Need Help with auto switching Reverse Polarity Circuit

[gunlocators]

Here is what I am wanting to do and cannot figure out how to accomplish it. I want to use 3 9v Batteries in Series and run +/- 27v in to a circuit and I want +/- 27 also out of the circuit. Heres where I am unsure. Although I know I could use a switch to manually change polarity. I am wanting a timed circuit to swap polarity. The timing is not too critical but needs to be between every 2-3 minutes to swap the polarity. Also would be nice to have a way to protect the out going 27v leads as they are going to be electrodes to have some sort of protection in case they were to touch and short out. Thats not absolutely critical but would be a nice feature. I have been stuck for 2 weeks trying to figure out how to get a circuit built that will allow for auto switching of polarity. Any help and assistance or ideas would be GREATLY appreciated.

A little more info I am building a Colloidal Silver Generator the Silver Electrodes go in distilled water. The reason for reversing polarity a time intervals and back and forth is to ensure one electrode is not eroded over time faster than the other. The process takes 2-3 hours so a manual switch would be a daunting task to baby sit the generator. If some one is willing to help me complete a circuit that will work, I would be very appreciative.

Thank you
Rodney W3LDR
Amateur Radio Operator

 

[Gryd3]

Here is what I am wanting to do and cannot figure out how to accomplish it. I want to use 3 9v Batteries in Series and run +/- 27v in to a circuit and I want +/- 27 also out of the circuit. Heres where I am unsure. Although I know I could use a switch to manually change polarity. I am wanting a timed circuit to swap polarity. The timing is not too critical but needs to be between every 2-3 minutes to swap the polarity. Also would be nice to have a way to protect the out going 27v leads as they are going to be electrodes to have some sort of protection in case they were to touch and short out. Thats not absolutely critical but would be a nice feature. I have been stuck for 2 weeks trying to figure out how to get a circuit built that will allow for auto switching of polarity. Any help and assistance or ideas would be GREATLY appreciated.

A little more info I am building a Colloidal Silver Generator the Silver Electrodes go in distilled water. The reason for reversing polarity a time intervals and back and forth is to ensure one electrode is not eroded over time faster than the other. The process takes 2-3 hours so a manual switch would be a daunting task to baby sit the generator. If some one is willing to help me complete a circuit that will work, I would be very appreciative.

Thank you
Rodney W3LDR
Amateur Radio Operator

Well... the first thing I noticed is that you want to use 9V batteries... they won't last very long...
Regardless of the powersource used however, you have two choices that I can think of.
A) Using 2 relays, or a single double pole relay. The circuit construction is exactly the same as an automotive window controller, or door lock controller.
B) Using a single relay, and a split rail power supply... You leave the neutral connected, and simply toggle the output between the positive and negative rails.

In either case, you will need a controller or timer... How often do you need to alternate the current flow? Does this process require DC, or can you use AC?
What is the expected current draw of the system?

 

[Bluejets]

555 timer should handle 2 to 3 minutes without too much accuracy and as above a double pole double throw relay to change over the 27v polarity.

 

[Arouse1973]

Well... the first thing I noticed is that you want to use 9V batteries... they won't last very long...
Regardless of the powersource used however, you have two choices that I can think of.
A) Using 2 relays, or a single double pole relay. The circuit construction is exactly the same as an automotive window controller, or door lock controller.
B) Using a single relay, and a split rail power supply... You leave the neutral connected, and simply toggle the output between the positive and negative rails.

In either case, you will need a controller or timer... How often do you need to alternate the current flow? Does this process require DC, or can you use AC?
What is the expected current draw of the system?

How do you get a +/- 27 Volt split supply from 3 x 9 Volt batteries? Does the OP mean he just wants to reverse the polarity and hence direction of current?
Thanks
Adam

 

[Gryd3]

How do you get a +/- 27 Volt split supply from 3 x 9 Volt batteries? Does the OP mean he just wants to reverse the polarity and hence direction of current?
Thanks
Adam

You don't from 3 9-V... I was thinking of an alternative power source.
The op is wanting to alternate the polarity on two probes, which will reverse the current flow, and help reduce the probes from degrading.

