You wrote: "I actually considered those-but my eyes glazed over as I tried to absorb all the stated specs...hoping to find out what the professionals use"
For wire terminals, there are two sizes to contend with, plus some variables.
First, the size of wire to be used. There are three sizes in general use, Yellow color-coded is for #10 thru #14 wire. Blue is #14 thru #18, and Red, which is for #18 thru #22. If you are using wire larger or smaller than this range, there is not any consistent color code, but terminals should be marked. For larger sizes, it is most common to use uninsulated terminals and put a heat-shrink sleeve over the body of the terminal.
Second, the size of bolt or screw they are intended to be secured to. Common sizes range from #6 (screw size) through 1/4" for the color-coded terminals discussed above. Larger sizes up to 1/2" are for heavy battery cables
and the like. For ring and fork terminals, these should match the size of the terminal strips, breakers, etc. that you are using - using washers to compensate for oversize terminals is a bad idea
Variables include heat-shrink coverings built into the terminal - these are very convenient, and an excellent idea for areas where your wiring
may get wet (like the bilge
area). You can, of course, use uninsulated terminals and supply your own heat shrink coverings. If you do so, I would recommend using "Dual wall" (sometimes "triple wall") heat shrink, which has a layer of heat-sensitive goo inside, which will melt when you shrink it and seal the connector inside.
I just bought this assortment of heat shrink on Amazon: https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1
- the "3:1 refers to the shrink ratio - 3:1 shrinks more (therefore tighter) than the more common 2:1.
If you are doing heat shrink, you really should have a heat gun - hair dryers and open flame are not good ideas. I got this one: https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1
And it works well for a "boat tool", though if I were doing boat electrical
stuff for a living I would have a heavier-duty model
Tinning/plating is another variable - generally, you want "tinned" terminals rather than plated (those Amazon terminals mentioned above are plated), but the difference is small - but you do NOT want bare copper! Also, the terminals should be made of copper, not brass or steel
You also want a good crimping tool for your terminals - DO NOT think you can get by with a pair of pliers! My favorite came from Rod Collins of Compass
Marine - unfortunately, his stroke has taken him out of the business for now (But he still has a great site for info on boat electrical
stuff - https://Marinehowto.com
) Do not cheap
out on your tools here - the Ancor and Klein tools are good (albeit pricey) - I'm sure others will chime in with their favorites.
For uninsulated terminals, I like this one: https://smile.amazon.com/Non-Insulated-Terminals-Klein-Tools-1006/dp/B00776SJJO/
Hope this helps!