2
Hey, you are supposed to be explaining galvanic corrosion today. It’s fascinating stuff, you know.

1
I know but I’m not ready. You know that is how a battery works, among other things, right?

2
Uh, sure I do. Batteries and me go way back, rechargables are the bomb!

1
Right, yeah, whatever. When you charge a battery you actually force electric current through it backwards. Did you know that?

Also, a dead AA (UM3) battery bounces if you drop it and a good one doesn’t.

And do you know about electrolytes too?

2
You bet, electrolytes are in sports drinks and serve as an anti-bounce mechanism in a battery. So weird.

Also, a 1.5V battery is actually like 1.6 volts because to get 1.5 volts you have to overcome resistance in what is being run, just like a car alternator puts out something like 13.5 volts.

1
Uh, right. Different electrolytes, really. Well, OK, OK, let me do a short take. Electrolytes promote electrical flow, like the acid in a car battery or lemon juice. Now, let me state unequivocally that electricity and especially electronics is a BLACK ART!!!!! I know, I studied electronics once upon a past life and it was good to me. But it is magic, or maybe almost voodoo but no chickens involved!

Now, onward.
All metals, compared to gold, are rated for and listed on something called the ‘anodic index’, which name I had to look up because I forgot. Remember from high school science that a cathode is a positive current device (normally) and an anode is a negative current device(again, normally)? If you put them both in an electrolyte solution, electrons will jump the ship from the anode and flow to the cathode and this ‘negative’ flow will produce a ‘positive’ current from the cathode. Presto-chango, we are inventing the battery.

Did you get that? Electrons flow the opposite direction of a positive, useable current, cause the flow of a usable, positive current.

2
That don’t make no sense a’tall! It’s like turning left to go right!

1
I told you it is a BLACK ART, remember? Think about a lightning pre-flash, and why you can smell ozone before it strikes. You know if you smell ozone when in a storm you are maybe 10 seconds away from a lightning strike and you better run like hell from that spot.

Anyway, if a person were to build something, lets say an outdoor light fixture, and put its mounting together with zinc plated nuts (the standard, cheap stuff) on a corrosion resistant steel conduit with electrical wires running through and install it in the desert, it would be fine for about a million years. If you installed it in, oh let’s say your beach house in Florida, it would fall apart in about 3 or 4 months, at the best. Why, you might ask.

2
Yes, I am asking. ย Why, WHY? And that lightning thing is be-weird, dude!

1
Why? Because the salt air and salty condensation, salty rain, salty fog, whatnot, acts as a solution that conducts electricity, just like that electrolyte we mentioned before and electrons flow from the cheesier metal to the higher indexed metal, causing corrosion and failure. Light fixtures are not air-tight, as you know. Yes, don’t mess with lightning, for sure.

2
So the whole shebang will be ruined? Kaput? Trash? So how come batteries don’t do this? And what’s wrong with taking a shower in a storm, anyway, huh?

1
Batteries do that, actually. What do you think a dead battery is? One whose electrolyte is no good any more, basically. Even unused flashlight batteries will corrode internally. Nothing wrong with taking a shower with electrically conductive pipes in the ground and water mixed with lightning, nothing at all, really. Oh no, nothing. (think heavy sarcasm)

There are a few ways to protect light fixtures and other stuff from corrosion. One, bolt on a ‘sacrificial metal’, like zinc and that will be eaten up first. That is what we put on salt-water boats, BTW. Just replace these sacrificial metals as they corrode away. Two, plate the heck out of the metals so they are protected (which is what we did after I proved this was the problem, not water damage, to not-so-smart-about-electrical current flow-engineers where I used to work). Three. Install an external DC source that neutralizes all this electrical flow (corrosion) in the metals. You see DC meters on poles and buildings with lots of aluminum conduit going to steel electrical panels filled with copper wiring. In New Orleans, for example.

2
Wow, so that is what those meters are for. I wondered and I just happen to have a picture.
๐Ÿ™‚

Note 1: there are a bunch of fancy laws and formulas but the only one we need to know is Murphy’s Law. If it can go wrong it will.

Note 2: next post will be about ‘Photographers’, hahahahaha. Just wait!

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