Inductive sensors as endstop 24V
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Hi all,
i am planning to use Inductive sensors as endstop on all axis.
My System is running on 24V and i would like to run the sensors on 24 V.What do i have to do not to burn my board?
Thanks for help.
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For NPN NO (normally open) the easiest way is to add a diode in series (beware of the polarity).
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thanks alot....looks quite easy.
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What voltage are you inductive sensors rated for? I've found that 6-36 and 10-30v inductive sensors work fine running on 5v:
Proof that they work:
https://youtu.be/Bov87qlX0Gs
Proof that the readings are reliably repeatable:
https://youtu.be/_-fAMAnn3_sSo, if you are using this type of sensor, you don't need to worry about it, just plug them into the 5v sensor port, and job's a good'un.
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me again
i tried it with the diodes now.....
unfortunally non of the diodes worked properly.
non dropped the voltage below 0 always around 1.2 V which the duet doesnt measure as triggered.
by accident i used a diode which i measured in non triggered state 22.6 V by mistake i connected it to the board and it works.... nothing burned.
does that mean the duet has no problem with 22.6 v on that PIN?i am a bit confused
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You need a Schottky diode (for boards up to rev 1.3)
From the documentation:NPN output normally-open inductive or capacitive sensor
Duet 2 Maestro, or revision 1.04 or later of Duet WiFi or Duet Ethernet: you can connect the output of the sensor directly to the Z-probe IN pin.Other Duets: Connect the output wire of the sensor to the cathode of a diode, and the anode of the diode to the Z probe IN pin. The diode should preferably be a small-signal Schottky diode such as BAT43 or BAT85, but a small signal silicon diode such as 1N4148 works for some people.
All Duets: Connect the sensor ground wire to a ground pin on the Duet, and the sensor's + power wire to a suitable voltage (typically to VIN because these sensors usually need between 6 and 30V power).
Select mode 5 (P5) in the M558 command, also include parameter I1 in the M558 command.
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@whosrdaddy said in Inductive sensors as endstop 24V:
You need a Schottky diode (for boards up to rev 1.3)
From the documentation:NPN output normally-open inductive or capacitive sensor
Duet 2 Maestro, or revision 1.04 or later of Duet WiFi or Duet Ethernet: you can connect the output of the sensor directly to the Z-probe IN pin.Other Duets: Connect the output wire of the sensor to the cathode of a diode, and the anode of the diode to the Z probe IN pin. The diode should preferably be a small-signal Schottky diode such as BAT43 or BAT85, but a small signal silicon diode such as 1N4148 works for some people.
All Duets: Connect the sensor ground wire to a ground pin on the Duet, and the sensor's + power wire to a suitable voltage (typically to VIN because these sensors usually need between 6 and 30V power).
Select mode 5 (P5) in the M558 command, also include parameter I1 in the M558 command.
That only mentions the Z-Probe pin and not the endstop inputs, I would wait for clarification from Tony or David before hooking the sensor to an endstop input without the diode.
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Yeah missed that fact.
The endstop inputs are 3.3V and directly connected to the CPU, I believe the diode trick will still work but I don't know it will be safe... -
I do use 24v inductive sensors on my V1.04 board with diodes without issue.
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@tjb1 great which diode do u use ?
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@orthocube said in Inductive sensors as endstop 24V:
@tjb1 great which diode do u use ?
I bought both the BAT43 and BAT85 as described here but I don't recall which one I actually used on my setup, I think I used the BAT43 as I remember the blue color but either one should work.
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@whosrdaddy said in Inductive sensors as endstop 24V:
Yeah missed that fact.
The endstop inputs are 3.3V and directly connected to the CPU, I believe the diode trick will still work but I don't know it will be safe...Yes the same diode connection can be used with endstop inputs as with the Z probe.