ok im trying to make a chlorine generator cell for a 18.000gal pool.
can i use.63 or 1/16 in titanium sheet grade 2 for the anode and cathode with out the mmo coating.
if not than can i use the sheet titanium for the cathode - and use TITANIUM MESH STRETCHED SCREEN WITH MMO COATING ON IT for the anode +
im looking at useing a dc transformer (elk-trg-1640 ) 16.5vac,45va is this tranformer going to work
with a dpdt switch so i can reverse the polarity every day.
and add a switch so i can ajust the power for less power or more.
Text
the cell 1 " wide 5" long 1/8" apart just dont now how many cells to make it or how far apart if i have it right. thank you all for any help
[Edited on 04/24/2011 by bmorrow]Xenoid - 24-4-2011 at 18:25
Good luck on making your own!
I would definitely buy a professionally made product in this case!
You'll need at least MMO coated Ti mesh for the anode and Ti mesh for the cathode. If you want a reversible cell, you'll need MMO for both electrodes
(of course)!
Modern cells are now mainly solid Ti sheet with MMO coating for both electrodes, as most are auto reversing to avoid build up on the plates.
Power requirements will depend on the electrode spacing, salinity, water temp. and flow rate, 45VA sounds a little wimpy. I gather commercial cells
run at several 10's Amps. 1800 gals is a pretty small pool, is it not, so you may not need much!
Edit: Corrosion is the biggest problem with these types of cell, and is virtually eliminated in the modern commercial designs. The electrodes are spot
welded to appropriately bent Ti straps, which are further spot welded to the heads of 6mm Ti bolts. The bolts pass through the cell lids with the use
of "O" rings and are held in place with Ti nuts. Don't be tempted to use stainless steel or any other "common" metals for this purpose!
[Edited on 25-4-2011 by Xenoid]bmorrow - 24-4-2011 at 19:53
ok if i try this should i have all cathode surfaces reacting with an equivalent matching anode surfaces. or start with cathode on the out side and
just work it out for ever how many plates i have untell i have cathode on the out side once more and if i do this can i still use a dpdt switch.
and if i put the wires in the tube can i just use silver solder on the wires to the plates. then put some 2 part apoxy around the wire and solder
joints
[Edited on 04/24/2011 by bmorrow]
[Edited on 04/24/2011 by bmorrow]Xenoid - 24-4-2011 at 20:30
Preferably use an equal number of cathodes and anodes, although it is not critical in this application. If you have more anode surfaces then the
current density will be lower for these and there will therefor be less wear, but when you reverse the current the opposite will be true.
Is it even possible to solder/silver solder to MMO/Titanium! I doubt it, although I have never tried. Epoxy deteriorates fairly quickly in these sort
of environments. Don't underestimate the ability of saline/chlorine solutions to wick past what appear to be good seals, and corrode metals,
especially copper wire!bmorrow - 25-4-2011 at 03:12
Ok i dont have titanium sheet with mmo on it so im thanking of spot welding a pice of sheet titanium sheet to the mesh coated titanium with mmo
coating on it.
Then bend the sheet to fit next to the lid and use titanium bolts and nuts with viton gaskits .
And try and find a dc transformer that is around 15 to 20 volts if i use more than 20 volts will it be safe or is there a chance of getting
electrocuted with higher volts
.
THANK YOU FOR OF YOUR HELP
[Edited on 04/24/2011 by bmorrow]
[Edited on 04/24/2011 by bmorrow]Xenoid - 25-4-2011 at 14:00
Yeah, that sounds about right. Here's how they do it on the commercial units:
I've used this same procedure for chlorate cells (a far more hostile environment) and never had any problems. Note the "O" ring is fitted around a
small piece of PVC (grey colour) which is screwed and "lok-tited" onto the bolt. The PVC - "O"-ring assembly fits into the counter-bore on the inside
of the lid. This may be more sophisticated than you may need (at least initially).
Your power requirements are more problematical, and you may have to determine them by trial and error.
