Search the Community

Showing results for tags 'logic'.

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Found 42 results

  1. Emerson 90-30

    I'm working with Emerson 90-30 on proficy machine edition and I'm trying to use a string variable to display words on a graphical panel in target 2 but withing the code itself on target one I cant seem to understand how the reference address works? can some one explain how string variables function and how to use them?
  2. As the industry of plc and scada softwares continue to integrate more and more programming languages into their IDE, what is the most common language that should be learned by controls engineers (excluding Ladder Logic)?  I mainly use Python and VB for scripting but I am curious what languages other SCADA and PLC programming environments use. Should I be sticking to a specific language and learning it well or just know a little bit of them all? Let me know your thoughts!!
  3. Newbie in the field of Automation here! I have a waste water project that requires operating 6 pumps to empty a sump. The water level in the sump is being monitored by an analog ultrasonic sensor. The analog range is divided into 5 levels; level 1 being the lowest and level 5 being the highest. The way the pumps operate is analogous to the water level, i.e., 5 pumps will run at level 5, 4 pumps will run at level 4, 3 at level 3, 2 at level 2, and only 1 pump will run at level 1. The sixth pump is used to run the pumps sequentially and that's where I need help. Basically, the pumps can not be assigned to a certain water level as this would result in the pumps at the lower level run way more as compared to the pumps assigned to higher levels. The pumps need to alternate so as to keep the running hours of each comparable. Another requirement is that say if pump 1 turns on due to water level rise and then turns off due to water level fall, and again if the water level rises, then the next pump should start instead of pump 1, and so on for the rest of the pumps. Also, if one pump goes on some kind of fault, the 6th pump comes in and runs in its stead until the fault is reset. I'm trying to come up with a ladder program to make all this happen but hoped that I could find some help online. I feel like this is a common project and there should be someone that can give me the proper solution. With thanks, Aafaq.
  4. What are the types of fuzzy logic syatems and it's applications? Is the fuzzy systems based on the vague value or real values? What are the real time applications of fuzzy logic. I am writing a thesis at best essay writing services on fuzzy logic and it's applications.
  5. Hey, (Programming a M224 with Machine Expert Basic) I'd like to get some input from you guys about a logical task: I have 8 contactors controlled by my PLC outputs, they heat a water boiler. throughout my operation, I require a different amount of heaters (I could move between 1-8 heaters in a single operation) I would like to scramble what contactors I put in use every time I start an operation, in order to not constantly use the same heating elements and wear specific ones out. For example, in the first stage of heating I will use contactor #1, next time I start the operation I would like to use contactor #2 and so on.. How would you approach this problem? SBR? Timers? Thanks
  6. Hi, Could anyone help me out on how to extract the digits present in a string in sysmac studio... Thanks in advance !!!
  7. Hello Everyone, I am writing one logic and need some help regarding that logic.   CURRENT LOGIC -  -There are two timers TON_1 and TON_2. -TON_1 timer will start as soon as PLC turns on. -After the done bit of TON_1 timer, the TON_2 timer goes on. -After the done bit of TON_2 timer, again the TON_1 timer will start. -This logic cycle will run continuously, both timers will run turn by turn. Code (Codesys/Schneider Eco Structure Machine Expert)- PROGRAM POU_1 VAR      TON_1: TON;     TON_2: TON; END_VAR TON_1(IN:=(NOT(TON_2.Q)) , PT:= T#100S); TON_2(IN:=(TON_1.Q) AND (NOT(TON_2.Q)) , PT:= T#20S);   Actual Requirement -  -There is a BOOL tag. -If the BOOL tag gets high during the TON_1 running, the logic should move to the TON_2 immediately. -If the BOOL tag does not get high during the TON_1 running, the logic should move to the TON_2 after completion of TON_1. -after the completion of TON_2, again restart TON_1. -Logic Runs continuously in a cyclic mode.   Give me your valuable idea to fulfill the logic requirement.
  8. Hello everyone, I am new to PLC programming and will start working on Allen Bradley PLC. I have an experience in computer programming languages. Will learning ladder logic be a better option or starting with structured text as i have some knowledge about the syntax and programming of structured text?
