Auto bed leveling - voltage not going Low when triggered

I have been trying to get auto bed levelling working on my i3 but I just cant figure out this weird problem I have.

So with the normal end stop I have GND, + (4.95v) & S (4.95v). When the end stop is pressed, + stays the same and S drops to 0v. This is all working as expected

Now the inductive sensor. I have wired it up to the 12v/GND from the power supply and have made a voltage divider which gives me Brown/+ (12v), Blue/GND, Black/S (3.46v). With the Blue/S not connected to the board and a metal object is placed under the sensor, the voltage drops to 0v, then goes back up to 3.46v when it is removed. At this point the inductive sensor is behaving as I assume I want it too, it is doing the same as the end stop.

Here is the bit where I get stuck. When I connected the Black/S wire from the sensor to the S for the Z axis endstop on the board, the voltages go weird. The voltage changes from 3.46v to 4.35v and when the sensor is triggered the voltage still drops but only to 2.87v so does not trigger as LOW.

Anyone have any ideas how I fix this? I am using a MKS Gen-2 V1.1 controller which I am guessing is probably the problem.

Thanks,

The only way I could get mine sorted with that board was to lose the voltage divider; works fine for me.

Get rid of the resistors and power the sensor with the 5 volts from the board or use an LM7805 instead of the resistors (what I do).

Thanks for the advice. I will give your suggestions a try and see what happens.

Hi there,

I use a MKS Gen V1.3 , also having problems with sensor wired to it. It was working fine on my ramps 1.4, but since I moved to the GEN, it just does´t stops the Z axis anymore. Is it safe to plug the Brown cable direct to one 5V output on the GEN?

thanks,

Hi,

What kind of sensor do you use tgmelo ?

++JM

Thanks ggherbaz! Lost the resistors and plugged into the 5V out in the board. Working fine!