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How do i work out the maximum current density for MMO


matchstick

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Im going to do a bulk buy on some high quality ruthenium iridium MMO mesh, but direct from the manufacturer the price is about the same as what laserred sells his for.

So i am stuck.
i have no idea if ill be just buying something somewhere else for more which does the same as lassereds MMO.

I need to test the proper stuff against the stuff we probably all use.

So, heres the issues, Laserred knows the current density of his mesh is 250ma/cm2, but the origin and composition is totally unknown, as is the designed purpose.
the one im considering buying costs the same as laserreds, which means its eithe better quality or laserred is selling scraps.
The manufacturer doesnt know the current density of their MMO, stating it depends on the use, though, they dont know how to work it out. they did however state in chlorate production the MMO has a lifetime of 2 years.


So, what i need to do is a stress test with some samples, see which one dies first/faster under the microscope under various conditions, the conditions however, i have no idea.

How do i go about doing this?

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Im going to do a bulk buy on some high quality ruthenium iridium MMO mesh, but direct from the manufacturer the price is about the same as what laserred sells his for.

So i am stuck.

i have no idea if ill be just buying something somewhere else for more which does the same as lassereds MMO.

 

I need to test the proper stuff against the stuff we probably all use.

 

So, heres the issues, Laserred knows the current density of his mesh is 250ma/cm2, but the origin and composition is totally unknown, as is the designed purpose.

the one im considering buying costs the same as laserreds, which means its eithe better quality or laserred is selling scraps.

The manufacturer doesnt know the current density of their MMO, stating it depends on the use, though, they dont know how to work it out. they did however state in chlorate production the MMO has a lifetime of 2 years.

 

 

So, what i need to do is a stress test with some samples, see which one dies first/faster under the microscope under various conditions, the conditions however, i have no idea.

 

How do i go about doing this?

 

I'd say get the new material. If the price is the same why buy used?

 

Most of us use the laserred MMO and calculate it for 300mA/cm2, and in practice the current reads prove this. The same for new commercial MMO. Another couple advantages to the new stock, 1) it's clean and ready to use (laserred's is often polluted with a brown smut that needs to be cleaned off with an acid etch), and 2) you can cut the new stock to whatever size you need for your power supply and cell setup (which cuts down on waste or scrap pieces sitting around).

 

They say the MMO lasts about two years? That's running heavy use for 24/7 or 730 days of 24 hour use (65,520 hours of running)! Sounds like several lifetimes worth of MMO for an amateur.

 

If you could buy a new car for about the same money as a tired, used car, which sounds like the best deal to you? Laserred's material works, but how long do you think it'll last? For an amateur, usually long enough.

 

To calculate the amount of MMO you need for a cell setup, read my blog, "Homegrown Oxidizers Part Two". There's a technique for calculating how many square inches of MMO for the power supply's peak current output. See if that helps.

 

WSM B)

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