PLC Analog Inputs and Signals
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- เผยแพร่เมื่อ 7 ต.ค. 2018
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In this video, we are going to be talking about analog inputs to the PLC.
What do we mean by analog input? Analog values are continuous values, such as temperatures and pressures.
While we tend to think of them in digital terms, at some point we have to convert them from the continuous world into our digital world, and this is where analog inputs come in.
Voltage signals in the range of plus or minus 20 volts or so and current signals in milliamps are commonly used as both analog inputs to PLCs.
Every PLC manufacturer has I/O modules to deal with these kinds of signals, along with other, more specialized modules.
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#RealPars #PLC #PLCanaloginput
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please make a vedio about simens s7 300 plc to simens hmi tia v13 portal
special request
th-cam.com/video/umOqPiKcmQk/w-d-xo.html
I would add that some of the most important reasons why 4-20mA is used over 1-5V:
1. The voltage reading could be inaccurate due to cable resistance voltage drop.
2. The current read in the transmitter and the PLC are identical, for any value of cable resistance, thus the transmitter can sense if the current is not the correct value it intended to transmit so it can adjust its impedance in line to bring back the current to the correct value.
3. Two wire transmitter connects are possible with current but not with Voltage.
4. Under ange (lower the 4mA), over range (higher than 20mA), and wire break (under 3.2mA) can interpreted by the PLC.
5. Current circuit is a very low impedance (normally less than 750 Ohms) so less sensitive to electrical interference compared to Voltage signals.
6. Current circuits allow an easy connection of an indicator in the current loop as long as the total resistance in the loop does not exceed typically 750 Ohms.
Awesome! Thanks for sharing your knowledge with us, Santo.
Very much informative. Thanks.
Thank you sir
Great information, the way you explain it is clear and direct!!!
wonderful introductions. Watched it over a period of hours to absorb the wealth of information provided. Thank you for making your videos available on TH-cam.
You are very welcome! Thanks for your support, great to hear that our course videos have been so helpful.
Happy learning!
Just came across your channel it’s great
I’m have my new parents watch them because of the lack of understanding PLC’s and I’m retiring soon and they will be handling the maintenance and repairs on specialized equipment we work on
Thanks for improving my team
Great place to start learning and helps to get image how this works. Thanks
Happy to hear that Mala! Thank you.
Great video. I’m also wondering if you all could do a video on the process of Instrument Loop Checking and proper loop checking from the field device to Terminal Blocks to the PLC Input/Output cards in making sure instruments/devices are properly connected and or scaled.
Thanks for the topic suggestion, Ardent! I have gone ahead and sent this through to our creator team. Happy learning!
Always happy to watch your content!
Glad you enjoy it!
Great video learning a lot so far !!!!
Great to hear that, John! Thanks for sharing!
Thank you so much for this video.
You're very welcome!
super videos easy to learn devices .kindly detailed videos on plc ,dcs ,scada ... thank you REAL PARS TEAM
Great to hear! You are very welcome! Happy learning :).
thank u bro i have clearly understood analog with ur video
Glad to hear that, Santhosh!
Hello Sir..
All your videos are very helpful for us. Kindly make more similar detailed videos on PLC, HMI, SCADA, DCS etc..
Thankfully you all....
Thank you! Happy to hear that! I will pass your request on to our creator team.
@@realpars .. always continue to upload videos on Automation Technologies..
yes pcs7 training should start
I want to monitor one flow meter output 4-20mA....i want to see it in my PC...so what do i need?
Awesome video !! I suggest you should post videos about the programation languages of a PLC
Happy to hear! Thank you. I will pass your request on to our creator team.
Awesome channel !
I Work at a Waste water Treatment Plant in Sydney Australia, which we use all this gear here.
So goods to have such a refresher on how things work!
Have you guys thought about doing more instrumentation videos ?
Hi Ethan, That's great to hear!
I will pass your request on to our creator team.
th-cam.com/video/5nNOYlHs1Lc/w-d-xo.html
Hello RealPars,
Thank you so much for your quality explanation videos.
I have a request.
Can you make one video series for practical Industrial Project ?
