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Uwee
08-07-2008, 09:31 PM
I have been working on this HHO thing for a few weeks now and have been taking notes the whole way. I like to think I have learned a few useful things but still many things I dont know.

Currently I am using a 6 plate cell to test as many things as I can and collect all the data I can. When I get the pictures off this memory card I will post them but for now I am using those light socket covers from Lowes but flattened and connected together. The surface area (as far as I know) is currently 27sq inches of reactive surface. The power supply we are using is a ATX power supply to test a few different voltages.

It produces:
Orange Wire: 3.3v/15a
Red Wire: 5.15v/17a
Yellow Wire: 12v/17a

Rated to put out a max of 25a per line.

My question is once we connect on a 12v line even with tap water drawing 6a total in parallel it overheats (the wires between the power supply and the cell) within 3 minutes. When we ran a test with baking soda it was overheating MUCH faster so we only ran short 100ml test fills. It was getting to untouchable within 30-40 seconds.

When running a 100ml fill test the readings were:
11.88v/18.2a/216watts
100ml in 24 seconds
ml per sec: 4.58 / liters per hour: 16.5


Why are the wires getting hot? (sorry that was long winded. I just wanted to provide all the info that could be needed :))

Uwee, Thanks ahead of time for any info//

Painless
08-07-2008, 09:34 PM
My first question would be what gauge of wire are you using? According to your post, your PSU's 12v line runs at up to 17amps, you would be best off with 12 or 10 gauge wire for this.

If you were running at that maximum of 25amps, you would definitely be safer with the 10 gauge.

Uwee
08-07-2008, 09:39 PM
I was thinking the same thing. But if its related it also heated up at only 4.6a on a different power supply (thats why i changed to this one...). I dont know how to measure the gauge of a wire but they are wires from some psu molex connectors so I think they would be the same thickness right?

Painless
08-07-2008, 09:48 PM
If you're saying that a different PSU had the heating issues at a lower amperage then I would also suspect that perhaps you are overloading the PSU and the heat is tranferring to the wires? Do you have a meter for verifying the amount of amps that is passing through the wires? You might be exceeding the PSU's capacity if there is a short in your connections or if you are using too much catalyst in your electrolyte.

An overheating PSU would probably be cut off by it's thermal fuse in this case, but you can never be too sure.

It is also worth considering that whilst the PSU can put out a max of 25 amps, this is only a temporary ability, i.e. you can only sustain the 12v at 17amps during consistant usage.

Once again, we really need to know how much current you are really drawing.

justaguy
08-07-2008, 09:48 PM
It sounds like your plates might be shorting. How close are the plates?

Uwee
08-07-2008, 10:06 PM
I just measured 1/4 inch on all but one...

I have a digital amp meter that I was getting 18.2a from one side of the pc power connector and the other side on the positive.

Painless
08-07-2008, 10:15 PM
Seems like you're well within the rating of your PSU, hard to tell about the wire though just by thickness...

Another thought, you're using a six plate cell, so three 'pairs' of plates and putting 12v through it. This results in 4v per 'pair'. One factor that has come up more than once here is that 1.23v (approx) is all that is needed per plate pair to produce gas, any extra voltage will just result in heating issues.

You could either drop to a lower voltage line to get you nearer the 1.23v per pair or add extra plates to do the same job.

Uwee
08-07-2008, 10:20 PM
I dont think the plates are heating up. But I will find out, I think its just the wires.

It is wires in parallel and then when I switched it to series thinking that would help it was drawing really low voltages but still within range.
1/2:2.33
2/3:2.49
3/4:2.33
4/5:2.45
5/6:2.43

The amp draw on that was only .41 amps???

I am so lost by these results. I think something is really messed up and I just dont realize.