5v inductive sensor to Duet Wifi

So I have this LJ12A3-4-Z/BX-5V inductive M12 sensor I intended to use on the Duet Wifi for a Z/Bed sensor...
Thing is all the NPN inductive sensor setups I have found are for the 6v-30v version not the 5v

Is there anything I need to know

Edited 1 time(s). Last edit at 01/29/2018 07:31PM by JustSumGuy.

There are many vendors who claim their probes would work at 5V, I hope you have a real one...
With the 5V version you wouldn't need the low_drop shottky diode. And you have to put I1 ( capitol i1 ) in the config line of the z-probe, when it's a NPN NO type.

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o_lampe
There are many vendors who claim their probes would work at 5V, I hope you have a real one...
With the 5V version you wouldn't need the low_drop shottky diode. And you have to put I1 ( capitol i1 ) in the config line of the z-probe, when it's a NPN NO type.

Wouldn't the signal output be 5v and the logic of the Duet being 3.3v would I need a drop resistor across signal to gnd?
Can I pick up the supply 5v directly from maybe the paneldue 5v supply as its right next to the Zprobe pins and I wont be getting a paneldue?
I have not tested the sensor yet but it is labeled as a 5v sensor

AFAIK the input pins are 5V tolerant, maybe David can chime in here?
All the 5V pins are usable to feed the probe.

These NPN NO sensors normally have open-collector outputs, meaning they connect the output to ground when triggered and leave it in effect open circuit when not triggered. The complication is that if the ground wire to the sensor becomes disconnected, then the sensor supply voltage will get fed to the output pin via a diode and an unknown amount of resistance internal to the sensor. That's why we recommend using the Schottky diode. But if the supply voltage is only 5V then the risk of feeding excessive current into the endstop input or Z probe input is low anyway.

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dc42
These NPN NO sensors normally have open-collector outputs, meaning they connect the output to ground when triggered and leave it in effect open circuit when not triggered. The complication is that if the ground wire to the sensor becomes disconnected, then the sensor supply voltage will get fed to the output pin via a diode and an unknown amount of resistance internal to the sensor. That's why we recommend using the Schottky diode. But if the supply voltage is only 5V then the risk of feeding excessive current into the endstop input or Z probe input is low anyway.

ok, thanx for the input, taking a trip for a bit today so I will test all later, see if I can find some schottky diodes in my travels.... No harm putting it in just to keep things safe right

I will resume this issue come Sunday.

Thanx for the info guys, I was not able to track down a diode so I decided to plug it in and give it a go.

All worked fine!! used the +5v and gnd connectors from the paneldue connector and just ran the black signal wire to the Z Probe in pin...

Added M558 I1 to the start up and boom, everything just worked!!

Thanx again!