In that series, u will provide the information about how exactly PLC project is approached in actual environment.
Hey Adil!
Thanks for your comment and your suggestion. I will pass this on to our course developers!
Thanks for sharing and happy learning!
Hi dear! I am learning a lot. Thanks!
You are very welcome!
Thanks a lot for these wonderful videos
Our pleasure! Happy learning
Great channel ! Very clever ! Thank !
Thank a lot, Veera!
Very thanks
Thank you so much !
You're very welcome, Kevin! Happy learning
Good job guys it looks interesting !
Thank you Younis!
Maybe you can find the PLC you need in our store: stores.ebay.com/cntop201301
Thank you for your job..
I request you to add some videos on analog input to PLC and how to program it.. please..
It's been very helpful from your videos..
I hope u will do the need
Hi Mounesh,
Thanks for your suggestion! We do have a couple of video courses on Analog Input in our course library realpars.com/, accessible for all our paid subscribers.
Happy learning!
@@realpars Hello, could you tell me in which section of your videos (lesson numbers) do you talk about analog automation? I've heard that it is at the watch and force table section where you talk about Peripheral input interface. But it would be great of you added more real life examples of analog automation process.
Thank you
great video thanks
Very good explain .... sir... 🙏
Thank you!
Great stuff about plc
Great!
This technology is bang up to date.
th-cam.com/video/5nNOYlHs1Lc/w-d-xo.html
Thank you for your channel..
You are very welcome!
Thanx a lot for these informations
You're very welcome!
Excellent video
Thanks a lot, Kenny! Happy learning!
good&lovely learning....... thanks bro
You're very welcome!
Maybe you can find the PLC you need in our store: stores.ebay.com/cntop201301
Howdy. Nice as usual.
Some discussion about measurement precision might be in order.
Let's take two pressure transmitters from the same manufacturer. One is 0 - 1 bar and the other 0 - 10 bar. Both have a precision of 0,5 %.
What does this mean ? For the first one ( 0,5 / 100 ) x 1 bar = 5 millibar. For the latter ( 0,5 / 100 ) x 10 bar = 50 millibar. The accuracy bandwidth for the first is + - 5 millibar over the whole measuring span and for the latter + - 50 millibar over the whole measuring span.
What is the accuracy bandwidth ? It is the + - standard deviation which, somewhat simplified, means that 2 measurements of 3 are inside the bandwidth.
Alright. Now the plant manager says he wants to reduce the stock of spare parts and orders the 1 bar type to be removed from the stock replenishing program. Just use the 10 bar type and multiply the reading by 10 in the PLC.
What is wrong with this approach ? Let's say we have a reading of 0,8 bar. With the original transmitter the actual value can be 805 millibar but with the replacement as much as 850 millibar. This much a deviation could ruin a production batch.
Regards.
Thank you so much...
You are very welcome. Happy learning!
Great job
Thank you! :)
Thank you
Thankfully you all.
Happy learning!
Excellent work, thanks you for your intent , your videos are very useful..
Thanks for your positive feedback, Hugo!
Very helpfull for plc working technician
Great to hear, Muhammad!
Maybe you can find the PLC you need in our store: stores.ebay.com/cntop201301
Super video lovely learning....... thanks.....Sir
Happy to hear! You're welcome
"C
Good video.
Could explain the practical example of analog inputs/output and digital inputs/outputs in distributed control system
Amazing video
Glad you think so!
wow, great explanation ! Thank u so much....
Thanks a lot, Hadiyan! Great to hear that our course videos are beneficial to you! Happy learning.
Awesome
Tq sir
I learned so much from your channel 👍👍👍👍
Glad to hear that, happy learning!
Thank you so much dear 👍👍
thanks
Perfect
Thank you!
Good information
Thank you!
your videos are awesome, if I have enough money, l would take your course.
Thanks for your support! Hope to see you join soon!
Great video, can you make videos on dry contact, wet contact, sinking & sourcing. Thanks
Hi there, Thank you! I will pass your request on to our creator team.
Please let me know how to measure the AI and AO signal on the IO modules with multimeter
Nice video..
