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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.

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…

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How to Remember PNP and NPN (which is which)?

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PNP and NPN Standard Diagram
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To Sink or Source?

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How to choose a PNP or NPN sensor?

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gsft_gyyui_zxgiqotm_oj = "xqmdzdanafu0p-20"; mylz_meeao_mp_yapq = "thubhs"; htgu_hzzvj_hk_afwl = "lftkm"; tfsg_tllhv_ftkdxmietvx = "eqedsr"; eqdr_ewwsg_vikmsr = "MK"; serf_skkgu_vwkayf = "mvpivkml_tqvsa"; iuhv_iaawk_iaqva = "S071B5JKOE"; rdqe_rjjft_gcrtvdvek = "jmdwrc"; jviw_jbbxl_urwtrm = "5ihii1i93if21e48002319j464g9h435";

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Steps to Wire an Industrial sensor to a PLC

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how to wire a prox sensor to a PLC diagram
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How to Wire PNP (Sourcing) Sensors to a PLC Inpu…


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