forum.cncdrive.com

Hi all,

Sorry if this a rerun of a much talked about thing:

I am setting up my board for the first time, first time user of UCCNC, I have a set of 6 NPN NC 3 wire proximity switches.

I have:

1 home for the Z

2 home for the Y

1 home for the X

1 limit for the X

1 limit for Y

On my controller my thoughts are I want to use 3 inputs as follows:

limits for the X+Y to 1 input
Home for the X+Y+Z for 1 input
Home 2 for the Y for 1 input

As I understand it this means uccnc will utilise gantry squaring.

Going by the manual for the board I can wire the multiple switches to these inputs in parallel, problem with that - NC wont work in parallel, they don't activate the input unless all active. I can obviously us separate inputs but I will run out I think?

Having searched online for wiring schematics for these 3 wire switches being wired in series, it seems possible, but rather complicated, some much more than others and I think surely it shouldn't be this difficult.

My take and this is the question I am getting to; the switch has 3 wires, when active it sends the signal to the output, they also do a 2 wire version, when active that one just breaks the circuit, that would work easily for series wiring and NC multi switches to 1 input. I could do the same with my 3 wire switch by just not using the 3rd output wire, to me it obvious by just using the brown and blue circuit it will behave the way I want, I just need to make sure the output is not joined to anything and is a dead end, am I right or am I missing something?

ian8555 wrote:am I missing something?

You're missing something. Unless the manufacturer states otherwise, the three-wire sensor is not simply a two-wire sensor with an extra wire.

Wiring the three-wire sensors in series isn't complicated. Let's use your plan for the X+Y+Z home circuit (three sensors). On all three of them, the brown wire gets connected to +V. The blue wire of the first switch is connected to Ground. The black wire of the first switch is connected to the blue wire on the second switch. The black wire of the second switch is connected to the blue wire of the third switch. Lastly, the black wire of the third switch is the final signal output, wired appropriately to the AXBB.