Soory for english language (is not my natural language)!
I did a small test without then capacitor with a NPN NO model PL-05N sensor on a L7805CV voltage regulator.
After some research the lab works. I have 5v during the contact.
The next day, I disconnect all to redo the lab to the identical, and nothing else works.
I checked the cables, changed the test board, tested L7805cv by measuring the 12v input then 5v output. here are some info for those who will have a track
here is my video -->

 

Am I right in saying your using the 7805 to drop the output voltage to 5v? Because that's not really how you use a linear regulator......

 

the model is L7805CV. can you please guide me for the connection?

 

If your using it to drop the output to 5v and there is no other way (ie reducing sensor voltage), then what you need to do is have the 7805 permanently connected to supply voltage and switch the 5v from that (using a relay for example).
Remember the 7805 is 1A maximum or 1.5A for the CV (WITH heatsink), so be careful what you drive with that as well.

Looking at:

https://www.pcboard.ca/pl-05n-npn-proximity-sensor

150mA will drive a relay, but not suitable for directly driving a device of some kind, you may have blown your sensor

 

I use L7805Cv for printer bed leveling (it works very little time). My branching scheme is wrong?

 

The PL-05N is for test.
Normaly i will use the model LJC18A3-H-Z _BX

 

I can't do a schematic right now and i'm not very good at describing this in a way that the language barrier will allow your to understand.

 

Hello,

It looks like the intended sensor works on 6 to 36 Volts.
I only could find this chinese site:
https://detail.tmall.com/item.htm?s...=2&is_b=1&rn=a70fcf19b12944467fbdd9c0ba151021

Bertus

 

What is the 5V feeding?
Is it just the Prox out going into an input on a 3D printer?
And yes, your "branching scheme is wrong". You probably want to say your circuit diagram is wrong. But I am ignorant and can only speak one language myself. You are doing quite well!

Are you trying to switch a probe input on an Arduino 3D printer controller?
It does help if you put full details of your circuit here for us to read.
You can connect the PROX output to an optocoupler, like a PC817...
http://www.farnell.com/datasheets/73758.pdf

If the printer has pullups on the inputs, connect PC817 pin4 to the printer input and pin 3 to the printer com. This will pull the input down when the prox operates.
If the printer input has a pull down, connect PC817 pin 4 to +5V and pin 3 to the input. That will pull the input up to 5V when the prox operates.

 

I want to power the 12v proximity sensor by an ATX. Currently, my proximity sensor (LJC18A3-H-Z _BX) is on a voltage divider (5v output), all from ATX (it works very well). As I saw that there is the possibility to pass on L7805CV, I found interesting.

 

I can't do a schematic right now and i'm not very good at describing this in a way that the language barrier will allow your to understand.

tks no prob

 

I want to power the 12v proximity sensor by an ATX. Currently, my proximity sensor (LJC18A3-H-Z _BX) is on a voltage divider (5v output), all from ATX (it works very well). As I saw that there is the possibility to pass on L7805CV, I found interesting.

Yes, but what is the prox output feeding into? What is reading the prox? That is the question.
The way you are using the 7805 is not the way to go and if we know what you are trying to do we can help.

Here is another picture showing the prox connection.

Is this what you are trying to do?

 

what you mean "prox"?

 

what you mean "prox"?

Oh, sorry. It is short for Proximity Sensor. Prox is what they are commonly called in industry. At least it is in the factories I have worked in here in Australia.
So your PL-05N proximity sensor is a "prox"

 

the proximity sensor is used for the survey (topography) of the heated bed and Z-home (prob)

is my first texst Here it work with a voltage divider bridge

 

How were the original limit switches wired up? Was one side com or +5V? that is important.
What is your controller board?
And do not hook your Prox/7805 setup onto your printer as I think it may damage it.
I should be asleep now so will have to continue tomorrow.
Good night.

 

I use ramps1.4. the wriring on the prox is the blue cable sensor on pin Z_min - and the signal cable on pin Z_min S
Thank you for your help!

 

Hello,

I see that you have posted on several forums.
One other in english:
https://forum.repetier.com/discussion/1882/melzi-v2-with-repetier-firmware
and two in french:
https://www.lesimprimantes3d.fr/forum/topic/2940-branchement-du-capteur-de-proximité-ljc18a3-h-zbx/
https://www.lesimprimantes3d.fr/forum/topic/1272-problème-avec-laxe-y/

I have linked them here as they also contain some photos.

Bertus

 

I could not get to sleep.

You could try adding a 1N4148 diode between the Z_min S pin and the signal cable, with the stripe on the diode (cathode) towards the signal cable. That will stop the 12V from the sensor getting to the Ramps board and may still pull down enough to work the limit signal. The opto isolator is a better option as it fully protects the board from external voltages.

 

I could not get to sleep.

You could try adding a 1N4148 diode between the Z_min S pin and the signal cable, with the stripe on the diode (cathode) towards the signal cable. That will stop the 12V from the sensor getting to the Ramps board and may still pull down enough to work the limit signal. The opto isolator is a better option as it fully protects the board from external voltages.

can i follow your schema? with 1N418?