Thank you!
Which type of cable is used to connect rtd and thermocouple with dcs?
Hi RealPar, I have a request, can you please elaborate more about different types of signals used in instrumentations.. Thanks in advance
Thanks for the topic suggestion, Athi. I will definitely go ahead and forward this to our creator team. Happy learning!
Please make a video about in siemens, pilz, ABB Safety relay wiring
Hi Sharif,
Thanks for your comment and your suggestion. I will pass this on to our course developers!
Thanks for sharing and happy learning!
I like so much
Glad to hear that, Angela!
is this video available in the paid subscription?
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Hi Realpars team!
i just watched a video on level sensor. I am very interested to know about a microwave sensor with steel rod and its controller. Actually we are using it in our organization. can you do something on it.
Hi Vijay,
Thanks for the topic suggestion, I will definitely go ahead and forward this to our creator team. Happy learning!
hi great job real pars continue like that
i hope more success in future
pls what the difference btwin FM & TM
function module and technology module
Thnx
Hey!
Thanks for your comment and your suggestion. I will pass this on to our course developers!
Thanks for sharing and happy learning!
i need a short answer if you do not mind
sorry
Thnx
Wow
Thank you for the information
You're very welcome!
I consider myself lucky that i found your channel.
We are lucky to have you here! Happy learning!
I m not afford to learn plc.....but I m learning through ur videos🙏🙏🙏
Good job! Happy to hear that you are benefiting from our videos.
Awesome video and animation. Is it possible to let me know what software are you using to build these nice animation?
Thank you! We use Adobe Premiere for our videos ;)
Information needed. How many analog outputs (maximum) can a PLC, or other additional elements control? Using as an electrical switcher.
The I/O capacity of any PLC system is limited by its memory reserved for I/O and the number of physical I/O cards that can b addressed. For example, a Siemens S7-1214c can have 51 analog points; an S7-1500 typically has 32x the I/O table memory of an S7-1200, so theoretically, it could have up to 1600 analog points. So you need to determine the number of I/O your system can handle. Even within the Siemens product line, there is a very wide range of capability.
@@realpars 👍👍👍 Thank you for your reply, the information is of great help to me! In the, hopefully, near future I will have to buy your tech for an important project. It's the only device I've found that has that capability.
GOOD
hello. im already an industrial electrician and instrument tech. i wnat to have some paper behind me for the future . do yall have a training program or do you know of one?
Hi Todd,
Thanks for your comment!
Great to hear your motivation in regard to learning PLC Programming. Our course library is specifically designed in a way where it provides all the tools needed for beginners to evolve into an advanced level through our hands-on courses.
Feel free to browse through our course library to see all the different topics we are covering. bit.ly/30AVJaR
Just to let you know, that we also have a free course on PLC Hardware bit.ly/2XnnUrF
Additionally, you will have access to our Technical Team - consisting of high ranking engineers with a lifetime of experience - who are here to help you out with any questions you might have along the way!
If you are interested, you will obtain full access to our complete course library (400+ video courses) by subscribing to either our monthly package for €22.12 a month or our yearly package for €159.28,-.
You can purchase our Certificate of Completion over learn.realpars.com/products/certificate, please bear in mind that we are able to issue your well-deserved certificate once you have completed at least 280 video courses.
Feel free to reach back out if you have any further questions.
Happy learning!
The power supply in connection is the same power supply to operate the transducer ?
Yes. Many analog sensors are 2-wire, loop-powered, meaning the 24VDC power circuit from the I/O card also powers the sensor.
Hi, Usually industrial analog sensors are multipoint calibrated to accommodate hysteresis. How can we enter those values in a Siemens Scale-X Norm-X instruction?
No. The NORM_X and SCALE_X functions are linear functions and assume only two "calibration" values: 0% and 100%. You could break up your curve into multiple linear segments, one segment between every two calibration values. Then use the NORM_X function to calculate a % of range and use the appropriate "segment's" SCALE_X function to determine your transmitter value.
Dear Real Pars Team,
I have few doubts,
1) What is meant by "Conditioned Input"?
