high curent PCB connector

We've used a lot of those plugable connectors, never seemed like a problem to unmate them

doesn't have to be spring clamps,

We used a similar part, and it was very hard to un-mate. We use the version with the cam now, but only a few of their connectors have the un-mate cam.

And since the connectors are unmarked, we have to explain the pin numbering to our customers, with pictures in manuals.

if it had numbers you'd still need to explain what goes to what number, or just have the names/numbers on the box next to each pin

Imagine if D25 or USB connectors had random pin numbers on various products.

Used maybe 2-4,000/year of those at my last job. Our standard was to hold the cable so the wires were vertical and the screws that held the wires were towards you, like you were about to plug it in on a vertical pcb (as ours were). Leftmost pin is #1. Oh, you can put bare stranded wire in them but it's much more reliable to crimp a ferrule on each wire first. That way on high current wires (cabinet power was 10-13A on 12 ga stranded) you don't miss strands, and with tiny wires (some sensor leads were up to 22 ga) the wire doesn't slip to the side of the jaw on the end of the screw as you tighten it, ready to squeeze out a month after you ship it. Did a bit of shopping around and settled on ferrulesdirect.com, was always happy with their products.

Regards, Carl

If we have to crimp, we may as well use a Molex connector, which has pin numbers moulded in.

might as well have names instead of numbers, DB25 is used for all kinds of things, the numbers doesn't tell you anything