<h1>That part seems dubious</h1>
<p>Your part is labeled <a href="https://www.finglai.com/products/sensors/cylinder-proximity-sensors/M18-8mm/LJ18A3-8-Z_BX.html" rel="nofollow noreferrer"><code>LJ18A3-8-Z/BX</code></a>. That is a Z/BX type sensor of the LJ18A3-8 series - that first part dictates an M18 outer thread and thus dimensions and a triggering distance of 8mm. <a href="https://reprap.world/datasheets/LJ18A3-8-ZBY.pdf" rel="nofollow noreferrer">Z/BX indicates</a> NPN NO, so a normally open sensor of the <a href="https://www.arrow.com/en/research-and-events/articles/npn-vs-pnp-in-circuit-design-and-industrial-controls" rel="nofollow noreferrer">NPN type</a>. However, that labeling indicates an inductive sensor with a required <strong>supply voltage of 6 to 36 V</strong> and a power draw of 10 mA between the supply and ground line and a digital output signal of 300 mA.</p>
<p>There is a variant in existence, that has a 5 V supply voltage, but its part number is different by 3 characters: <a href="https://www.finglai.com/products/sensors/cylinder-proximity-sensors/M18-8mm/LJ18A3-8-Z_BX-5V.html" rel="nofollow noreferrer"><code>LJ18A3-8-Z/BX-5V</code></a> - the appended <code>-5V</code> is crucial to show it differs from the standard!</p>
<h1>The Ender-3 Board</h1>
<p>The Ender-3 board has a 24 V input from the power supply and runs its end-stops on 5 V logic. That would suffice to connect the output of a <code>LJ18A3-8-Z/BX-5V</code> sensor directly to a sensor pin.</p>

CC BY-SA 4.0
2021-05-10T15:12:43.737Z
Hi I did test it with 5 V source and see if the led comes on near a metal object, and it does and it seems bright, there’s 2 wires going to the end stop and I was wondering how to wire it up?
Imran Ali
CC BY-SA 4.0
2021-05-10T19:36:35.610Z
@ImranAli then the part is mis-nomed, for wiring it up, you should test the output voltage on the other wires on 5 V input
Trish
CC BY-SA 4.0
2021-05-15T14:02:07.150Z
There’s quite a lot of sellers selling them and they all say 5 V on the label on lots of websites , so I’m presuming it Is 5 V and most 6 V onwards won’t even work at 5 V but this does actually work at 5 V.
Imran Ali
CC BY-SA 4.0
2021-06-08T12:38:50.953Z
@ImranAli I would suspect this is the 6V-36V version and the sellers are stretching the truth a bit by claiming it (also) works at 5V. A sensor designed for 6V probably also works at 5V but may or may not be reliable.
Tom van der Zanden
CC BY-SA 4.0
2021-05-09T10:42:27.717Z
2021-05-09T11:20:28.263Z
2021-05-09T11:20:28.263Z
Trish
<p>The schematic attached to the cable shows the wiring for the sensor. There is BN+, BK, BU-; these are presumably the brown, black and blue wires respectively. The schematic BN+ is the positive supply wire (should be connected to 5V) and BU- the negative wire (should be connected to ground). BK is the output wire and should be connected to the endstop signal pin.</p>

CC BY-SA 4.0
2021-06-08T12:35:33.180Z
2021-06-08T12:35:33.180Z
Tom van der Zanden
<p>I’ve got this proximity sensor which is a 5 V, it doesn’t say it can be used over 5 V. Can I use a buck converter or is it possible to wire it up direct to a 5 V source on the Ender 3 V2?</p>
<p>What I don’t understand is where to wire it direct to 5 V on the printer or if I use a buck converter then where does the 3rd wire go to on the printer?
If it goes to the signal wire on the Z endstop then which one is the signal wire?</p>
<p><a href="https://i.sstatic.net/0yHTW.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/0yHTW.jpg" alt="enter image description here" /></a></p>

CC BY-SA 4.0
2021-05-09T03:53:31.540Z
Welcome to 3D Printing SE and thank you for your contribution. When you get a chance, please take the [tour] to understand how the site works and how it is different than others.
agarza
<creality-ender-3><creality>
How to wire 5 V proximity sensor Ender 3 V2?
Imran Ali
# How to wire 5 V proximity sensor Ender 3 V2?

(Asked by: username_0 on 2021-05-08)

I’ve got this proximity sensor which is a 5 V, it doesn’t say it can be used over 5 V. Can I use a buck converter or is it possible to wire it up direct to a 5 V source on the Ender 3 V2?

What I don’t understand is where to wire it direct to 5 V on the printer or if I use a buck converter then where does the 3rd wire go to on the printer?
If it goes to the signal wire on the Z endstop then which one is the signal wire?

[![enter image description here](https://i.sstatic.net/0yHTW.jpg)](https://i.sstatic.net/0yHTW.jpg)

**Tags:** creality-ender-3, creality

> **Comments:**
> **username_1**: Welcome to 3D Printing SE and thank you for your contribution. When you get a chance, please take the [tour] to understand how the site works and how it is different than others.  

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## 2 answers

### Answer by username_2 on 2021-05-09. Score: 1

# That part seems dubious

Your part is labeled [`LJ18A3-8-Z/BX`](https://www.finglai.com/products/sensors/cylinder-proximity-sensors/M18-8mm/LJ18A3-8-Z_BX.html). That is a Z/BX type sensor of the LJ18A3-8 series - that first part dictates an M18 outer thread and thus dimensions and a triggering distance of 8mm. [Z/BX indicates](https://reprap.world/datasheets/LJ18A3-8-ZBY.pdf) NPN NO, so a normally open sensor of the [NPN type](https://www.arrow.com/en/research-and-events/articles/npn-vs-pnp-in-circuit-design-and-industrial-controls). However, that labeling indicates an inductive sensor with a required **supply voltage of 6 to 36 V** and a power draw of 10 mA between the supply and ground line and a digital output signal of 300 mA.

There is a variant in existence, that has a 5 V supply voltage, but its part number is different by 3 characters: [`LJ18A3-8-Z/BX-5V`](https://www.finglai.com/products/sensors/cylinder-proximity-sensors/M18-8mm/LJ18A3-8-Z_BX-5V.html) - the appended `-5V` is crucial to show it differs from the standard!

# The Ender-3 Board

The Ender-3 board has a 24 V input from the power supply and runs its end-stops on 5 V logic. That would suffice to connect the output of a `LJ18A3-8-Z/BX-5V` sensor directly to a sensor pin.

> **Comments:**
> **username_0**: Hi I did test it with 5 V source and see if the led comes on near a metal object, and it does and it seems bright, there’s 2 wires going to the end stop and I was wondering how to wire it up?  
> **username_2**: @username_0 then the part is mis-nomed, for wiring it up, you should test the output voltage on the other wires on 5 V input  
> **username_0**: There’s quite a lot of sellers selling them and they all say 5 V on the label on lots of websites , so I’m presuming it Is 5 V and most 6 V onwards won’t even work at 5 V but this does actually work at 5 V.  
> **username_3**: @username_0 I would suspect this is the 6V-36V version and the sellers are stretching the truth a bit by claiming it (also) works at 5V. A sensor designed for 6V probably also works at 5V but may or may not be reliable.  

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### Answer by username_3 on 2021-06-08. Score: 1

The schematic attached to the cable shows the wiring for the sensor. There is BN+, BK, BU-; these are presumably the brown, black and blue wires respectively. The schematic BN+ is the positive supply wire (should be connected to 5V) and BU- the negative wire (should be connected to ground). BK is the output wire and should be connected to the endstop signal pin.


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