Senior Member
Is there any sort of "HHO Dictionary" resource out there? A compendeum of agreed upon terms? I think one of the biggest hinderances in this community is one person using a term, and another person taking a totally different meaning of it.
I'm talking about something SO basic as "HHO" or "Brown's Gas". Do we all agree that these are the same thing, and that they are just short hand for "a stochiometric ratio of 2H2 and O2 molecules in gas form"?
Junior Member
what do people mean by pwm is another question I have.
Senior Member
PWM is an electrical engineering term(usually). It means "Pulse Width Modulation". PWM is usually applied to a load by "modulating" a signal with an On and Off series of pulses. Think of it as someone turning your light switch off and on REALLY fast(like 1,000 times per second). Your eyes can't pick up the flickering of the light because it is switching on and off way too fast. However, your eyes CAN pick up the amount of time that the light is turned on. There are two properties of a PWM signal - frequency, and Duty Cycle. Frequency is the number of times, per second, that the signal goes off, then on, then back off. Duty Cycle is the PERCENTAGE of "ON" time, to the total cycle time. For example, if the light switch is being turned on and off 1,000 times per second, and was only on for 250 microseconds for each cycle, then the cycle "period" would be 1,000 micro seconds(1millisecond). The duty cycle would be 25%(250microseconds / 1,000 microseconds). The frequency, of course, is 1kHz.
The reason PWM is used in many applications, is to adjust the output power/signal level, without suffering from linear limiting(like a resistor to limit current). Let's say that we directly connect a 12V battery to an HHO cell. If we measured the current, let's say that the cell is drawing a nice even 10 Amps. The power that the cell consumes would then be 120W(12V * 10A). Now, let's use PWM to limit the current. We will adjust the PWM controller so that it is operating at 1kHz, and it is on a 50% duty cycle(on for 500uSeconds, off for 500uSeconds). Now, the current is still flowing at a rate of 10A, but then it stops for an equal amount of time, then turns on again, then off, then on, etc.... The AVERAGE current(and RMS in this case) is now only 5A through the cell, or 60W being drawn from the battery. If you, instead, put a large resistor in series with the cell to limit the current to 5A, then the cell would still consume 60W, but you would also be wasting 60W with the resistor through "heat".
In other words... PWM is used to supply power to a load, without over driving the load with TOO much current, or wasting power on a limiting resistor. PWM also has other uses, such as creating sound waves, but that is an entirely different subject.
Senior Member
I totally agree, Philldpapill. I think part of the problem is that it is easier to simply go with the flow than it is to try and correct people all the time with a long winded explanation without coming off as a jackass.Originally Posted by Philldpapill
Maybe, it's that many people think we are innovators in a newly created field when we are actually just tinkering around in a well established scientific field known as electrochemistry...I don't know. Don't get me wrong. I think a lot of great research is performed in the garages and workshops around the globe by smart laymen...I'm just sayin'...
One of my pet peeves is the misleading pseudo term "Neutral Plates" while the proper name for them is "Bipolar Plates" and the common term, in the scientific community, for the actual electrodes (cathodes and anodes) is "Monopolar Plates".
In any event, there is an online electrochemistry dictionary as well as an online electrochemistry encyclopedia that are easily found with a google search.
Nick
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