycle.

This "Constant Current" is Not so easy on a cell that changes resistance with temperature and with currents exceeding 15 amps.

However There is a Current Limited PWM Control on my site that does Pretty Good.

Your Thoughts, Lineup?

Gary

Jul 27, 2008 19:14:12 GMT -8 @lineup said:

This not very difficult to do.
Not many parts needed.

- 1 strong power transistor - MOSFET is probably best here
- 1 small controlling circuit using 1-2 smaller transistors
- The controller will be adjustable to set any Constant Current you need
- This Current will flow through the Power MOSFET, from ~12 VDC
- If your battery have Voltage 11.0 - 15.7 Volt does not matter, same Current always

If you wish I will make one such circuit for you.
It is a very simple thing for meto do.
---------------------

Please, my friend.
What I need are as many details as you can give me.

Your idea how it should work.

.. Current wanted: for example adjust from 10 - 25 Ampere, with one potentiometer.
Then I will test this circuit in my Electronics Simulation software.
So works perfect.

I also want to know what will be MAX Voltage DC of your car battery.
Maybe 15 - 16 Volt?

[Deleted]

PWM ( pulse width modulation )
is a good way to control average current.

Now, it all depends on what requirements the topic poster have.

PWM can have less power losses, than a simple constant current source.
On the other hand, a CCS is much more simple to build.