Best Cell Performance - From Another Forum

[BoyntonStu]

Note* This was copied from another Forum.

I cannot vouch for it.

Compare 2.75 LPM @ 15 A to anything you have built.

That is 8 MMW!

FWIW

BoyntonStu

Reminder of the most efficient Cell we have!!‏

Summary
7 cell booster with 15 plates
6x12" plates 6"high,12"long.
316L 16 gauge
Quarter " stainless all thread
12 stainless steel nuts
10 stainless steel spring washers
4 quarter inch large stainless steel washers

6" pieces.
PVC material, 1" thick.
Box dimension are 14" long
9" high
8" deep

Jeff states the cell draws just under 3lpm at 15 amps. Starts out cold
at 7 amps after 12hours run just under 15 amps. Two days to assemble.
1day to build box and let glue dry. 1 day to do plates. What I suggest
is a series cell in the same box. +nnnnnn-nnnnnn+nnnnnn-nnnnnn+ with
6x12" plates would this be close to equal output of the Bob Boyce 61
plate box with 6x6" plates with brute force.

[overtaker]

I believe it. That is exactly in line with chapt. 10 page 38.

[1973dodger]

I must caution, I have seen many cells claiming high output at low amps, but if you read in the sidebar, over a hundred volts are being applied. The cell I am familiar with of Bob Boyce, uses a 110 volts to push the current thru his unit. Don't get me wrong, I hope it works, just use caution. High volts is something that is doable, just takes some bucks for toys needed up front.

1973dodger

[BoyntonStu]

I must caution, I have seen many cells claiming high output at low amps, but if you read in the sidebar, over a hundred volts are being applied. The cell I am familiar with of Bob Boyce, uses a 110 volts to push the current thru his unit. Don't get me wrong, I hope it works, just use caution. High volts is something that is doable, just takes some bucks for toys needed up front.

1973dodger

High volts up to 500 Watts is not only doable but cheap.

Buy any 500 Watt car inverter for less than $50 and you will have a modified sine wave 110 AC in your car.

Connect to $10 bridge rectifier and you will have 110 Vdc.

BoyntonStu

[1973dodger]

[QUOTE=BoyntonStu;12476]High volts up to 500 Watts is not only doable but cheap.

Buy any 500 Watt car inverter for less than $50 and you will have a modified sine wave 110 AC in your car.

They are not a 100% efficient, though. Some current is lost to heat, unless you bought one of those high dollar inverters at 93% efficiency. But I would be curious to hear of some test comparing high voltage low current to low voltage high current using the same watts for both. Say 100 dc volts at 2 amps compared to 10 volts at 20 amps, for example. Both would use the same wattage. Would the production be the same? Is it really excess voltage which causes heat or is it current. This type of test would settle that question for me once and for all. Does not a wire get hot, for instance, when too much current is being pushed thru it and is not a wire cool to the touch when high voltage is applied at low current? Sure, all this relates to resistance, but is there not less resistance when higher voltage is applied?

1973dodger

[sp1r0]

High volts up to 500 Watts is not only doable but cheap.

Buy any 500 Watt car inverter for less than $50 and you will have a modified sine wave 110 AC in your car.

Connect to $10 bridge rectifier and you will have 110 Vdc.

BoyntonStu

not to be too picky but actually 110VACx√2 =155VDC

[Jaxom]

not to be too picky but actually 110VACx√2 =155VDC

Not quite how it works. You'd actually end up with about 77v RMS. Diodes don't generate voltage, they just direct current flow.

If you run 240vAC through a diode bridge and output filter you get 155vDC.

[BoyntonStu]

not to be too picky but actually 110VACx√2 =155VDC

Spiro,

Thanks,

A cheap inverter however does not make pure 110 VAC.

http://www.youtube.com/watch?v=VN6NP9X5Q9c.

I would guess a lower VDC from a car inverter.

