Rectifier for a silver cell.

[Yggdrasil]

I am not sure you need it, I work quite extensively with high amperage low voltage rectifiers (wireless towers and large redundant electronics that require 3.8-5vdc) but do you really think you will be throwing hundreds of amps through your electrolyte? Does your solution support it, will it remain cool?

Likely without you making your solution support it, it would only draw a few amps at best.

Even when I worked in a plating facility the amps were large due to the surface area of material and bath size, maybe I am wrong but it should only draw the power it needs you can't force it into solution.

more than open to being wrong, but this was my take while working with this type of process.

It all depends on the Electrode area.
If you run larger systems it may need hundreds of Amps even KiloAmps.

 

[adam mizer]

The power supply I have shown above is capable of 70amps on 12vdc wires and 22 amps on 5vdc wires, capable of huge amount of current.
You could get 1000w or 2000w power supply.
All the dcdc converters can connect to same circuit (cell) provided they are set to the needed voltage estimate of 3.5vdc and needed converters for current.
This can provide a huge current.
But I'm thinking just make a a bunch of silver cells depending on the volume of silver needed.

 

[kaisernine]

It all depends on the Electrode area.
If you run larger systems it may need hundreds of Amps even KiloAmps.

That's what I was thinking, the solution still has to be tailored to promote the reaction though.

Depending on the intentions of original poster it may be overkill to have a power supply with 100amps but multiple baths makes sense.

If you have some electronics experience OmniOn Power makes Dlynx III modules that can go up to 160amps and you can link them I believe up to 4 providing you with a large amount of amperage.
You need a input power source however the 12v on the psu would power them shown above.

 

[adam mizer]

OmniOn Power makes Dlynx III

Yes those Dlynx III appear very nice and have reasonable pricing.
I checked Arrow Electronics.
EDIT ADD: However I only see output of 2vdc, maybe I'm missing something?

 

[kaisernine]

My mistake you are correct read the input voltage, they would make a great deplating power option if trying to be selective with very low voltage.

For 12v power supplies I have used Bitmain you can buy them off ebay really cheap most go up to 133amps at 240v input.

buck converters to lower voltage will be hard to find handling 100amps but if you are doing multiple baths with each bath having it's own converter I think you are on the right path.

 

[adam mizer]

My mistake you are correct read the input voltage, they would make a great deplating power option if trying to be selective with very low voltage.

For 12v power supplies I have used Bitmain you can buy them off ebay really cheap most go up to 133amps at 240v input.

buck inverters to lower voltage will be hard to find handling 100amps but if you are doing multiple baths with each bath having it's own converter I think you are on the right path.

A person can connect the output of multiple converters at same voltage to make much more current.
So I'm estimating if I needed 40 amp current 3.5 vdc I could easily connect the output of 10 of those Amazon converters @5amps each thats 50amps and run a 40amp load at low voltage thats 80% load of the 10 cards.
Maybe mount the converters in a box as they are small. Maybe 10-20 of them as they are super cheap.
You could even put separate mini toggle switches one per converter (to turn off a circuit), you can mount banana jacks per how many you need.
You can even put a beefy copper rail in the box.
Can do more if you want, attach a digital amp meter read out attach a volt readout.
You have the ability to make what you want and control many possible loads and circuits or cells or 1 huge cell of multiple electrodes, what ever is needed.
I didn't do much searching on Amazon for low voltage controllable output and higher current capable converters.
But found those mentioned in link above posted.
Maybe more searching a DCDC converter with higher current and low voltage specifications can be found.

 

[kaisernine]

A person can connect the output of multiple converters at same voltage to make much more current.
So I'm estimating if I needed 40 amp current 3.5 vdc I could easily connect the output of 10 of those Amazon converters @5amps each thats 50amps and run a 40amp load at low voltage thats 80% load of the 10 cards.
Maybe mount the converters in a box as they are small. Maybe 10-20 of them as they are super cheap.
You could even put separate mini toggle switches one per converter (to turn off a circuit), you can mount banana jacks per how many you need.
You can even put a beefy copper rail in the box.
Can do more if you want, attach a digital amp meter read out attach a volt readout.
You have the ability to make what you want and control many possible loads and circuits or cells or 1 huge cell of multiple electrodes, what ever is needed.
I didn't do much searching on Amazon for low voltage controllable output and higher current capable converters.
But found those mentioned in link above posted.
Maybe more searching a DCDC converter with higher current and low voltage specifications can be found.

