Virtual Relays and Holding Circuits for PLCs (Full Lecture)

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  • čas přidán 5. 08. 2024
  • In this lesson we'll examine virtual relays, software generated holding instructions, and the set and reset functions offered by most PLC programs. We'll learned that virtual relays mimic the behavior of traditional hardwired relays in that their associated instructions respond to the logical state of the virtual coil that can be energized or deenergized by the logic in a particular rung. We'll learn that virtual relays can extend the permissible number of contacts in a rung and be used to facilitate holding circuits, among other functions. We'll additionally examine software generated holding instructions that mimic the function of auxiliary contacts in that they respond to the logical state of a particular output that can be energized or deenergized by the logic in a particular rung. Finally, we'll examine the set and reset functions that selectively energize or deenergize an output and maintain this last asserted state until instructed otherwise. (Full Lecture)
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Komentáře • 21

  • @rudesback5013
    @rudesback5013 Před 2 měsíci +1

    This channel really made PLCs easier to understand and much more intuitive

  • @wowsuchhandle
    @wowsuchhandle Před 5 lety +26

    Amazing engineering videos without the indian accent, it's pretty rare to find on CZcams thank you.

  • @Logical_Controls
    @Logical_Controls Před 6 lety +12

    Ridiculously underrated channel. I haven't had any formal or professional training when it comes to PLCs, I just sort of picked it up from others at work and seem to have a knack for it. I wrote a program about a month ago and needed like 7 contacts all in series, funnily enough the first thing i tried was the backwards wiring haha made sense in my head at the time but it didn't work on a schneider smart relay so then opted for the virtual relay method. You've got a great PLC series going on. Thanks a lot from the UK.

  • @adisharr
    @adisharr Před 4 lety +2

    Excellent lectures by the way. These are some of the best I've seen.

  • @rayflint261
    @rayflint261 Před 4 lety +1

    You my friend are a true wordsmith. For this I’m extremely thankfull

  • @gyrgrls
    @gyrgrls Před 3 lety +1

    For decades, the thing that has thrown me off the most about PLA's and PLC's is the terminology. Even the schematics of old EM pinball machines were split into two formats: the actual schematic and the ladder diagram. This is how ladder logic was born. I always found it easier just to write a truth table to a PROM. Then in the 70's we had CPU's like the 6502 or 6800. Now we have Arduinos. Dedicated PLC's seem commercial and superfluous.

  • @brianvanheugten1796
    @brianvanheugten1796 Před 6 lety +4

    Amazing Lecture! You have amazing teaching skills. Keep up your hard work!

  • @beznerwow1948
    @beznerwow1948 Před 5 lety +1

    You did great - thanks 😀

  • @michaelcostello6991
    @michaelcostello6991 Před 6 lety +1

    Good lecture. Thanks you

  • @burakayan3360
    @burakayan3360 Před 2 lety +1

    awesome lecture.

  • @johnmilsom2179
    @johnmilsom2179 Před 2 lety +1

    Great lecture ty

  • @adisharr
    @adisharr Před 4 lety +1

    The contact limit you talk about must apply to programmable relays. I've never seen that in any other PLC unless it's very old.

  • @ledickin69
    @ledickin69 Před 2 lety +1

    Damn that was good! Txs

  • @ilsemiller6376
    @ilsemiller6376 Před 2 lety +1

    i love how you persist and maintain the terminologies used with different things....And not skip from one to another. it sort of embeds it into memory (atleast for me) when i think back on your videos. great channel.. question: the N/C on I1 presents as a N/O contact on the rung.. and the N/O on I2 also presents as an open contact but on input I2. is this correct? how do i diffuse the confusion with these? I'm fairly new to PLC's but have electrical experience and schematics, but this boggles me a bit

    • @bigbadtech
      @bigbadtech  Před 2 lety +2

      Check out the "Basic PLC Instructions" lecture at: czcams.com/video/ic9crSVVF9Q/video.html Long story short there is a difference between the electromechanical nature (ie: NO vs NC) and the programmed instruction (make vs break) and you are free to choose which combination you want.

  • @Time4yes
    @Time4yes Před 3 lety

    Everytime time when I think of latching, I would stress on how does I1 which is normally closed gets back to its original state after being pressed to stop the continuity. So thanks for explaining the spring and cylinder process.

  • @anismahmud3636
    @anismahmud3636 Před 5 lety +2

    nice

  • @styxhisdicksahammerdyxdyxd8467

    Your videos are amazing thank you! Are you an electrical engineer?

  • @adisharr
    @adisharr Před 4 lety

    I would avoid using 'safety' in any context unless referring to a safety rated system. I still see people trying to use standard PLC's for safety operations. At least explain that this is not a true safety rated system.