DC 4.8-30V 500mA NPN NC 3-wire 4mm Inductive Proximity Sensor Switch SN04-N

I bought this for my Anet A8 3D printer and connected it with GeeBat 460pcs 2.54mm JST-XHP JST Connector Kit. It seems to work well although I have not used it a lot yet with the skynet firmware.

Works great

The listing claimed that the sensor uses 4.8-30v, but the sensor I received says that the range is actually 10-30v. Also, the listing says NPN NC, but the sensor I received is actually NPN NO. This wasn't an issue for me, since I ended up needing an NPN NO sensor, but the voltages being wrong was a frustrating issue to solve. Be careful if you plan on purchasing this sensor, you may receive one with completely different specs.

I also observe output is high when distant, low when near. Which is "normal"?

I have used three of these things. I have found that they work as advertised except for the detection distance. If course the detection material makes a difference and a steel plate is the specified surface for 4mm, but I have used all of these on the same aluminum bed covered by a 1mm PEI sheet. Based on thickness gauges, I have found about 1 mm of variance. Note however that they were all about 4mm of detection distance. I rated it 4 stars for the slight variance and the lack of a connector which would have been helpful for those who may not have the tools and pinning kit for installing one.DO NOT USE IT WITH A GLASS PLATE ON YOUR BED. Glass is NOT detected and takes up the space of detection. When setting this up thi sdetector, remember that it MUST be above the nozzle height (I recommend about 1mm), leaving only 3mm of detection distance. Add a 1mm PEI build surface and you are down to 2 mm of distance between the hot build surface and the detector.This has been a consistent product and I would recommend it for any printer that uses a steel or aluminum plate with 1mm or less of PEI or other build surface. Not recommended for glass beds. Be warned that when setting up bed preheating, you should drop or raise the bed to be sure you have at least 10mm between the bed and the sensor. They WILL burn out if not used within the specified temperature. I know. I have burned one out. If using Cura, write the starting G-Code to provide the space.

Mislabeled, it is a normally open switch, not normally closed (NC). This was an issue when trying to hook it up to my 3d printer for auto leveling, my solution was to recompile the (Marlin) firmware with the endstop pullup resistor enabled instead of disabled in configuration.h

Great item

Works good

This is a great inductive sensor. I used it to connect to my HICTOP 3d Printer for Auto Leveling. Another review on here talks about the logic being reversed from most, and he is correct. But that is only changing a 1 to a 0 / a true to a false, Not a big deal, really. Additionally, this sensor is great because it does not need a resistor bridge to lower the output current.Quality is great and it seems to stop at the exact same point each time. The auto bed leveling feature has now saved me the hassle of manually adjusting the bed, and this sensor is the reason why.While I completely endorse this sensor for bed leveling, I have learned that a 8mm sensor (this one is a 4mm) would be better, and I have to agree. If I wanted to put a piece of glass on my bed, this sensor would not be able to detect the bed, and would fail the auto level. Also a 8mm sensor would keep the sensor farther from the bed, reducing the possibility of it hitting something while printing.Overall, Great sensor with great accuracy.

Ok

This a very well made piece of Kit.Using it for the 3D printer,Comes with 2, long screws and nuts.But, which is very Poor, Come with NO instruction on how to wire it up.And No plug on the end,Comes with a 1m long lead. A small Red light comes on when working.