In both cases add a few plates for 2 VDC/cell. (pun intended)

BoyntonStu

[donnylynn]

Jaxom
Sp1r0 is correct. its 155 DC
read this
http://www.samtec.com/technical_library/reference/articles/pdfs/VOLTAGE_POWER_Ratings_102007.pdf

[BoyntonStu]

Jaxom
Sp1r0 is correct. its 155 DC
read this
http://www.samtec.com/technical_library/reference/articles/pdfs/VOLTAGE_POWER_Ratings_102007.pdf

Actually, I disagree.

I believe that both of you are confusing Voltage RATING with Voltage.

Read your link again.

For 110 VAC the RATING for DC would be 155 VDC.

Look at the TouTube video link above.

Do you believe him and/or his meter?

I hope that this helps,

BoyntonStu

[sp1r0]

Not quite how it works. You'd actually end up with about 77v RMS. Diodes don't generate voltage, they just direct current flow.

If you run 240vAC through a diode bridge and output filter you get 155vDC.

How do you figure that? I've built many DC power supplies. Using a 9VAC transformer through a full wave rectifier (bridge) and filter cap's, you get 12.7VDC. Using a 12VAC transformer with same setup I got 17VDC.

[donnylynn]

I didnt see a meter in the video so not sure what you are referring to.
110VAC as generally referred to is in the form of a sine wave centered on zero volts and is an RMS voltage. The peak value of the sine wave is 110 times the square root of 2. (RMS is an abbreviation for Root Mean Square.) Running this sine wave thru a full wave bridge rectifier will essentially fold the lower half of the sine wave upwards to result in a series of rounded pulses. Puta large electrolytic capacitor on this and you will end up with about 155VDC with some AC ripple riding on top of it. When you put a load on this output it will drop somewhat and the ripple will get worse.

I will cede the point that an inverter output is not a "true" sine wave. They "chop" the DC to create a pulsed DC that is then run thru a transformer to increase the voltage. This output contains a lot of harmonic frequencies so it will not be a pure sine wave.

[sp1r0]

I guess I am "old school". It seems the more I learn, the more we have to re-learn all over again. Switching power supplies and PWM take a simple formula and put it through a blender. I've never rectified or looked at the output of an inverter on a scope. Is it 120VAC or not? I would figure the more harmonics, the higher DC Amps, after the full-wave rectifier, because it's pulsing that cap closer to DC (the top of the sin wave).

[BoyntonStu]

I didnt see a meter in the video so not sure what you are referring to.
110VAC as generally referred to is in the form of a sine wave centered on zero volts and is an RMS voltage. The peak value of the sine wave is 110 times the square root of 2. (RMS is an abbreviation for Root Mean Square.) Running this sine wave thru a full wave bridge rectifier will essentially fold the lower half of the sine wave upwards to result in a series of rounded pulses. Puta large electrolytic capacitor on this and you will end up with about 155VDC with some AC ripple riding on top of it. When you put a load on this output it will drop somewhat and the ripple will get worse.

I will cede the point that an inverter output is not a "true" sine wave. They "chop" the DC to create a pulsed DC that is then run thru a transformer to increase the voltage. This output contains a lot of harmonic frequencies so it will not be a pure sine wave.

No capacitor: What volts dc from 110 VAC?

BoyntonStu

[sp1r0]

DC RMS (avg 60Hz US 50Hz EU). You are riding the sine wave without Cap's

[BoyntonStu]

DC RMS (avg 60Hz US 50Hz EU). You are riding the sine wave without Cap's

That is what I said in my first post.

BoyntonStu

[BoyntonStu]

How do you figure that? I've built many DC power supplies. Using a 9VAC transformer through a full wave rectifier (bridge) and filter cap's, you get 12.7VDC. Using a 12VAC transformer with same setup I got 17VDC.

Did you measure the dc without caps?

BoyntonStu

[sp1r0]

No, I've always used filter cap's. Not for HHO production. Power supplies for digital IC's or MOSFET's, audio amps require a steady DC voltage. The sin wave may be useful for HHO production is some way, who knows. I didn't mean to start this long discussionon on DC rectifying, it's usually pretty simple and straightforward.