  9. So I have a plc program where most of the outputs are based on a counter that goes from 0 to 1000. The counter speed is adjustable and is generally set to run through a full cycle (count from 0 to 1000) anywhere between 0.5 to 2 seconds. The problem is, when I try to energize an output by using an EQU instruction, it will almost always skip the count because the scan time is not fast enough. I've been using a LIM instruction which has been working, but its not quite as accurate as it needs to be. I switched the counter logic to be continuous to try to make it faster which made it almost perfectly accurate... But only in the continuous task; it made the other periodic task significantly less accurate. I was curious if any of you had any tips on how to remedy this or just general help. I am still relatively new to PLCs and ladder logic so any advice would be awesome, Thanks in advance! Edit: The purpose of the counter is to cycle through from 0 to 1000 over and over again. My outputs actuate during a certain interval within this cycle (For example I would say actuate from 300 to 800 and it would stop and end once it hit those values via an EQU or LIM instruction). I wrote the logic as follows: First I calculate how many cycles per minute I want to perform, using that value I calculate how many times I want to increment my counter per millisecond. Then a timer is given a preset of the total cycle time. While that timer is running I continuously multiply the timer's accumulated value by the "cycle count per millisecond" that I calculated earlier; the resulting value is the current count that all my outputs are based on... Hopefully that makes sense, I know it's not the best but I could not figure out a better way of doing it and I know rounding is certainly making the accuracy worse. My hardware is: Allen Bradely PLC (5069 l306erms2), 5069-ob16, 5069-ib16, and a Kinetix 5500s2 Driver for my motor(s)
  10. Hi there, I am fairly new to programming serial communications, especially with Mitsubishi PLCs. Can someone walk me through in ladder logic how to bring in ASCII to the PLC, store the data in the data registers. Then send the data out to another PC once an 'X' input is satisfied? ASCII code would go like the following: C2,0,1,123,2,ABC,3,456,CR
  11. We have been working with PLCs for long time. We used to develop PLC logic, partly test it on an emulator and test the rest on the partly energised equipment. From time to time working with computer software development (C# and JavaScript) I was always looking for something similar to unit testing in the PLC world. As I couldn't find anything at that time I've started developing own automated testing tool. Now we use this tool, which basically simulates PLC inputs in defined actions and checks expected behaviour of internal tags or/and PLC outputs. If it behaved the way we expected, it's PASS, otherwise it's FAIL. We break complex logic into small parts and create unit tests for it. By creating more of these unit tests we can test PLC logic of any complexity. The software called PLC Logic Prover and it's free at https://www.controlx.io Recently, I've been told that there is no point to develop anything new if there are already great tools on the market. Honestly, I didn't do proper research earlier, so I'm here asking the experts. What do you use to test PLC logic? What automated testing tools do you use? Is it using IO simulation or it can test logic by other means? Your replies are appreciated. Thanks, Alex
  12. A little background information here, I am trying to create a moving average so I accomplished it with the code (imaged attached) The problem i am having is the AVE instruction error bit goes true. it leaved me with a result of 1.#QAN  I did some googling and it said this is typically done when dividing by zero?? so i added a NEQ to 0 prior to loading the array. then it happened again. so i put the error bit in front of the FFL so it will stop loading the array when i get the error bit so i can see what values are in the array when it errors out. Has anyone else had this issue and what could you do to resolve it? I haven't had any luck find something that points me in the right direction. Thanks in advance for your help.
  13. Hi, I've been having a problem with my Schneider setup, and I can't seem to figure out the problem. I'm using Machine Expert Logic Builder and Vijeo 6.2, and I can't seem to download to my PLC. I can download to my HMI just fine, but my HMI comes back with the message as mentioned in the title. Also when I perform a full download, machine expert comes up with the message "Could not connect to the device for item "xx", selected target system "PLC name" is different from the connected device "HMI name". The weirdest thing is that machine expert shows my PLC just fine, but doesn't show my HMI. I have no idea what to do, as I feel like I've tried everything. The IP range is fine, subnet is fine. The driver in IO manager in Vijeo has the PLC nodename in it, so that shouldn't be the problem either. Does anyone know what to do in a situation like this? Thank you in advance!
  14. Please could you assist with the software required to download data tables from 4 off DIRIS A10 Multifunction Meters into TM221CE40R Logic Controller via TMC2SL1 Comms Cartridge using Modbus Protocol over RS485. I have downloaded the Modbus tables from Socomec but not sure how to get these into the PLC. I would really appreciate your help in achieving this. I am using EcoStruxure Machine Expert - Basic to program the PLC & DAQ Factory Developer Release for my Touchscreen. Link to Socomec Modbus tables: https://www.socomec.com/files/live/sites/systemsite/files/SCP/6_gestion_energie/diris/diris_a10/DIRIS-A-10_COMMUNICATION-TABLE_2018-01_DCG01013_MULTI.html#General
  15. Control Panel

