Electrolyte challenge copper wire size

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notquitesure
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Electrolyte challenge copper wire size

Post by notquitesure »

Hello! I bought the materials for the electrolyte challenge all separately (did not buy the kit), but have had a hard time finding 24 gauge bare copper wire (and only 5 ft of it). All I seem to find is much larger gauge at home improvement stores, "copper" wire for crafting, or multi-stranded wire that appears to be made of smaller than 26 gauge strands (I do not have an instrument to measure these strands). I thought I'd found some information stating that using 22 or 26 gauge wire is fine since they are also easily wound around the straw, and maybe that stranded could be ok (if not large gauge), but I cannot locate this information to double check. How small is too small a gauge for this experiment? What is the acceptable gauge range for it? Could 2 strands of smaller gauge be wound together and used? Are the crafting wires that are copper (and not just copper colored) ok to use?
williamcolocho
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Re: Electrolyte challenge copper wire size

Post by williamcolocho »

Hello,
Since you will be measuring at most in the milli-amp scale 22 or 26 gauge will be fine. The resistance of the wire will be slightly different but as long as you use the same setup it will be ok.

Multi-stranded wire should also work as long as you can make the mechanical connection to the straw. Multi-stranded wire typically has the gauge value printed on the wire insulation.

"Copper" crafting wire may be ok. If your multi-meter has a conductivity mode, you can use that mode to check that this crafting wire conducts as expected.

Side note based on your question:

Increasing gauge numbers denote decreasing wire diameters. Smaller diameter wires have less current-carrying capacity. This is not an issue at all for your experiment.

Let us know if you have more questions and good luck.
notquitesure
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Joined: Tue Dec 01, 2015 9:23 pm
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Re: Electrolyte challenge copper wire size

Post by notquitesure »

thank you. I apologize for mixing gauge with diameter. In my head, I meant larger diameter when saying larger gauge though I know that the larger number means a smaller diameter.

I looked at the receipt, and it says 18-1 bare copper stranded, so no insulation with printing on it. It's made of 7 strands, each of which is very small. I'm guessing like 28-32 gauge. So I take it that means it's 18 gauge (the whole wire). I can separate the wire into groupings to get an approximate 22 - 26 gauge, but I'm not sure how many strands to twist together to reach this size.
Would it matter if I use an 18-20 gauge wire instead of 22-26 for this experiment? E.g., would a "larger" wire not work? Is conductivity affected by a larger wire itself, or by virtue of the larger wire not being maleable enough to wrap around the straw?
Do I need an exact measurement of the resulting twisted strand groups if I separate the 18-1 stranded wire?
Should the individual wires be twisted tightly enough to look like a solid wire, or can they be looser?

Am I overthinking this?

And sigh. NEW QUESTION. My multimeter appears to only go down to 20mA, not 200uA, though the chart in the manual says the range is from 200uA to 10A. I see that the distilled water is to be measured using the uA setting. Do I need another multimeter? I'd buy a kit but I believe we don't have time to order and receive it.
HowardE
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Re: Electrolyte challenge copper wire size

Post by HowardE »

The distilled water is your control and you won't see very much current conducted by the water. You could simply measure it with your meter and note in your results that the current was essentially zero compared to the others. You can also acquire a meter that measures down to uA. Radio Shack (if you have one near you) has a couple in the $30 to $40 range that are quite decent and go down to uA.

Don't worry so much about the wire. As long as you set up something and keep it the same for the whole experiment you're fine. The wire gauge and type (solid) was chosen because it's easy to wrap around the straw and will stay in place. Any wire that you can keep in a coil around the straw will do just fine.

Howard
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