Inductive Probe Issues

[Sandman50]

Issue: Z endstop will not trigger when a metal object is close.

I have an Omron TL-Q5MC2 2M inductive probe (stock part taken from my other Fysetc 2.4 build):

https://kb-3d.com/store/probes-swit...ve-switch-probe-npn-nc-5mm-4547648271585.html

A 2 piece Hartk stealthburner head:

Hartk Stealthburner 2 Piece Toolhead PCB - V4.0

This Toolhead PCB is designed and open sourced by Hartk for use with Voron Stealthburner. It features a streamlined 2 piece design for easy assembly and service with support for multiple configurations.

kb-3d.com

I've confirmed that the probe is getting 24V, ground is correct and the signal wire teases out to the mainboard via ohm meter.

Plugged into PA3 (Z endstop) on a Spider 2.3. (though I have not wired up a simple switch to see if that's working. The X and Y end stops work fine, so I don't think that's the problem).

The probe will turn the light off when a metal tool is close and the Signal >> Ground will flip states, but only by 0.6 volts.

The probe wiring is:

Brown >> 24V
Black >> Signal
Blue >> Ground

Printer is a Switchwire conversion.

relevant code section in printer.cfg

[probe]
pin: ^PA3
x_offset: 0
y_offset: 25.0
z_offset: 0
speed: 10.0
samples: 3
samples_result: average
sample_retract_dist: 3.0
samples_tolerance: 0.006
samples_tolerance_retries: 3

 

[shiftingtech]

Signal to gnd isn't a very useful measurement on that probe, since it pulls to gnd. Signal to v+ is more informative. However, it sounds like you probably have some other issue.

Misinstalling the v-/gnd wire is one common mistake with these toolhead boards: make sure that wire is going to the DC gnd (labelled v- on the meanwell psu) and make sure if you have a multi-psu system, that all v- are bridged together.

 

[Sandman50]

OK, thanks for the input. I'll check the ground wire tomorrow.

 

[Sandman50]

Traces the wires and my signal and ground where switched. Swapped the pins on the probe sensor and it’s all good.