I am not sure you can parallel converters unless they are precisely the exact same voltage if one is out of spec I think one will carry the load and then the others will fail one by one. That is why they don't often do it in the field usually they have backups in case one fails but converts used in parallel are usually specified to do so specifically for that reason. You may be able to force them to work in parallel with a resistive load on the positive output but I don't know if the problem still exists.

Generally when you attach a power supply to a load the one that has less resistance will do the work and if the load exceeds that one power supplies rating it will fail and then the other supply will kick in and fail as well.

 

[adam mizer]

I think it can be done.
You possibly can also insert a rated diode on output of each.
There also are better converters with output current adjustments for limits.

 

[kaisernine]

If you get it to work let me know, I'd be interested, I have been messing around with low voltage supplies for a long time with work, finding a suitable one cheaply would be great multiple buck converters in parallel would be cheaper than any individual unit on the market.

I think it can be done.
You possibly can also insert a rated diode on output of each.
There also are better converters with output current adjustments for limits.

 

[Master Nater]

keep in mind when thinking about running those high amperages, you are going to need some descent sized conductors. if you do not, they will get overly-hot, and could potentially start a fire. especially if running this system at continuous duty (more than 3 hours straight).

running multiple smaller sources in parallel is no different than putting battery banks in parallel. ohms law says one source is just as good as another. as kaisernine pointed out, you just need to ensure they are all putting out the same voltage.

another thought - running multiple sources with their own feeds will allow you to feed your system with smaller, but multiple feeder conductors. and you can fuse each of them with a much more manageable fuse size.

good luck and happy refining.

 

[haveagojoe]

If you want low voltage and high current, it's best to lower the voltage at the transformer.

It's not too difficult to re-wrap a transformer to give a low voltage and then make a simple unregulated linear power supply using a full bridge rectifier, and a large capacitor to filter the voltage ripple to an acceptable factor (you will need to calculate the capacitor size, it will be large).

You can get a 200A diode bridge rectifier for about $20 or find one in a scrap plasma TV which will give about 70A. The rectifier will produce heat so you need one with a heatsink.

When wrapping the transformer bear in mind that the rectified DC output voltage will be 1.41x the unrectified AC voltage, minus the voltage drop across the diodes.

If you just need a high current voltage regulator you can do it with a bunch of mosfets. This would work fine with an ATX PSU or with a car battery charger for example.

Working with electricity is dangerous so it's important to calculate and verify your design carefully before building it. In the case of an electrolytic cell, the important and difficult calculation will be for the current draw, and you will need to design the power supply to be capable of supplying a significantly higher current than the cell actually draws. The question is, how big do you really want to go? Do you really need very high current?

I would suggest starting with a small cell, then build more small cells and run them seperately until you really need to build a larger one. Bigger setups usually suffer bigger problems. Also you don't want to run a cell which is too big for the amount of material you want to process, so using multiple small cells means you can be flexible. Don't forget that for a larger cell, you will have a larger amount of silver caught up in solution at any time, it's a bigger investment in the cell.

This video gives the calculations for solutions for a 4 litre cell.

 

[haveagojoe]

I'm looking for ways to step down the 12V output from the atx to 3V.

Check the label, it might be better to just use the 3.3V lines directly instead of 12V.
Also you may need a load resistor to ensure stability.

 

[Amol Gupta]

You could use fuse holder like this.
HERE
And fuse like this.
HERE
This would be used for a design that can run multiple silver bath setups.
Or possibly huge setup in one container.!!

Fuses will be used that's for sure, my fair guess is one can even use automotive fuses the are often rated for low voltage high current settings, better to loose a fuse than an entire PSU

 

[Amol Gupta]

That's what I was thinking, the solution still has to be tailored to promote the reaction though.

Depending on the intentions of original poster it may be overkill to have a power supply with 100amps but multiple baths makes sense.

If you have some electronics experience OmniOn Power makes Dlynx III modules that can go up to 160amps and you can link them I believe up to 4 providing you with a large amount of amperage.
You need a input power source however the 12v on the psu would power them shown above.

