Wiring a chinese tool presetter.

Makes sense.
I later read that there is an LED, so presumably that is why it needs power and gnd. I would hook it up and see what you see with a multimeter.
It might be that you need to use the DMM in voltage mode, or in continuity mode, to figure out if it is a switch or a voltage source.

I finally had some time today to get back to this. Here's what I found so far:
Power it with the black/green makes sense. The specs say there's an LED but I certainly don't see one.

When powered, the red goes high when it exceeds the stroke. So that makes sense too.

Yellow is NC to green/ground and opens at the touch.

Does that make sense?

Did you ever get this working? I have been wanting to do this but never got around to it. If you have had success with this one I'd be pretty tempted to order one.
How hard is it to set up the machine to include using this in it's operation?

I'm pretty close but not there yet. When it comes to working with the 'angry pixies' I'm really terrible. Actual electronics frustrates and confuses me.

As noted above, if I wire: Green -> Ground, Black -> 24V, Red -> Input
I get a signal on the input when the switch is pushed all the way down in the travel. I assume this is the 'machine protection' to act like a limit switch.

I don't get a similar signal on yellow though. Instead, yellow seems to be normally closed with green and opens at the first touch.

I suppose I could wire green->24V Yellow->Input and ignore the other two but I don't understand how to make both circuits work at the same time.

For about $65 bucks, the quality looks pretty nice. It's solidly built. No detectable play in the switch mechanism but I don't see any LED as noted in the spec.

sliptonic wrote: I don't get a similar signal on yellow though. Instead, yellow seems to be normally closed with green and opens at the first touch.

Exactly as PCW predicted?

What is your input interface? If it is a parallel port then you can connect the yellow wire direct to a parport pin (as these are pulled up and can be switched by connecting to gnd).

I suppose I could wire green->24V Yellow->Input and ignore the other two but I don't understand how to make both circuits work at the same time.

If it's a proximity switch inside then that will kill it.

Does the red wire go to +24 when the switch is pressed all the way and is OC otherwise?

It's the inverse of what PCW said. Yellow grounded to green normlly but opens when tripped.

Wiring into a 7i77.

Yes. The red goes to +24 when fully pressed.