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Painless
07-09-2008, 08:20 PM
Can anyone recommend somewhere to purchase a meter for measuring my HHO gas LPM rate?

Thanks in advance,

Russ.

dennis13030
07-09-2008, 08:33 PM
Check it out.

http://www.dwyer-inst.com/htdocs/flow/SeriesVFA-VFBPrice.cfm

Painless
07-09-2008, 08:38 PM
Great! Thanks, Dennis!

dennis13030
07-09-2008, 08:44 PM
Your welcome! The VFA($31.50) or VFB($43.25) series looks good.

If you use these, I recommend that during the time you are taking measurements that you do not use a bubbler at the same time. The bubbler tends to make the readings a bit unstable(bouncing).

dennis13030
07-09-2008, 08:46 PM
See my image below.

computerclinic
07-09-2008, 09:07 PM
Great link Dennis, I like the VFB-67-SS ($47) because it measures 1 to 20 LPM...I like the room to grow, though I really doubt I will ever produce much beyond 5 LPM in my wild dreams. I did see a youtube video with a fella running a 2 hp motor with 18 LPM...Motor was at idle, but solid...sounded like the timing was a bit off, too.

dennis13030
07-09-2008, 11:48 PM
Great link Dennis, I like the VFB-67-SS ($47) because it measures 1 to 20 LPM...I like the room to grow, though I really doubt I will ever produce much beyond 5 LPM in my wild dreams. I did see a youtube video with a fella running a 2 hp motor with 18 LPM...Motor was at idle, but solid...sounded like the timing was a bit off, too.

Was the 2 hp motor running ONLY HHO or a mix of something + HHO?

dennis13030
07-09-2008, 11:51 PM
Kinds related to this thread,

Does anyone know of a low cost device that measures gas flow AND can be read digitally by a PC??

computerclinic
07-10-2008, 08:13 AM
That sort of measuring would be HOT!!! Would be able to graph things out to visually see things going on with the numbers.

As for the 2 hp, it appeared that he was using straight HHO, 18 LPM of it. The Cells he was using were monsters and drawing something like 109 volts, dont know about how much amperage, but the bubbles looked like a hot tub, and the gas outlet hose sounded like a dentist office type of hose sound...LOL...He has a dry rag in the gas tank and had the hose plugged to the carb...

Jaxom
07-17-2008, 01:16 PM
I noticed that these meters are rated in LPM of air. Would the difference in weight between air and HHO affect the accuracy of these meters? On one hand it would seem that flow volume is flow volume regardless of what substance it is, but these meters are based on the airflow pushing the weight of the little plastic ball in there up, so maybe a change in the weight of the gas would change how much it takes to move the weight of the ball to a given height....

I dunno it's just something that crossed my mind.

dennis13030
07-17-2008, 02:44 PM
These flow meters are not calibrated for HHO. I am sure there is a difference but I think it would very, very small.

rzone
07-21-2008, 06:56 AM
These flow meters are not calibrated for HHO. I am sure there is a difference but I think it would very, very small.

For practical purpose the error is too small to make a difference (by coincidence if you add the atomic mass of the components you'll get close enough to content of air - O2, CO2, NOx etc). The thermal error is 5-6x time bigger than this.

For lab measuring purposes you can easily build a device similar to flow meter that you probably have in your car. It looks like this: a piece of Cro-Ni metal wire used in electrical heaters placed in a tube and powered by a constant current source. The voltage across the wire is directly proportional with lpm. Only thing you have to do is to tweak a little bit to find the linear part of the wire and calibrate it.You can also smash a light bulb and use the filament. The electronics within is trivial, and you can use a digital voltmeter to measure the output.
If you want to play with this I'll send you drawing details and principles

dennis13030
07-21-2008, 09:46 AM
For lab measuring purposes you can easily build a device similar to flow meter that you probably have in your car. It looks like this: a piece of Cro-Ni metal wire used in electrical heaters placed in a tube and powered by a constant current source. The voltage across the wire is directly proportional with lpm. Only thing you have to do is to tweak a little bit to find the linear part of the wire and calibrate it.You can also smash a light bulb and use the filament. The electronics within is trivial, and you can use a digital voltmeter to measure the output.
If you want to play with this I'll send you drawing details and principles

Please do send me the drawing details and principles.

JonDoh
08-01-2008, 07:50 PM
I found these for a few bucks:

http://www.tagamed.com/tagaliter.html

http://i41.photobucket.com/albums/e271/h2cars/Parts/flowmeter.jpg

Q-Hack!
08-05-2008, 01:38 AM
Kinds related to this thread,

Does anyone know of a low cost device that measures gas flow AND can be read digitally by a PC??

Not sure about low cost, but the Dwyer website you gave earlier does have these:

http://www.dwyer-inst.com/Products/Product.cfm?Group_ID=369

in case the link goes bad...

Series GFM Gas Mass Flow Meters combine a straight tube sensor with a restrictor flow element to provide high accuracy and repeatability. Flow rates are virtually unaffected by temperature and pressure variations. Actual gas flow is displayed in engineering units on a 3-1/2 digit, 90° tiltable LCD readout. Units can be used with Series GFT Flow Totalizer for applications requiring totalization. Series GFM includes a NIST traceable certificate.

The model GFM-2109 is rated for 0-5 LPM, is made of 316 SS, and has an RS-232 output for computer use.

And while this is exactly what we need... I am sure it cost a pretty penny. (they don't give a price)

Edit: Finally found the price... $947.00 Any of you rich people want to buy me one? :-)

dennis13030
08-05-2008, 09:21 AM
Not sure about low cost, but the Dwyer website you gave earlier does have these:

http://www.dwyer-inst.com/Products/Product.cfm?Group_ID=369

in case the link goes bad...

Series GFM Gas Mass Flow Meters combine a straight tube sensor with a restrictor flow element to provide high accuracy and repeatability. Flow rates are virtually unaffected by temperature and pressure variations. Actual gas flow is displayed in engineering units on a 3-1/2 digit, 90° tiltable LCD readout. Units can be used with Series GFT Flow Totalizer for applications requiring totalization. Series GFM includes a NIST traceable certificate.

The model GFM-2109 is rated for 0-5 LPM, is made of 316 SS, and has an RS-232 output for computer use.

And while this is exactly what we need... I am sure it cost a pretty penny. (they don't give a price)

Edit: Finally found the price... $947.00 Any of you rich people want to buy me one? :-)

Thank you very much! This is a key item in the automated testing and optimization of HHO electrolyzers.

JonDoh
08-05-2008, 09:33 AM
http://www.dwyer-inst.com/Products/Product.cfm?Group_ID=369

The model GFM-2109 is rated for 0-5 LPM, is made of 316 SS, and has an RS-232 output for computer use.

Finally found the price... $947.00 Any of you rich people want to buy me one? :-)

I second that!

Sweet unit!!

fly
08-09-2008, 07:33 PM
Well, Liter of air or Liter of HHO is still a liter of gas... So basically you have a volume per minute reading from the device.

My thoughts on this though are a little deeper:

Gas is easily compressed with pressure. Does those units mentioned on the links posted take pressure into account? if I have a 2 atm pressure in my line, I will basically have double the amount of molecules per volume than if I have 1 atm...

My question really is: Is there an AFFORDABLE Measuring instrument that can tell me the exact volume at 1 atm I am producing regardless of the pressure the gas is actually flowing through it (ie, it would detect the actual presssure, then figure out what teh volume would be at 1 atm or would have a pressure gage built in to let me know what is the pressure the gas flow was registered at?