my rust removal tank

[Screwdriver]

From that post I can see that you either misunderstand the terms 'regulated' and 'constant', or that you have difficulty with explaining it -- neither of which is an insult btw, but if you're trying to give advice it'd be nice if it were correct...

Well I must admit, I am struggling not to feel insulted but hey, if you don't really mean it, that's fine; it's you who are struggling to explain yourself.

If I was writing a thesis on the subject I would be more careful with my description and not use common vernacular which also has a related technical meaning. Like current dumping for example.

I'm not going to bang heads with you. The detailed technical explanation is irrelevant in this context though it is tempting to watch you try and explain the difference between "current limited" and "constant current" within the context of your disagreeing with my comments regarding typical battery chargers vs. PC power supply.

I introduce the conceptual difference between these two types of power sources merely to remind the casual viewer there is no such thing as a typical DC supply. Just because it says 12v on the box doesn't mean it's going to give you 12v to your tank. Nor can you just stick a bulb in series with <insert random device here> and everything will be fine.

Using a bulb is a waste of energy unless you want to see what you're doing. The best way to limit the current flow in an electrolysis tank without having to delve into the precise technology of your power supply is to vary the concentration of the electrolyte.

 

[J1nx]

Most lead acid chargers are because otherwise they would have to deliver the rated capacity of a battery if you connect it to a flat battery.

So if you have an 80 ah flat battery, an unregulated charger would try to dump 80 amps into it!

You seem to be a little confused. This is an incorrect statement.

Supply current will depend on the impedance, both input and output. A battery impedance isn't easy to measure but is generally very low, so with a capable power supply the current can be very high. It has almost no relevance at all the the capacity rating, bar the fact higher Ah cells generally have a lower internal impedance.

 

[Screwdriver]

You seem to be a little confused. This is an incorrect statement.

Supply current will depend on the impedance, both input and output. A battery impedance isn't easy to measure but is generally very low, so with a capable power supply the current can be very high. It has almost no relevance at all the the capacity rating, bar the fact higher Ah cells generally have a lower internal impedance.

That's all I am saying. Higher Ah rating batteries can draw more current when they are flat. The thrust of my argument being that battery chargers can be simple or complex and when used as a power supply for electrolysis, the easiest (guaranteed) method for regulating the current is by altering the concentration of the electrolyte.

But damn, I just went and used "regulating" again as if it was just a word. Go on then, bite my head off...

 

[123hotchef]

Do you currently have the ammeter in line to see what current is being drawn? If it's still within the <3A range, that would likely indicate your PSU is faulty. If far more current is being drawn, something is likely shorted.

no its all switched off 2 psu cant be faulty they work fine away from the tank on the bench

 

[J1nx]

That's all I am saying. Higher Ah rating batteries can draw more current when they are flat. The thrust of my argument being that battery chargers can be simple or complex and when used as a power supply for electrolysis, the easiest (guaranteed) method for regulating the current is by altering the concentration of the electrolyte.

But damn, I just went and used "regulating" again as if it was just a word. Go on then, bite my head off...

I won't bite for any use of words, that would be me throwing stones from my glass house!

Back on topic, why not try an adjustable power supply. If your not worried about products that get here on the slow boat then google 'DPS5015', pair that with a meanwell or similar 48v power supply and you can setup exactly what you need.

 

[123hotchef]

thing is i dont want to spend money on it all the bits have been recycled from other things in the home. I am sure the solution is too concentrated I did use a bag of soda to the tank

 

[MattF]

no its all switched off 2 psu cant be faulty they work fine away from the tank on the bench

Do you mean they work fine wth a dummy or other load, or just if you run them with no load?

 

[123hotchef]

no load or if i connect them just to the lamp they are both fine

 

[MattF]

What wattage is the lamp?

 

[123hotchef]

21W 12V

 

[MattF]

Looking at your post in the other thread, is that the tank you're currently using? You say the PSU is pulsing? If so, disconnect four of those discs from the supply and try it then. They're overkill.

 

[123hotchef]

no it just drops the voltage right down now but it was working fine for weeks

 

[J1nx]

Either PSU is faulty or you have a short and the PSU is current limiting.

 

[123hotchef]

just checked the resistance of the solution in the tank and I got 6.53 on the 20k setting not sure what everone elses solutions are at

 

[MattF]

Forget the solution. You're sidetracking yourself there. Check through a process of elimination. Check for any shorts, remove all bar the two end discs, and give it a whirl. If something was working fine and then isn't, you don't need to consider anything which hasn't changed, but merely find out what has.

 

[123hotchef]

nothing has changed exept the items were free of rush and the discs had a build up of rust

 

[MattF]

Right, back to step one...

Brush the loose crap off the anodes with a wire brush, put an ammeter inline and insert a piece into the vat. What happens, and what volts & current are you reading?

 

[123hotchef]

Right, back to step one...

Brush the loose crap off the anodes with a wire brush, put an ammeter inline and insert a piece into the vat. What happens, and what volts & current are you reading?

I will have a check tomorrow I am sure i can find something to stick in the tank even if it is just a horse shoe

 

[123hotchef]

Right, back to step one...

Brush the loose crap off the anodes with a wire brush, put an ammeter inline and insert a piece into the vat. What happens, and what volts & current are you reading?

ok so I had a investigation today with the tank I diluted the solution by 30L then ran some tests I was drawing just over 3amps at 13V

I did test the solution I took out too in a smaller tank and the results were much better Just 1 anode and a small piece I wanted to clean it came up lovely. But that was only drawing 1.5amps at 13V


Could I join two PSU together and run the tank that way to take the strain off of just 1 PSU

 

[Screwdriver]

You only need 1 amp and it sounds like your PSU is struggling to deliver any more than that.

Dilute the big tank a LOT more until you get about 1A. You've got a really good anode set up which probably means you have a very efficient electrolysis tank!

<edit> something I forgot to mention: the connection between anode/cathode seems to improve over time as the process gets going. This means the amps will rise from the starting position...