Alternator question

Your question does not seem to make much sense...??

I asked what are 1 wire alternators used for:

Powder coated ones are just ones that have been painted (power coated) i think.

Ones got a pretty "paint" type finish. Ones got a single BIG wire for the 13.8/14.4 output wire instead of the more sensible two (for flexibility reasons. They are both the same, connected together)

The question doesent make sense these are not "differences" because you can have a painted prettyfied single wire alternator!

The second one's easy - it's simply the external finish. Powder coating is a form of hard wearing 'paint'. They also seem to do chrome plated ones.

As regards the 'one wire' - I'd say it's US speak for an alternator that doesn't use a separate voltage sensing circuit. However, that particular one mentions 155 amps output, so I'd expect there to be two output wires - at least.