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  • LJC 12A3-4-Z/BX /NPN Capacitive Proximity Switch for printer A30
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LJC 12A3-4-Z/BX /NPN Capacitive Proximity Switch for printer A30


Shipping Weight:75g

Quantity in stock:9842


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This capacitive proximity switch is designed to improve the accuracy and efficiency of the auto leveling process for 3D printers. Able to detect both metal and non-metal building platform.

For those who 3D print a lot or 3D printing beginners, it makes leveling the build platform a no-brainer. This kind of proximity switch will enable your printer to take several bed leveling readings and calculate a level plane so your prints are always level. While printing each layer, you z-axis will be in constant motion to compensate for an un-level bed.


· Save time messing with springs and screws on your print bed. Run the Auto-level procedure before every print or just one time for each start-up of the printer.

· Less issues related to un-level print beds like parts coming up on one corner and nozzles jamming because the print starts too close.

Note: For Geeetech 3D printers, this capacitive proximity switch can only support A30 3D printer at present. Before your purchasing, make sure that the firmware of your printer is compatible with it.


Product Features:

Model: LJC 12A3-4-Z/BX

Output Type: NPN

Supply Voltage: DC 6-36V

Power: 500~600HZ

Detection Distance: 5-10mm (±5 adjustable)

Operating Temperature: -25~ +75

Wire Length: 15cm

Dimension: 12*60mm

Made from copper




Package include: 1pc x Capacitive Proximity Switch

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  • George Blomberg | 10/18/2020

    will this work with the A30 PRO

    • Jocelin Jia | 10/23/2020

      hello, yes ,it can work on A30 PRO

      • Marc PORTAZ | 11/24/2020

        Bonjour, est-il compatible avec la A30T?

        • Jocelin Jia | 11/25/2020

          hello, yes, it is compatible with A30T A30M A30 PRO A30

  • Stephan Thiel | 08/28/2019

    Thank you for the very fast delivery. The LJC 12A3-4-Z / BX / NPN Capacitive Proximity Switch has a great performance.

    • Jocelin Jia | 08/29/2019

      thanks for your comment, have a good day

  • Igor Rodriguez | 12/09/2018

    Hello my geeetech a10 heve the conection for this acessory, what i do do enable it in printer firmware?

    • Jocelin Jia | 12/10/2018

      Do you bought it or...? A10 can not support it, it can only supoort 3d touch, thanks

  • James McElhany | 07/14/2018

    Will the GTM32 Pro vb support the bed leveling sensor?

    • Jocelin Jia | 07/14/2018

      Hi James, can u tell me which printer you use? Currently,the printer A30 can use above sensor.


    Is it compatible with geeetech prusa pro b?thanks

    • Maria Olivier | 05/12/2018

      This switch use for geeetech A30,but we are testing on other printers,i will feedback when the test past,thanks

  • Jean Paul Carré | 04/22/2018

    hi i just ordered an A30. how to intall this sensor ? is the formware to be modified and how ? thanks

    • Maria Olivier | 05/05/2018

      Hi Jean, https://www.youtube.com/watch?v=_7XE--p6lSQ&feature=youtu.be you can refer to this video to install it.

      • Gary Graves | 06/18/2018

        Is there anything better than just that video? The document above doesn't give any form of instruction at all. ... As long as the sensor tip is 2.5mm above the heating bed, is that all we have to do? ... and then enable it in the firmware?

        • Jocelin Jia | 06/19/2018

          https://www.youtube.com/watch?v=toKVMLWjTn8 https://www.youtube.com/watch?v=toKVMLWjTn8,please refer this ,thanks

          • Gary Graves | 06/20/2018

            Thank You.

  • araken lotufo | 03/21/2018

    Is it compatiblw with prusa m201

    • Maria Olivier | 03/31/2018

      Hi Araken,sorry for late reply.Yes,but you neet to exchange the bracket of installing 3D touch module.

  • Arthur Gevaerd Neto | 01/10/2018

    Is it comnpatible with PRUSA I3 X? do u send us the code?

    • Zina Luo | 01/15/2018

      Hi Arthur ,yes ,but need resive the code by yourself .You can search some more on facebook or google for help.

  • Felix Manuel Manso Rojero | 11/24/2017

    Is it compatible with Prusa I3 Pro C dual extruder? Is it better than 3D Touch sensor?