 

[Arouse1973]

This might work ok, as mentioned above the use of a relay. The timer circuit could be a 555 but I am not familiar with that device.
Adam

 

[Arouse1973]

You don't from 3 9-V... I was thinking of an alternative power source.
The op is wanting to alternate the polarity on two probes, which will reverse the current flow, and help reduce the probes from degrading.

Ok sorry misunderstood what you meant. Thought you had invented something there
Adam

 

[hevans1944]

@gunlocators might want to more thoroughly investigate "colloidal silver" by electrolysis. This process mainly makes ionic silver, NOT colloidal silver. Ionic silver is reduced virtually instantaneoulsy to silver chloride by chloride ions, particularly from stomach digestive acid or HCl molecules in the human body. To be effective against micro-organisms, nanoparticles of pure metallic silver must make physical contact with the organisms. It is the purpose of colloidal silver to provide this mechanism, but it is not easy to manufacture this stuff. For more information see this link.

73 de ACNS
Hopa

 

[KrisBlueNZ]

See also the Wikipedia article at https://en.wikipedia.org/wiki/Medical_uses_of_silver which includes the following:

Since the 1990s, colloidal silver has again been marketed as an alternative medicine, often with extensive "cure-all" claims. Colloidal silver products remain available in many countries as dietary supplements and homeopathic remedies, although they are not effective in treating any known condition and carry the risk of both permanent cosmetic side effects such as argyria and more serious ones such as allergic reactions, and interactions with prescription medications.

Although that article is probably written by shills for the pharmaceutical industry who want to prevent honest alternative medicine practitioners from making a fair living, right? LOL!

 

[hevans1944]

See also the Wikipedia article at https://en.wikipedia.org/wiki/Medical_uses_of_silver which includes the following:



Although that article is probably written by shills for the pharmaceutical industry who want to prevent honest alternative medicine practitioners from making a fair living, right? LOL!

I don't subscribe to homeopathic remedies, but there is some so-called alternative medicine that does appear to have some merit... at least to me. Colloidal silver, whether homemade or not, is probably harmless to the body, but there is no scientific "proof" it is effective at promoting health or well-being. What is fact is elemental silver kills micro-organisms on contact. We use silver-plated spoons and forks, but stainless steel knives, for our eating utensils, purchasing the silver-plate from estate sales. The plating is easily scratched and worn away with combo sponge and scouring pad. It is stiIl cheaper to replace worn items with "new" silverware from estate sales than to purchase solid sterling. I am not sure how effective our practice is, but I rarely get sick (except for a couple of heart attacks) since starting this practice about fifteen years ago. Never saw a need to attack the microbes in my body with silver either: we have a working symbiotic arrangement.

 

[Arouse1973]

I don't subscribe to homeopathic remedies, but there is some so-called alternative medicine that does appear to have some merit... at least to me. Colloidal silver, whether homemade or not, is probably harmless to the body, but there is no scientific "proof" it is effective at promoting health or well-being. What is fact is elemental silver kills micro-organisms on contact. We use silver-plated spoons and forks, but stainless steel knives, for our eating utensils, purchasing the silver-plate from estate sales. The plating is easily scratched and worn away with combo sponge and scouring pad. It is stiIl cheaper to replace worn items with "new" silverware from estate sales than to purchase solid sterling. I am not sure how effective our practice is, but I rarely get sick (except for a couple of heart attacks) since starting this practice about fifteen years ago. Never saw a need to attack the microbes in my body with silver either: we have a working symbiotic arrangement.

Yes your right Hop. I met a rep from a company who was selling silver thread cloth. We bourght some and has a local seamstess make us a small EMC chamber, it fitted on my desk, it was rather cute.It worked well. We were told hospitals use them as hand wipes because they kill bateria. Also the local police used small wallets of them to put the crims mobile phones in so they could not delete anything on their phones.
Adam