    Is it possible to view the values / states of all inputs, outputs and workbits (e.g. 64.00 through 64.15 on Omron CQM1 PLC) on a single screen or control panel within CX-Programmer software?  I'm trying to troubleshoot some ladder logic that I wrote and need to know the values of 5 or 6 inputs/outputs/workbits simultaneously.  Having to scroll up and down through my ladder logic repeatedly does not work well with code that changes state every 5-10 seconds or so. Any help is welcome.
  16. Q03UDVCPU

    I am new with PLC's and I am learning how to work with GX Works 2. I have two questions, 1st Question: Using a Q series PLC (Q03UDVCPU) Is it possible to convert the language of a project from ladder logic to structured text? 2nd Question: If I read a project from a PLC why is it always ladder logic? Is there any way to read out structured text?
  17. Hi I'm looking for Ladder Logic code that I could use for a plastic injection molding machine.  I am willing to purchase and/or modify existing code to meet our specifications.  We have lost the Ladder Logic out of the TI/Siemens Controller on our Newbury 100 Plastic Machine so we're looking at replacing both the PLC and the HMI interface with an Automation Direct Controller.  We have the HMI Basic Code for the Newbury but not the ladder.  I've pasted the manual below for our machine.  Any assistance would be much appreicated.  The manual was too large for me to post but I've posted a document with information about how we intend to upgrade which has a little information about the machine also. Newbury 100 upgrade logging.docx
  18. Hello! I have a project where I need to use Allen Bradley PLC, it might be one of CompactLogic series. In scope of the project I need to transfer few real values to DirectLogic PLC that installed on customer side. DirectLogic PLC has installed ethernet card that support Modbus TCP, TCP/IP and UDP/IP protocols as it says on automationdirect website. I start looking for Allen Bradley PLC that support Modbus TCP or TCP/UDP protocol and did find clear information. Could you help me to find out a way how I can pass the data to directlogic PLC from CompactLogic?   Thank you in advance!   Regards, Scotty
  19. Hi..  someone please help me.. i'm working in omron CS1H-H CPU67 PLC. My struggle is I/O in one particular rung is not getting updated.  Note: the rung is consist of a P_On flag followed by a FB ; all I/O to the FB were correctly assigned. but the inputs inside the FB instance are not getting updated so that the output not updated. can anyone please help me....????   sorry for my poor english... thanks in advance.
  20. I need to run 4 exactly same devices with 4 different controllers. The logic for them would be exactly the same but the IPs and controller names would be different. Is there a way to do it using 1 project file? Basically whenever download is done the logic would be downloaded but the controller name/IP would be left unchanged. They will be connected to the same network so the IPs must be different. I am using 1769-L32E for these and all racks are set up exactly the same. Any ideas?
  21. Hi Everyone, I'm working on my first PLC program and I have gotten my hands on some ladder logic I'm trying to duplicate. I'm using SoMachine 4.1 and have started a new Ladder Logic diagram POU. I'm curious on how do I create internal contacts. EXAMPLE: 24v--------l START BUTTON l----------------( COIL A)----- --------------l COIL A CONTACT 1; attached to a real output, solenoid valvel-------------l COIL A INTERNAL CONTACT TO CLOSE l---------------- Are there standards for numbering and labeling? I'm seeing L and U inside coil contacts. Does this have an underlying meaning according to standard? Is there a RTO function inside SoMachine 4.1    
  22. Hi everyone, I'm a newbie in the ladder logic programming languages. For my thesis project I've to develop a scenario but I'm stuck with the creation of a socket connection from the Modicon M340 PLC to a server for transfer continuous data given from sensors or similar. Does anyone have a sample program that could have such a functionality so that I can change it based on my needs? Thanks in advice for any further reply!
  23. Hello, I am currently working on programming my first sortation system.  Attached is a blue print of the in feed conveyors and their loadout lines.  As boxes merge together they will be scanned by the barcode scanner.  From there we will be told which lane each box must go down, from the WCS.   My question is, without encoders, what would be the best way to control this system? Counting the packages as they pass through the photoeye? Or setting timers?   Thanks, James Sorting Conveyor Layout.pdf
  24. PLC SIMULATORS (LADDER LOGIC)

    CAN SOMEONE PLEASE SUGGEST ME ONE OF THE BEST ONLINE LADDER LOGIC SIMULATOR OR SIMULATOR SOFTWARE FOR PRACTICING AND DEVELOPING LADDER LOGIC SKILLS.??