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wire termination for screw terminals

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electrolust:
https://reprap.org/wiki/Wire_termination_for_screw_terminals

Is that proper advice?

I'm wiring an LED driver. The terminals in question do have a flat pressure pad, and are tin plated. There is a mains voltage terminal and a control terminal. Both of these are meant to be used with solid wire.

It's clear from inspection that solid wire does not contact the terminal pads very well. Round vs flat, so you get limited contact. There's limited torque you can apply, so you aren't biting into the wire much either -- only enough to prevent pullout. This is a high quality product, so that must be within the design spec.

I'm wondering for the solid wires, should I squash them with pliers to get them flatter, for better contact?

For my stranded connection (to the LEDs), I can see if I just put the wire in, the strands flatten out and I get good contact. But given the way the solid wires connect, I wonder should I tin the stranded, or use ferrules. I would crimp on deutsch size 20 contacts as I have them and have the tooling already. It's equivalent to a small diameter ferrule. But it's clear that in the flat terminal, I would get better contact area with just the bare wire.

3.5A over 18AWG.

As I will be installing "many" of these in a difficult to access area, I want to ensure a stable connection.

electrolust:
Maybe it matters, this isn't literally a screw with a flat washer-like pad on it. it's a PCB mounted terminal strip. I suppose the mechanical aspect is the same either way.

themadhippy:
If it will fit fold the wire back on itself so its double the size in the terminal

Gregg:
From my personal experience:
For stranded wire a crimped ring or fork terminal gives the best possible connection; uninsulated crimps generally are easier to get a good crimp connection and don’t take up as much physical room. They are also much easier to stack more than one under a terminal screw.
If you insist on winding the stranded wire around a screw terminal, strip the end long but don’t remove the stripped part of the insulation; twist the strands tighter together and the stub of insulation will keep them together and provide a better end to help keep the strands under the screw head; after tightening, give it the tug test, wiggle it around and re-tighten; you’d be surprised at how much the copper strands compress together after manipulating them.
For solid wire: copper work hardens and flattening it seems like a good idea, but pliers seldom are smooth or parallel meaning you might not get as good of a connection as if you let the screw flatten the wire.  Lightly crimping and soldering crimp connectors with solid wire might be a good solution if planning on stacking several under a screw. 
On some old installations I have seen the stranded wire looped around a brass grommet and crimped to make a rudimentary ring terminal.

calzap:
I second Gregg's suggestion to use crimped ring or fork terminals on the wires.  Be sure to use a crimper that applies a set force (i.e. squeeze until it releases type).  Don't use the squeeze-until-it-feels-right, cheaper type of crimper.

Mike in California

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