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astrocady
12-13-2009, 03:32 PM
I have a set of S&K dry cells that don't work worth a crap. I measured only .4 LPM from both cells, using the bottle-in-water method. That's only .2LMP each -- far from the .8 to 1.0 lpm per cell I expected. The electrolyte gets hot with lots of foam. This was at 13.5v and 25 amps with a duty cycle of 80% through a PWM. Electrolyte was potassium carbonate, one gram to one ounce or water.

The cell arrangement was...
n-nnnn+n and the left hand 3 n plates are electrically bonded to each other and the right hand 6n plates are electrically bonded to each other.

From reading this forum, I learned that having 5 neutral plates between + and - is better than 4 neutrals.

I have no idea what the neutrals on each end do -- any thoughts?

Anyway, I took the cells apart and swapped the two end plates so I now have n-nnnnn+. I didn't know what to do about electrically bonding the neutral plates, as I haven't read anything here about that, so I left them as they were -- the left 3 are electrically connected to one another and the right 3 are electrically connected to one another.

Also after reading this forum, I decided my electrolyte concentration may be too weak, so I increased it to 2 grams per ounce of water.

I just completed my first tests. My results were .67 lpm for the two cells, so I saw an increase, but not as much as I'd hoped. This test was also at 13.5v and 25 amps, but the duty cycle of the PWM had reduced to 50% (from the higher electrolyte concentration I presume). I have not run this setup long enough to know yet about heat or foam.

Since I hadn't read anything about electrically connecting the neutral plates, I started wondering about this. It was easy to jumper from the left bank to the right bank, so I tried this, making all the neutral plates electricaly connected. This REDUCED the output to .58 lpm. So now I'm wondering if they should be connected at all?

What should I do?

Thanks,
AstroCady

Helz_McFugly
12-13-2009, 06:45 PM
I have no idea what the neutrals on each end do
pretty sure they do nothing. Iv never seen that before

how big are the plates?
link to where you got it?
got any pictures of it?

astrocady
12-13-2009, 09:02 PM
The cell plates are round, but I didn't measure the inside of the gasket when I had them appart. I think the inside measurement is about 5, maybe 5.5 inches in diameter?? I didn't take any pix of it apart.

Here is a link to a page on S&K's website that shows the cells I have. http://www.skhhofuelsystems.com/photo3.html

The cells were new when I get them, but I got them through a series of trades.

What about electically connecting the neutral plates???

Helz_McFugly
12-14-2009, 07:45 AM
I would take them apart and make them -nnnnnn+
at 13.8 vdc. that would be 1.97vdc per cell. 7 cell stacks are very efficient. we have been testing up to 9 cell stack and getting very good results. follow that link in my signature

astrocady
12-14-2009, 06:32 PM
Thanks for your help, Helz. I measured the inside of the gasket and it is 4.5". So i my math is right, that would be a little over 15 sqaure inches. I've read somewhere that the current should be .5 amps per square in. So that would be 7.5 amps. Is that per plate or for the entire cell?? I turned my amps down from 25 to 15 for my 2 cell system tonight and the output seemed to really drop off (only visualy, didn't do measurement). Then again, how much of the "gas" I was seeing and measuring at 25 amps was realy HHO and how much was steam? Maybe i'm really producing the same amount of HHO at 15 amps as I was at 25, but with a lot less steam so it looks like less bubbles???

Still confused about whether there should be jumpers attached to the neutral plates to electrically connect them to one another.

lhazleton
12-15-2009, 12:19 PM
The amp draw would be for the entire reactor. Connecting the neutrals in any way is just rediculous. The 'neutral' plates, as everyone calls them, are actually 'bi-polar', and can't be connected in any way. Your reactor's extra N plates are a mistery. They couldn't serve any purpose at all. Like Helz said, reconfigure it to +NNNNNN-.

astrocady
12-15-2009, 06:22 PM
Thanks lhazleton. That what I figured. I reconfigured them last night and will reinstall this weekend. Will post my results.

oicu812
12-16-2009, 01:26 AM
The amp draw would be for the entire reactor. Connecting the neutrals in any way is just rediculous. The 'neutral' plates, as everyone calls them, are actually 'bi-polar', and can't be connected in any way. Your reactor's extra N plates are a mistery. They couldn't serve any purpose at all. Like Helz said, reconfigure it to +NNNNNN-.how true! I wish we could get away from calling them neutral plates and switch to bi-polar plates

lhazleton
12-17-2009, 06:11 PM
I've tried that configuration and when I submerfge them in a bath of solution the entire bottle would turn in a white cloud. but when I enclosed them in a dry cell set up and run the same solution mix the output barely keep my torch alive and the terminals, they get hot fast.

What is your KOH percentage? For a dry cell Reactor to perform correctly, you need at least 5 Bi-Polar plates per cell and 25-28% KOH e/lyte.

astrocady
12-19-2009, 03:50 PM
UPDATE

I rebuilt my cells. They are now +nnnnnn- with the neutral 9or bi-polar) plate not connect to anything.

When I reinstalled them into my car and fired it up, I found out why S&K had the neutral plates connected to one another. Because the cell didn't work otherwise. The LCD display for my PWM just said "no load detected, check connections." Finally, out of desparation, I hooked some jumpers between the neutral plates and low and behold they started pumping. If I unhooked the jumpers, the production stopped and the amps dropped to zero.

I played around with the jumpers some, and I found that when I start with the neutrals all connected together, and with my constant current PWM set at 26 amps (13 amps per cell), my duty cycle was about 50%. As I unhooked jumpers, the duty cycle would increase until it reached the maximum (I had that set at 85%), then the amps would start to fall off until they finally reached zero.