So the very first post I made has a link to the thread that I would like to extend, the mentioned thread talks about a fairly big 'self maintaining' silver cell

 

[Amol Gupta]

That's what I was thinking, the solution still has to be tailored to promote the reaction though.

Depending on the intentions of original poster it may be overkill to have a power supply with 100amps but multiple baths makes sense.

If you have some electronics experience OmniOn Power makes Dlynx III modules that can go up to 160amps and you can link them I believe up to 4 providing you with a large amount of amperage.
You need a input power source however the 12v on the psu would power them shown above.

The output voltage of the mentioned DC-DC convertor is 2V DC if I increase the voltage close to 3 or 3.5 I can increase the current output by more than 50% using the same tank.

 

[Yggdrasil]

The output voltage of the mentioned DC-DC convertor is 2V DC if I increase the voltage close to 3 or 3.5 I can increase the current output by more than 50% using the same tank.

No when you increase the Voltage the Current go down and opposite.
P=U x I where P is the Wattage and that is constant so when you increase the Voltage the current has to go down to maintain the Wattage and when the Voltage go down the Current go up.

 

[Amol Gupta]

If you want low voltage and high current, it's best to lower the voltage at the transformer.

It's not too difficult to re-wrap a transformer to give a low voltage and then make a simple unregulated linear power supply using a full bridge rectifier, and a large capacitor to filter the voltage ripple to an acceptable factor (you will need to calculate the capacitor size, it will be large).

You can get a 200A diode bridge rectifier for about $20 or find one in a scrap plasma TV which will give about 70A. The rectifier will produce heat so you need one with a heatsink.

When wrapping the transformer bear in mind that the rectified DC output voltage will be 1.41x the unrectified AC voltage, minus the voltage drop across the diodes.

If you just need a high current voltage regulator you can do it with a bunch of mosfets. This would work fine with an ATX PSU or with a car battery charger for example.

Working with electricity is dangerous so it's important to calculate and verify your design carefully before building it. In the case of an electrolytic cell, the important and difficult calculation will be for the current draw, and you will need to design the power supply to be capable of supplying a significantly higher current than the cell actually draws. The question is, how big do you really want to go? Do you really need very high current?

I would suggest starting with a small cell, then build more small cells and run them seperately until you really need to build a larger one. Bigger setups usually suffer bigger problems. Also you don't want to run a cell which is too big for the amount of material you want to process, so using multiple small cells means you can be flexible. Don't forget that for a larger cell, you will have a larger amount of silver caught up in solution at any time, it's a bigger investment in the cell.

This video gives the calculations for solutions for a 4 litre cell.

Thankyou for the links they are very helpful.

 

[Amol Gupta]

No when you increase the Voltage the Current go down and opposite.
P=U x I where P is the Wattage and that is constant so when you increase the Voltage the current has to go down to maintain the Wattage and when the Voltage go down the Current go up.

My observation was with respect to the silver cell provided my cell has a definite resistance R increasing the voltage will increase the current passing through the cell.

 

[Yggdrasil]

My observation was with respect to the silver cell provided my cell has a definite resistance R increasing the voltage will increase the current passing through the cell.

No it will not.
The resistance will impose an energy loss as a function of the current but that is independent of the voltage.

If you step down a voltage through an transformer the current will go up and vice versa.
Just an example.
If you have a transformer with an output of 100W and step down the voltage from 240V to say 3V you will get 100 = 240V x I which gives I = 100W/240V ==> 0.42A
After transforming it to 3V you get I = 100W/3V ==> 33.33A
Minus internal resistance and so on.
Very simplified.

 

[Amol Gupta]

No it will not.
The resistance will impose an energy loss as a function of the current but that is independent of the voltage.

If you step down a voltage through an transformer the current will go up and vice versa.
Just an example.
If you have a transformer with an output of 100W and step down the voltage from 240V to say 3V you will get 100 = 240V x I which gives I = 100W/240V ==> 0.42A
After transforming it to 3V you get I = 100W/3V ==> 33.33A
Minus internal resistance and so on.
Very simplified.

I get your point the bottleneck here is not the supply side of things.

Assuming there are not limitations on the input power, increasing the voltage applied to the cell will increase the current running through the cell.