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Thread: Just asking, DOES A PWM REALLY DO ANYTHING?

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  1. #1
    Gary Diamond Guest

    Just asking, DOES A PWM REALLY DO ANYTHING?

    I can't understand why anyone uses them, if you want to cut down current add more cells. i can't possible see how adj the freq. and pluse width duty cycle does anything Please prove me wrong.
    Gary diamond

  2. #2
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    Gary,

    A PWM comes into its own when you forgo the "two tsps of KOH for the amps I want to pull once its warmed up" and you use a maximum concentration electrolyte, use the PWM to control amp draw and increase the efficiency of your cell due to the lower resistance in it.

    I increased my MMW by a whole point with a PWM on my last cell.
    2006 Dodge Ram 4.7L - 16.5 mpg stock
    My thread Painless Experiment in HHO

  3. #3
    Gary Diamond Guest
    Quote Originally Posted by Painless View Post
    Gary,

    A PWM comes into its own when you forgo the "two tsps of KOH for the amps I want to pull once its warmed up" and you use a maximum concentration electrolyte, use the PWM to control amp draw and increase the efficiency of your cell due to the lower resistance in it.

    I increased my MMW by a whole point with a PWM on my last cell.
    If you say so, if the resistance is to low add another cell set, if your KOH is to strong cut it down, it just seems to me to be a fix for something broken, that should not be broken.

    Gary Diamond

  4. #4
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    You're still missing the point, Gary.

    Let me explain this a different way.

    If you use a 28% KOH solution, the resistance per cell gap will be X. If you use a much weaker solution, your resistance per cell gap will be Y.

    Y is a higher resistance than X, therefore, when Z amps are put through the two different setups, X will produce more HHO at the Z amps than the non-pwm setup, due to the lower resistance.

    Another benefit is cell warming. Let's say your target draw is 20 amps, you might add two tsps KOH to achieve this (for example). When your cell is cold it may draw 10 amps and move up to your 20 target as it warms. With a PWM you are running at your target amps from cold to hot. In other words, your required LPM is there from cold start.

    In a small output setup, a PWM may be overkill. But, in a setup where high output is required, the benefit of a) hitting your needed LPM out of the gate and b) achieving that LPM with less amp draw is welcomed.
    2006 Dodge Ram 4.7L - 16.5 mpg stock
    My thread Painless Experiment in HHO

  5. #5
    Gary Diamond Guest
    Ok I will agree with you if your set up starts to run away on heat, it would be good to limit current flow.
    -----------------------------------------------------------------------------------------------------------------------------
    I also feel if the HHO generator is designed correct, and placed in the front with cooling fins, there would not be any need to add a device to fix a problem that should not be there in the first place.

  6. #6
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    Quote Originally Posted by Gary Diamond View Post
    Ok I will agree with you if your set up starts to run away on heat, it would be good to limit current flow.
    -----------------------------------------------------------------------------------------------------------------------------
    I also feel if the HHO generator is designed correct, and placed in the front with cooling fins, there would not be any need to add a device to fix a problem that should not be there in the first place.
    I agree 100%, a PWM shouldn't be used as a band aid for bad cell design. It should be used for higher efficiency and consistant amp draw from startup to shutdown.
    2006 Dodge Ram 4.7L - 16.5 mpg stock
    My thread Painless Experiment in HHO

  7. #7
    SmartScarecrow Guest
    Quote Originally Posted by Gary Diamond View Post
    Ok I will agree with you if your set up starts to run away on heat, it would be good to limit current flow.
    -----------------------------------------------------------------------------------------------------------------------------
    I also feel if the HHO generator is designed correct, and placed in the front with cooling fins, there would not be any need to add a device to fix a problem that should not be there in the first place.

    I think your core question is, "will a PWM make more gas than without a PWM" ... the simple answer is no, it will not ...

    however, in operation, we find that these devices tend to ramp up production as they warm up and can if not controlled, pull more power than is available which causes problems and blown fuses and such ...

    you are correct that if your design is very precise, and you elyte concentration is very precise, you can control your device without the use of a PWM ... but doing this is a pain in the butt ... so the PWM gives average Joe an easy way to "dial in" a desired level of performance without having to be so precise with the other factors ...

    as a real world example, I am running small engine tests using a cheap little Chinese 1500w gas powered generator ... I am so close to getting the darn thing to self sustain that I decided I wanted to give it go even though I knew going in that I was a little shy of the mark ... having the PWM let me tweak my electrolyzer to a very precise setting so it not try to pull more juice than the little generator could put out but grabbed every bit of what it was capable of ... only with PWM could I control it that fine where I got every freakin' watt of power I could out of that little genny without popping its breakers ...

    did that help to explain it for you ?

  8. #8
    Quote Originally Posted by Gary Diamond View Post
    I can't understand why anyone uses them, if you want to cut down current add more cells. i can't possible see how adj the freq. and pluse width duty cycle does anything Please prove me wrong.
    Gary diamond
    To undertand more about a pwm you should consider reading this http://www.hhogaskitwizard.com/blog/what-is-a-hho-pwm/

  9. #9
    Join Date
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    Quote Originally Posted by Gary Diamond View Post
    I can't understand why anyone uses them, if you want to cut down current add more cells. i can't possible see how adj the freq. and pluse width duty cycle does anything Please prove me wrong.
    Gary diamond
    I find it interesting that most people simply use a PWM to control the current through an electrolyser in order to maintain the unit at a specific working temperature. In reality of course we want as much hydroxy produced as possible all of the time and so a PWM would not really be necessary in a correctly designed electrolyser.

    The PWM was not originally designed to simply control the current or the heating of an electrolyser, and in fact has an altogether different purpose, which stems from the work of Puharich and Meyer, then more recently by Dave Lawton, Ravi and others.

    The real idea behind using a PWM was to break down the water molecule by a method other than simple Faraday Electrolysis - but sadly this seems to have been lost to most people.
    Farrah

    It's what you learn after you think you know it all that really counts!

  10. #10
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    Lightbulb Pwm square wave frequency

    I am lead to believe that with 20,000hz-50,000hz square wave and an amplifier(music),placing both pos and neg output wires(speaker) In water with alu foil wrapped on each tip will split water! So if we could get our cells(plates) to resonate at that frequency sirely it would help with production and a pwm would become more effective in its use???,

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