Sinking and Sourcing PLC Inputs with PNP NPN Sensors

We’re going to talk about sinking and sourcing PLC inputs, PNP and NPN outputs, how to determine which type of sensor you need depending on your PLC input, and how to wire your PLC input or PLC output.

Items used in this video:

[TimWilborne]

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[danstaifer]

How I remember- Count the Ns. PNP has one N so sourciNg. NPN has 2 Ns so siNkiNg.

[larslarsen]

Your videos are a great help. I’ve been building control systems for about 40 years, and I’m still learning. It would be a big help to some if you did a video on encoders / open collector inputs, etc. I do about 2 systems a year with encoders, and they can be pretty confusing to anyone just starting out. I really appreciate the work that you do on these videos.

[Dadjokes]

You sir, are awesome! My journeymen have explained this to me but I like how clear and to the point you are on all electrical topics. Thank you!

[pedalharder]

I’m sure someone has already answered your question to why NPNs are faster than PNP. It has to do with transistor make up. The mobility of electrons is faster than the mobility of holes. Cute video!

[justinpuzak]

you're such a good dude Tim. you refused to put the manufacturer on blast that had misleading sinking and sourcing information. You don't care to hear about credentials. You care about the next generation of automation professionals. I hope to reach your level of skill and professionalism one day, and i can't wait to take your class.

[yeeher]

Thank you for in-depth explanation and it confirms what I thought it was. I’m a new industrial electrician trainee.

[Iisidjenejiirjrkgawdcvyyyt]

You included the AB manual as a ref! Nice!! :) Ok, so to do PLC's.... well, I have to pay attention to PNP and NPN but the simple side of me says, "It's a switch, it does not care, it is going to complete the circuit!" Yet an Output has power going OUT from it to something like a relay! the Inputs have power going into it because it needs to see the 24vdc coming in as confirmation that the input is indeed there.

[davidpalmer]

Hey Tim, I got a Controls /Automation Test Eng. Job at a Nutracueticals (Vitamin) packaging
Corporation in Phoenix. Interviewed with the Controls Engineer 08/23/2021. Left with him hiring me. Thank You for all the Excellent Educational videos. Now I went to George Brown University for PLC II, but its been awhile. David P.

[marwanabou-samra]

Love it, i watched so many video about sinking and sourcing they are fantastic but within 1 week i forget everything lol. Now with your simple picture everything gone stay for lonnngggg time in my head. Regards

[jacksonsimon]

Thank you for the time that you take to explain PNP and NPN sensors and how they work. I've learned a lot by watching this video. Once again, thank you very much.

[Matt-ebbj]

Just had my 3rd interview/ walk through at a juice bottling plant for an electrician position. Hoping I made a good impression with the controls engineer and others and land the job. You can only learn so much in vocational training and on the job. I feel like I'm learning everyday in this field. Thank you for helping me review basic skills, that are imperative to plant maintenance work. Very helpful.

[michaelhopkins]

Thank you so much! Currently struggling through a PLC class for engineering school...your video helped me a lot with understanding the wiring, concepts, and terminology. Cant wait to check out you other content! thanks again!

[bettomotta]

I was not understanding the reason why the PowerFlex inverter's wiring diagram shows an inverted logic regarding the polarity of the sink or source Digital Input. But after watching this video I realized that in this case, the reference is the wiring and not the internal connections of the digital inputs. Thank you for the explanation.

[automationartisan]

For one of my application (egg counting system) previously I used PNP, and the result was that I was getting short on the counts by 10k. I then used NPN, with 24V going to the PLC com and receiving a negative input on the PLC card, and the cout was aproximately perfect.

[alancordeiro]

Watch till the end of the video, it's worth it! Thanks Tim

[elevatesafe]

I swore if i watch this enough it would CLICK thats not a PLC PUN, by George I think IVe GOT it !...finally got it THANKS TIM

[shivrankrishen]

I'm a Electrical Engineer and learnt a lot from this guy. Thank You Guy.

[nworaobinna]

Best video explaining sinking and sourcing inputs or outputs. Clear and precise

[thatdudeoverthere]

I have been and Automation tech for about 8 years now. And do you know how much "vibrant" debate this topic brings haha. Specially with the new techs haha. Great Video.