forum.cncdrive.com

Hi
Have just installed a fixed location probe/tool length sensor (Probe 1) and would like to utilize my old probe (probe 2, simple 2 wire switch, for material z height).

The goal is to eventually set up semi-auto tool changes with M6.

Looking for best options for which input to choose for my 2-wire probe.

All isolated inputs on Port 2 are occupied as I use 4 NPN inductive proximity switches, plus E-Stop, plus new probe 1.

If I used one of the analogue-in ports for probe 2, would that work or is it bad practice to mix the probe voltages?

Thanks Steve

You can't use the analog input, as it can't be assigned to anything.
Get a cheap breakout board and use Port 3.

qldsteve wrote:All isolated inputs on Port 2 are occupied as I use 4 NPN inductive proximity switches, plus E-Stop, plus new probe 1.

Are the four proximity switches NPN/NO or NPN/NC? I'm assuming these are for the limit/home? You can consolidate them onto fewer inputs. For example, if they are NPN/NO for limits/home, you can connect the outputs in parallel to a single input pin. If they are NPN/NC, you can connect them in series with the same result (fewer inputs).

See page 23 (section 9.3.1) and page 24 (section 9.3.3.1) of the AXBB manual. Section 9.3.3.1 shows mechanical NC switches, but the concept is the same for NC proximity switches.

I should add: Since you're not likely to be using both probes at the same time, you can probably consolidate those onto a single input pin as well. That's assuming they are the same type of switch (NC or NO).

Get a 5/6 axis parallel breakout board that's rated for the voltage you're probes are using.
Get an IDC26 to DB25 cable.
Plug them into port#3.
Presto, another 12 outputs and 5 inputs for them.

I appreciate all of your replies and recommendations given.

The two probes were different, NC & NO and I use the two of my y axis sensors for auto-squaring, so not too keen on putting any of these in series or changing things that are working well.

I have taken your advice and will order a breakout board and matching cable, which will also allow for any additional future expansion.

Thank you.

There are a-lot of breakout boards available, are they all compatible ? Can you give an example of a inexpensive board that would work ?
Thanks....

valhallaCNC wrote:There are a-lot of breakout boards available, are they all compatible ? Can you give an example of a inexpensive board that would work ?
Thanks....

I ended up taking the convenient route and buying the UCSB single port breakout board that shipped with the correct cable online here in Australia.

I did do some searching for something a little cheaper and I found that the extra shipping for two separate items plus the delivery delay from overseas was not worth the saving in my case.