Content on this site may not be resold or reproduced. Copying is strictly prohibited. This post may contain affiliate links. See the Affiliate Disclosure for more information. Use of information on this site is at your own risk. View the Terms of Service.
Here on the blog, we spend a lot of time working with 5 VDC sensors and controllers (Arduino, for example). And, a lot of that knowledge is a great primer for getting into Industrial Controllers like PLC’s (Programmable Logic Controllers). However, when you start working with PLC’s and 24 VDC sensors you have to follow a slightly different wiring technique. Two very common, yet confusing terms in this space are “PNP” and “NPN”. This article aims explain these terms and provide real examples of how to wire PNP and NPN sensors to a PLC.
Table of Contents
How to Remember PNP and NPN (which is which)?
Before we dive into the wiring, let’s talk about what PNP and NPN are and some methods for remembering the two. You can think of the “N” as “Negative” and “P” as “Positive.” The middle letter is the letter connected to the common terminal. For PNP sensors…
About Liz Miller
Creator of LearnRobotics.org. Liz is a Robotics Engineer with experience ranging from Robotics Research at UPenn, Teaching at MIT, and Automated Manufacturing Engineering at United Technologies. Liz writes technical tutorials that anyone can follow and provides tips and tricks to help engineers grow their careers. Liz has authored over 100 pieces of unique content on this site. You can support her work here. Learn more about Learn Robotics on our About Us page.
You may also like
Welcome to Learn Robotics!
I’m Liz, a Robotics Engineer, and the creator of Learn Robotics.