So I began to wonder if my electrolyte might not have enough conductivity. I am using patasium carbonate. At first I was using 1 gram per liquid ounce of water as recommended. But about a month ago I increased the strength because my duty cycle was so high (75%) to about 2 grams per liquid ounce.

Today I increased it to 3 grams per liquid ounce, and after doing that my duty cycle, with all neutrals jumpered, droped to 42% (still at 26 amps). With all the jumpers removed, it was at its maximum duty cycle of 85% with amps at 4 and bubble of HHO every once in a while.

I have some KOH, and had planned on switching to it, but deciced not to because it is so much more corrosive. My system in installed in the trunk of my car, and everytime I change cells some electrolyte always leaks. I'm afraid the KOH would rust out the trunk in no time. Of course, if the cells worked properly I'd have no reason to unhook them so I shouldn't have t o worry about spills. Still... it seems like pretty nasty stuff.

what do y'all think?

astrocady
12-20-2009, 11:39 AM
Sunday update.

Changed electrolyte to KOH. 2 lbs of 90% flakes to about 2/3 gallon of distilled water, which according to the chart should give me 28%

No real change. When I unhook the jumpers I still get only about 10 amps at 85% duty cycle and few bubbles. With all the jumpers in place I get 26 amps at 37% duty cycle, but only about .4 lpm per cell when checked with bottle method. I'm also seeing some vapors coming out the hose, even though the cells and electrolyte feel cool.

These cells are square with the inside of the gasket measuring 4.75 inches. There are a total of 8 316 stainless plates arranged +nnnnnn-

These cells were both brand new, and the stainless was very clean, but very slick. I've currently got them hooked to an external power supply bubbling away. I've heard that it sometimes can take several hours for the plates to "burn in" before they really start producing. I hope this is true, but I'm really starting to get discouraged.

Any help greatly appreciated
Steve

H2OPWR
12-21-2009, 12:35 AM
Sunday update.

Changed electrolyte to KOH. 2 lbs of 90% flakes to about 2/3 gallon of distilled water, which according to the chart should give me 28%

No real change. When I unhook the jumpers I still get only about 10 amps at 85% duty cycle and few bubbles. With all the jumpers in place I get 26 amps at 37% duty cycle, but only about .4 lpm per cell when checked with bottle method. I'm also seeing some vapors coming out the hose, even though the cells and electrolyte feel cool.

These cells are square with the inside of the gasket measuring 4.75 inches. There are a total of 8 316 stainless plates arranged +nnnnnn-

These cells were both brand new, and the stainless was very clean, but very slick. I've currently got them hooked to an external power supply bubbling away. I've heard that it sometimes can take several hours for the plates to "burn in" before they really start producing. I hope this is true, but I'm really starting to get discouraged.

Any help greatly appreciated
Steve

Check the voltage at your cell and devide it by 7. If you are much below 2.3 volts than you have too many neutral plates. 28% KOH in that cell should be drawing way more than 10 amps. With your cell in your trunk I would bet that you are at or close to 13 volts. 6 Neutral plates is too many for that voltage. My guess is that if you go to 5 neutral plates with 28% KOH your amp draw and production will jump.

Larry

astrocady
12-21-2009, 04:42 PM
Thanks for your advice, Larry. I did check the voltage. With the pwm set for 100% duty cycle, my voltage from terminal to terminal was 13.2 volts. From terminal to 1st plate was 1.97 volts. I thought 2 volts was the target? Do you think .3 volts would make that much difference?

H2OPWR
12-21-2009, 05:17 PM
Thanks for your advice, Larry. I did check the voltage. With the pwm set for 100% duty cycle, my voltage from terminal to terminal was 13.2 volts. From terminal to 1st plate was 1.97 volts. I thought 2 volts was the target? Do you think .3 volts would make that much difference?

Yes, It will make tons of difference in amp draw and production especially with a stainless cell. I have never heard of anyone making a 6 N cell work on automotive voltage.

Larry

H2OPWR
12-22-2009, 10:40 AM
I've been reading a lot of the thread to get my feet wet. I read in this thread about the percentage of KOH, 28% and a chart was mentioned. How does one calculate the KOH percentage you are using and where can I get the chart they speak of.

Since I am new at this I am using a teaspoon to measure the amount I was mixing with distilled water. Currently I am using a tablespoon per 1/2 gl. for two cell with three 2"X6" SS plates with 1/4" seperation. Have not tested for ouput aside from hooking up a torch and produce an 1" long flame.

sorry If I am stealing the thread.

It is really quite simple. First get a decent digital kitchen scale. Then weigh the water you want to use. For this calculation lets say that you have 4 pounds of water. So 4 pounds of water equals 64 ounces by weight.

Take the 64 and devide by 72. You then have .889. Multiply that .889 X 100. You get 88.9.

You are shooting for 88.9 ounces of total solution. Take the 88.9 ounces and subtract the origional 64 ounces of water. You now need to add 24.9 ounces of KOH by weight. You now have a solution of 28% KOH by weight.

Larry

H2OPWR
12-22-2009, 04:16 PM
Thanks for the education Larry. I am going to clean my system and start out with this mix.

Be careful with that strong a mix. First it is VERY caustic and will cause severe chemical burns. Second if your cell is vulnerable to much current leakage then your effeciency may go down instead of up.

Larry

astrocady
12-23-2009, 02:36 PM
Here is a link to a web page that has tons of information about KOH, including a chart that shows you exactly how much of 90% grade KOH to add to a gallon of distilled water to reach certain percentages. It also give you the specific gravity of varying concentrations so you can check your electrolyte with a battery hydrometer to verify your concentration.

http://www.ashtachemicals.com/products/kohchem.htm