2) What is the math behind for choosing 500 ohms in the PLC AI Circuit? I mean how we derived the load resistance as 500 ohms kindly explain it in detail with calculations?
Thanks in advance
Best Regards,
PC Raju.
Great questions! Conditioned input indicates that the input signal is converted from the native signal from the sensor, 4 - 20ma for example, to a signal that can be used by the electronics in the I/O card, which most often operates on a 1 - 5 VDC signal.
For the loop resistance, this depends on the specific analog input card, and as indicated in the video, this resistance is limited to 500 ohms. That does not mean that it is 500 ohms ion every case. For a 4 - 20ma sensor, a 250 ohm resistor is typically used. From Ohms law, V = I * R, so at 4 ma, V = 0.004A * 250 ohm = 1 VDC. At 20ma, V = 0.020 * 250 = 5 VDC.
@@realpars Thank you so much for your quick response.
please also clear this doubt, 1) how we will ensure that PLC analog input card particular channel is good(working) or not? for eg: i have connected a level transmitter (two wire) to a PLC AI specific Channel and when im trying to measure the milliamps at PLC card in series with multimeter im not getting any reading as well as it was not displayed on the HMI but while i have connected the same Level tx. to another card i have got milliamps and reading on the HMI such kind of scenario what kind of checks we will do at PLC AI card side? 2) is it ok to check DC voltage (1 to 5vdc) in parallel with multimeter while the specific channel was connected with two wire transmitter in a live loop circuit.
You can add Eng sub for each video if possible. So many people from different countries could understand the content of video esier.
Hi Bac,
Thanks for your comment!
Great to hear that, luckily, almost all our course videos provide the option to turn on English subtitles.
Happy learning!
Fantastic thank you, helped me to understand what my tradesman was telling me.
You are welcome!
can you give me some example to illustrate for student how to used plc for laboratory purposes that they will learn in actual,thank you
Thanks for your suggestion, and I will happily pass this on to our course developers as a topic suggestion.
When there is a seperate 24v dc supply, why does the negative connection from transmitter goes to the positive connection at analog digital converter and not negative?
In a 24VDC current loop (a series loop), you flow from more positive to less positive as you go from one device to another. From the power supply, you connect the (+) terminal to the most positive free terminal (+) of the transmitter. That just leaves the transmitter's (-) terminal, which is routed to the most positive free terminal on the converter (+). Then the remaining terminal, the (-) terminal on the converter goes to the remaining terminal (-) on the power supply. That is how a 24VDC series loop is connected.
can you please give basic information for BMS and CCTV system
Thanks for your suggestion, Hosam! I will happily pass this on to our course developers as a topic suggestion.
Plz, what's the difference between (1-5 volt) and 24 volt? Used in the loop
Typical loops in a PLC or DCS are powered by 24VDC. Analog loops have a 250 ohm resistor inline, which converts the 24VDC signal to a 1-5 VDC signal that is "native" to the electronics in analog input cards.
There is any videos for valves and solenoide and coil of solenoide ... Because i face everyday a troubleshooting with solenoide's coil
And if there is lesson for RTd and how can work exactly
Hi there, unfortunately, we don't have courses on this yet. I will pass your request on to our creator team.
@@realpars thank u so much
bro pls send your whatsapp no
Hello, i have a question. If we want to regulate the temperature inside a tank where the LRV is 40°C and URV is 140°C. Knowing that the output signal 4-20mA is, what will happen if the temperature drops below 40°C or rises above 140°C?
Will the transmitter send a signal or not? If yes his is this signal calculated?
Thanks
Hi Bärenstark,
Unfortunately, dropping below or rising above calibrated range has minimal effect on output. You may find d the current values slightly below 4 ma or slightly higher than 20 ma, but nothing significant. You will notice a big change if the current loop is broken.
Hope this helps!
@@realpars ok... but my question was to know if the transmitter could send let's just say 24mA for example if the temperature exceeds the range of temperature we had. For instance if the temperature rises to 165°C, knowing that the range is 40-140°c, would the transmitter send 24mA or not?
please make a vedio about pinouts
Thanks for the topic suggestion!
