Siemens S7-1200- Bit Logic Instructions NO, NC & OUT

you welcome to NFI online video tutorials this is the tutorials of siemens s7 1200 and in this lesson we are going to learn about bet logic operations and in meta logic operations we will understand I know NC and out commands of siemens s7 500 and then we'll have some exercise example so let's proceed with this lesson okay so first s bit logic instructions in letter n o and n o stands for normally open contact okay now if you if you know about industrial controls we also have an off switch okay so n s which is generally different from a no-contact if you if you know about n o switch we have a symbol which is like this it is like this so this is the physical switch which we connect to the PLC input okay so don't be mistaken this switch as a physical switch but this is the contact which is inside the later logic inside the programming so there's a difference between these two this is the switch physical switch which you press manually and this is the contact which is inside the PLC so it says the normally contact is closed it's on just like you press it this goes true so this goes on when the assign bit the value is 0 dot 0 now this is the address this address you will find here so this goes true by true means it it closes when this eyes ero dot 0 is true or equal to 1 okay so when this address is true or equal to 1 this bit will be true and it displayed as open or off when the address is 0 dot 0 is false or equal to 0 now this address is either true or false that thing depends upon the switch which is connected to this input or the signal which is connected to this input ok so let me show you one example like if you see if you see our camera now this is my first input ok i 0 dot 0 ok if this is true and this goes true by connecting a switch which is connected to its input okay so let me show you you might remember I have shown you this in the diagram but I'm just repeating this for your just so that you can have this thing in your mind so we have let me adjust my camera we have this simulator this is called PLC simulator okay a moment yeah now if you see this this is the first switch physical switch this is a toggle switch if I make it odd this will be true okay so if I turn it on this first input is true so inside the processor there's a contact we call it a no contact when this a no contact is tagged with the address of this input that contact goes true okay so this is my switch and inside it's a contact so don't get confused so this is just I want to clarify that we have switches and contacts separately and their functions are different okay so let me just put it back to focus my inputs and outputs yeah perfect so okay so let's move back to over presentation to see some examples okay now in Siemens dia in the Siemens software you will find this contact over here so if you open the software and if you want to enter contact it's available here this is the end of contact so when you click here and select this one this contact comes here this is the one way to get this contact the another way is you have this basic instruction pilot here and you go to bed logic operations and you take this a no contact from here a normally open contact and you can drag it like this okay this is the another way to have a contact so this was the a no contact in Siemens PLC now let's see some example we can connect a contact in series so you have two contacts tank one tattoo with the address is 0.0 and 0.1 you can getting that in series and if you connect that in series the output the output my output I mean if you if you connect anything here the output here this will be false if both the contacts are zero zero it means both contacts are false this will be false there will be no output here the output is Falls again if only one of the contact is true which is I 0.1 so if i if I make it true by pressing the switch on the output again this will know it to be on because the signal will not flow there is no signal here so if the first input is true if this is true when this is false again this will not be on because this is an and gate if you know a NAND gate in an gate if both the inputs are true if both the inputs are true then only you will have a signal from here which will pass from here and if you go to the output so this is what it means a series example in series this is made by a two and no contact in series so another example is parallel connections you know you can also connect that in parallel just we have seen in the last lesson of branches we have connected to and no contacts in parallel and if you see their logic if both are false there will be no output it will be no out but if both are false because there is no single coming from any of these contacts if one of the input is true so if either this is true then the signal will come from here and output will be on or if this is true again signal can come from here and go to here or if both are true then only out it will be on so this is a parallel logic you can make using two and no contact in parallel there's a very simple basic lessons from the Sun series and parallel contacts using normally open contact okay so I hope this makes sense and we will do an exercise to understand and work practically on the PLC so let's proceed with the next slide which is the same instruction but in FB d FB is a functional block diagram another programming language of PLC which is widely used in C means most of the time so this is the block symbol of an of a normally open contact in FB also you can find that in Siemens dia it's over here now you might be wondering how to move from letter to FPD so to move from letter to every it's very simple suppose I take this contact and I put a 0 not 0 so this is my contact I'm not using output so if I want to see this in FB d I don't have to design it again it is a function of the software you can right click on your main block and go to switch programming language and switch to FB d so you have this block here so I haven't connected anything on the output here so you have this input automatically linked to a block which is a new block and this is the input tag a start if I want to go back to later just right click here and go to later ok I hope this makes sense so we are understanding everybody so I move to everything so this is the FB d logic you can see like that's my right click on the main block and I move here so in the same example of series in parallel you have two contacts in series high 0.001 this is the series and if you notice this symbol and this is the symbol of series because if you know the iron gate is symbolized by the symbol and the drug table is same as what we have understand before so if you see the same thing in parallel you have the symbol like this greater than or equal into okay so this is these are the two inputs which are connected in parallel so if you see if you don't consider this symbol the block look almost similar but the symbol makes