The amount of chlorine you generate will be determined by the current flowing through the cell.
This in turn is determined by the overall resistance of the cell.
The resistance is a function of very many variables:
Electrode spacing, salinity, pH, temperature etc.
Ohm's Law is your friend in this situation! Current(Amps) = Voltage / Resistance
So the higher the voltage you apply to the cell, the more current will flow (within the limitations of the power supply). And the higher the
resistance (increasing electrode distance, lowering salinity, etc.) the less current will flow.
Really, you will need some sort of variable DC power supply (or at least a VARIAC) to determine initially what the voltage and current requirements
for you cell will be. Once you have determined what produces a satisfactory chlorine output, you can replace it with some sort of simple fixed supply.
Something like a relatively cheap 0-30 Volt - 0-5 Amp DC supply from an electronics supplier would be ideal for the initial experimentation.
I don't really see any other way around it, it is almost impossible to guess what your DC supply requirements will be, it will require a lot of fiddly
experimentation!
bmorrow - 25-4-2011 at 18:13
thank you for the photo can i please get a photo of the side view and front view thanks once more for all the help every one bmorrow - 25-4-2011 at 18:25
[Edited on 04/24/2011 by bmorrow]Xenoid - 25-4-2011 at 19:32
thank you for the photo can i please get a photo of the side view and front view thanks once more for all the help every one
No! I can't be bothered taking any more pictures! If you search this forum you will find some assorted chlorinator images, here are some, you may need
to scroll up/down;
do you thank if i use a HIGH - VOLTAGE DC GENERATOR supply : 9-15 Vdc./ max. 350 mA.
Output-voltage at HV point : approx. 7,000-8,000 volts(no load)
along with Using PWM (Pulse With Modulation) for controlling power to the cell
or just use a trim pot.
to ajust the power for the out put of the cell
[Edited on 04/24/2011 by bmorrow]
Not sure I understand what you are on about - stay away from high voltages!
What the hell has 7-8KV got to do with running a pool chlorinator! At a very rough guess you might need 5 - 10 Volts and around 10 - 20 Amps
especially now that I see your pool is 18,000 gallons and not 1800 gallons (I thought it was maybe a kids play pool).
I REALLY THINK YOU SHOULD BUY A PROFESSIONALLY MADE UNIT!
Re: welding a connector to Ti mmo-coated mesh
mrblister - 19-5-2011 at 11:38
I'm currently in the process of doing something very similar. I have a titanium mesh section coated with MMO/DSA and am trying to figure out the best
way to attach my anode terminal to it.
Unfortunately I lack easy access to a spot-welder, so I'm actually considering using thermite welding by way of titanium (IV) oxide and aluminum,
which should yield pure titanium metal. Does this sound like a good idea or could it destroy the mesh entirely? Would it help at all if I
also avoided submerging the welded area?
[Edited on 19-5-2011 by mrblister]Xenoid - 19-5-2011 at 19:29
....so I'm actually considering using thermite welding by way of titanium (IV) oxide and aluminum...
Good grief!... Just spot weld it, what could be simpler. There are plenty of simple, cheap, homemade designs around which use old microwave oven
transformers. Just Google it.
Alternatively, take it to an engineering shop, it will only take a few seconds, they'll probably do it for free!
Best thing is to spot weld on some Ti strap, bend over the ends, drill a 5-6mm hole in the bent over bit and put a Ti bolt through it and through the
lid. Don't use stainless steel or brass.
Best to avoid air space in the chlorinator cell as this is where most corrosion will likely occur. mrblister - 20-5-2011 at 11:29
Good grief!... Just spot weld it, what could be simpler. There are plenty of simple, cheap, homemade designs around which use old microwave oven
transformers. Just Google it.
Alternatively, take it to an engineering shop, it will only take a few seconds, they'll probably do it for free!
Haha, yes, I know — I just figured it would be another fun project considering I had the materials already. And thank you for the tip about the
volume of air — I certainly hadn't considered that and will definitely keep it in mind when I construct the cell.