As i understand 4-20 mA is converted to voltage (1-5 volt) through 250 ohm or 500 ohm, .. Am I right? My inquire is why the card read voltage (1-5) instead of (4-20 ma)????
Great question! Per Ohm's Law for DC circuits, V = I x R. So for a 250 Ohm resistor, 4ma will give a value of V = 0.04A x 250 Ohm = 1 V. For 20ma --> V=5V.
The internal circuitry of an electronics board is comprised of many components, mostly comprised of transistor-based devices, like op-amps and IC's. These devices operate in the range of 1 - 5 VDC, so use of a precision 250-Ohm resistor is convenient and inexpensive.
lets see if i udnerstood this correctly. an analog signal is an actual physical signal, like a current running through a cable, while a digital signal is a signal that is processed and sent electronically?
Not quite. Both analog and digital signals pass current through a wire, tyipically at 24VDC. The difference is this: an analog signal is comprised of a current signal that varies in current (milliamps) between 0% signal and 100% signal. The value of a digital signal (probably best called a discrete signal) is either ON (24VDC) or OFF (0VDC).
What is transducer? Why it is used?
A transducer is a device that reacts to a property of a fluid (flow, temperature, pressure, level, etc.) and converts that measurement to a signal that can be used by a PLC.
@@realpars Can I say it sensor?
I want learn more about PLC but I’ can’t do it you can teach me about this all
Hi there,
Great to hear! We surely can, we have around 300+ courses in our course library. You can subscribe to our course library through this link realpars.com/ for a small monthly fee of $19.99 or $9.99 if you subscribe to a yearly plan.
Also, we have a free course one PLC Hardware that might be something you want to have a look at. realpars.vhx.tv/browse
Happy learning!
RealPars hi, after my graduation b.tech eee I worked on only electrical products & lv switchgear. Now I’m currently working as sales engineer for LV switchgear as well PLC automation. So I would like to learn about PLC ; note I’m having zero knowledge over automation, so pls. Advise me available courses
naresh212@hotmail.com
Maybe you can find the PLC you need in our store: stores.ebay.com/cntop201301
Pls made a video about the temperature compensation inside the module.
Hi there, I will pass your request on to our creator team.
I want to learn PLC logic Programing of Allen breadly or Siemens etc. I also want to learn SCADA.
How can I learn these things ?
Plzz help me . I am from India.
Hi Abhinav,
Thanks for your comment and great to hear that you are interested in learning PLC Programming.
Our course library is specifically designed to provide all the tools needed for beginners to evolve to an advanced level through our hands-on courses. Feel free to browse through our course library to see all the different topics we are covering. bit.ly/30AVJaR
Within our course library we mostly focus on Siemens, with a smaller section on Allen Bradley.
If you are interested, you will obtain full access to our complete course library (400+ video courses) by subscribing to either our monthly package for €22.12 a month or our yearly package for €159.28,-.
Additionally, you will have access to our Technical Team - consisting of high ranking engineers with a lifetime of experience - who are here to help you out with any questions you might have along the way!
Hope this helps! If I can be of any further assistance, please let me know - I’m more than happy to help!
You videos are useful.please make in Hindi language
Thanks for your comment! We currently only provide our course videos in English, you are always able to turn on the English subtitles as that might make it a bit easier for you.
Our apologies for any inconvenience!
Happy learning!
In which FC analog inputs are configured?
Analog inputs are typically configured at the I/O board level (hardware configuration). For Siemens analog cards, the analog inputs are scaled from 0 to 27648 counts (h6C00). The analog input can then be scaled with FC100 (Scale2Real) in STEP7 or by using the SCALE function in TIA Portal.
@@realpars Thank you 😍
can you help me to get demo version s7 300
Hi Ashenafi,
Thanks for your comment!