sense if there is a symbol like this this is an or logic if the symbol is like this this is the and logic and the truth table is same if any of the input is on and if this is on or if both inputs are on the output is true otherwise each faults in this case if both the inputs are true in this case in the last one the output is true so this is the and gate and logic or or logic I hope this this is this is clear ok so now we have normally closed contact ok now normally closed contact this is the opposite of normally open that's that's the shortcut to understand if you're learning PLC for the first time normally closed contact is the positive normally open contact okay so as I explained you in the last slide that if you have signal one to the input okay let me take the red color now if this is tagged as a 0.0 if you have on the force input the signal 0 then this will pass the signal ok this contact is closed when this is 0 this is what it says this contact is closed when the sign bit value is 0 dot 0 is false or a 0 dot 0 is 0 so this contact is closed or equal to 0 and it's open it's off so this contact will look like this this is open in the case if the signal coming to here is 1 okay so this is exactly opposite operation of your normally open contact that's why you have the symbol this is the invert logic so this is called normally closed okay let us we'll see that in the in the in the live demonstration ok so now the examples we have an our logic and we have a NAND logic so to NC contact in series makes an our logic to NC contact in parallel make the NAND logic now what is not at NAND nor is basically or plus not ok so if I take some something here now if you see here it says if both the inputs are 0 I told you if this is 0 this contact is closed if this is closed it will pass the value if this is 0 this is also 0 this is all the pass the value so the output will be true in this case now next cases it first is 0 second is 1 know if this is 1 this will be open okay this will be open so it will not pass the value so output will be false the value of first input will be just stuck here it will be way it will wait for this one that too close to pass the value so it will be off or it says if the first contact is true one second cannot go 0 so a first is 1 so this will be open so if this is open as I told you signal flow from left to right even this is closed hope it will be off because signal will not pass from here this is the third case last case says if both are open so if this is open and this is also open so in this in the last case it'll be like this if both are open output will not be on okay this this is very easy to understand so the output will only be on if both the inputs are closed okay the sistine nor logic used by two NC contact in series so what will happen if you can connects these two in parallel this will become a NAND logic nan is and plus not and plus not all plus not is nor and plus not is not now what is this nod means it says if both the inputs are true output is true of course it will be because if this is zero it means this will pass the signal if this passes signal r2 will be on also if this this is zero or we will will also be on so if both are zero pablor will be true if first is zero second is one so if this is zero of course this will pass the signal this is parallel this will make the output on if this is true this will be open but this will not affect the output because this is only passing the signal so if any of these two passes signal AB will be on that's why if any of the input is true and another is false or it will be true if both are false or a little bit true because this is NC but if both are open now if both are open this will be like this and this will be like this so if both are one nobody can pass the signal this will not pass a signal this will not pass the signal and output will be false this is a very simple representation for a NAND logic using two NC contact in parallel so you can practice that in your logic if you have a PLC simulator you can use any simulator because these are the basic fundamentals which you can practice on any PLC simulators okay so let's proceed to next slide the similar case we'll see in FPD now if you notice here in FPD this is the a block and I will just open all the elements and if you see here this is similar to an logic but you have this small circle here okay this circle represent not or you can say that it's inverse okay so this is a signal and this is the knot so if you just consider this tag combination with this symbol this means an NC okay if you don't find the signal then it means it's an N oh just we have seen in the last logic so if you find the signal this is a very small circle you have to notice that this means it's an NC contact okay that's an NC contact so this is the output now here this is not logic again - NC contact in series now why it's in series because it's an and logic we have and here so this uncie contact in series with this antigone that okay this is the same nor logic you will find in fe d similar in parallel you have this NC contact in parallel with this NC contact and you have this output I hope this makes sense you just have to focus on whether you have this bubble or small circle in your SPD or not if it is there it means it's an NC contact okay so let's proceed next and see some examples okay before coming to examples we have to understand an out coil because this will complete our later logic so we have this out coil in later logic symbolized by this symbol you have this two lines here which symbolizes an out contact and in FBD you have equivalent sign equivalent sign means whatever logic you have on the left will be given to the right okay so this is mentioned here in the software and to see an example we have this example of letter logic with series connections you understand the series in the before slide so this is the output coil so this output will be odd this is true if both the inputs are high both inputs are 1 so if you see the FPD we have connected the output block like this to my series input law there is no bubble here so this is a no-contact so this is this a no contact and this is this anokhin tag and this outburst is not good ok so this is the conversion of letter to everybody now it's up to you which language programming you find it easy you can practice that in your software otherwise you can learn both with this boot are very important if you're if you are considering yourself as a PC program if you're going forward for this profession you should learn these two basic languages ok so this was about out commands and everything and very logic ok you

Channel: Rajvir Singh

Views: 26,032

Keywords: PLC Tutorials, PLC Training, PLC Simulator, PLC Projects, PLC Lessons, PLC Lectures, Siemens S7 1200, Siemens PLC, Siemens PLC Commands, Siemens PLC training, Siemens Funamental commands

Id: s7pWhZgGVfg

Length: 16min 45sec (1005 seconds)

Published: Mon Jun 13 2016