We sell a variety of software and hardware on our online store, including the STEP7.300 marketplace.realpars.com/
Feel free to have a look around, let us know if you have any questions
how to connect pressure transmitter to siemens logo controller 12/24rc
You will need to add a Logo AM2 module to your basic module. The Logo AM2 module supports 2 analog inputs. When connecting to the module, use 24VDC power and select 24VDC on the module (slide switch). For a 4-20ma sensor, for channel 1, connect (+) to I1 with the corresponding (-) wire connected to M1. Connect the shield to X11. For channel 2, connect to I2/M2/X11.
@@scottsommer6480 thank you
Are the voltages ac or dc??
Hi there,
Thank you for your question! The answer is DC voltage.
The 4-20mA output signal is an analog output signal commonly used in sensors. It is typically powered by DC voltage ranging from 8-32 VDC, which is widely available commercially. Here is a link for your learning.
core-sensors.com/wiring/4-20ma/#:~:text=The%204%2D20mA%20output%20signal,which%20are%20widely%20available%20commercially.
Happy learning!
@@realpars thanks!
Real pars, I have a doubt. Why plc generally has less analogue input modules(compared to digital)?
Hi there,
Thank you for your question. Analog input/output channels consume a greater amount of memory compared to digital channels. The memory requirements for your PLC will largely depend on your specific needs, and it's worth noting that using analog channels can be more resource-intensive and potentially costly.
To put it into perspective, a single PLC analog channel typically occupies 16 bits of memory, whereas a digital input/output channel only uses one bit out of those 16. This means that you can have a greater number of digital I/O channels to work with in comparison to analog channels.
Happy learning!
@@realpars Thank you 😊
Please provide the Analog Output also
Hi Mr. I wnat to download software do you have a software for free s7 Micro win.
Hi Vecheka, I have two links through which you can download different versions of STEP7
sie.ag/2eH6GEM sie.ag/2Jt80F0 Hope this helps! Happy learning :)
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Maybe you can find the PLC you need in our store: stores.ebay.com/cntop201301
Why there are 3 wired and 4 wired connections
why I can't measure resistance between 2 wires ?
I think, U should make the video with more details & in a more simple way
Thanks for sharing your feedback, much appreciated!
dose any one have purchased tutorial videos from RealPars ?? i need it please inform me
Hi Sayed,
Our course library is subscription based, you can obtain access to our whole course library (400+ video courses) for as long as you are subscribed. We also offer a monthly subscription option, that might be interesting for you. You can have a closer look over here realpars.com/.
If you have any other questions, please feel free to send them my way :).
Happy learning!
Can you give one example program for ai and ao sir
Hi there, Controlling Pressure and Flow of liquid
@@realpars Ok sir
AI means analog input ( like the weight of something which can have a wide range like 0,10,30,73,88,92) and AO means analog output (like flow of liquid which can also be in a wide range is set by the output signal from the controller).
sir I need online training, please help me,
Great to hear that, Mehedi!
We have a course library filled with online courses on PLC Programming.
Our course library is specifically designed to provide all the tools needed for beginners to evolve to an advanced level through our hands-on courses. Feel free to browse through our course library to see all the different topics we are covering learn.realpars.com/
If you are interested, you will obtain full access to our complete course library (500+ video courses) by subscribing to either our monthly package for €24.99 a month or our yearly package for €179.99,-. Additionally, you will have access to our Technical Team - consisting of high-ranking engineers with a lifetime of experience - who are here to help you out with any questions you might have along the way!
Hope this helps! If I can be of any further assistance, please let me know - I’m more than happy to help!
@@realpars thanks a lot for replay.I will online course as soon as possible
I need burner ladder and hmi program
Why is it called an analog input if the input signal is 4-20 mA DC?
The definition of analog is: "relating to or using signals or information represented by a continuously variable physical quantity such as spatial position, voltage, etc.". In this context, an analog input is continuously variable signal between 4 - 20ma. This signal as transmitted, is typically decoded as a 14-bit or 16-bit signal, which allows the current to be decoded to 16384 discrete increments. For a 16-bit analog card, 1 part in 65536.
@@realpars Thank you for your response. What I don’t understand is if the signal is analog that makes it by definition not digital right? So why do I measure 4-20 mA on the DC setting on a device that is called “analog input”? Perhaps “analog current” does not mean the same thing as “alternating current”?