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  1. RS485 COmmunication

    Hi all, i am looking for a solution to connect 7 plc with a single scada. is it possible according to my topology diagram ?   Kindly make me suggestion and if you have any information regarding the solution then share .   Thanks in advance. 
  2. MX2 Modbus doubt

    Hi there! I'm programming a CP1L-E CPU to control 3 3G3MX2 inverters via Modbus. It got some things right, like the INV002_Refresh_X31 block and its parameters. The thing is, I also want to read some parameters from the inverter using the INV206_ReadParameter block. My doubt is, do I need to be careful so both blocks don't execute at the same time and use the serial port at the same time? Is it better to use one INV206_ReadParameter block for each parameter I want to read? Thanks in advance!
  3. Good Morning,   My name is Joseph Rhodes, I work as an electronic technician for the City of Tuscaloosa at the wastewater treatment plant. I work to keep the plant up and running as well as 64 lift stations spread out around Tuscaloosa, Alabama. A majority of our lift stations utilize Verizon Cell Modems, RV50s to be exact. It's rather easy connecting remotely to these lift stations as I can configure a driver as an ethernet / ip driver then associate an IP of that lift station (ex. 10.181.3.104 is lift station 104, 10.181.3.105 is lift station 105, etc). However, for the lift stations that do not utilize cell modems. We use GE MDS 9710 and 9810 radios. It is these lift stations that I have yet to figure out a way to connect remotely to the LS RTU PLC. All of our lift stations use Allen Bradley MicroLogix 1200s or 1400s. These lift stations that use the MDS radios communicate information to water tanks then that information is sent back through other channels. I was wondering is there a way to associate these lift stations on RSLinx that use GE MDS radios ?   
  4. GOT2000 as MODBUS TCP slave

    I have this setup: FX3G CPU connected to GT2103 through RS422 (CH1). GT2103's ethernet port connected to LAN and set up as modbus TCP slave (CH2). I want to read/write PLC word devices using a modbus TCP client, from a PC. The HMI is acting as a gateway between PLC and PC. I used the Device Data Transfer function to send PLC's D register values to GT's internal GD registers. D0....D9 ==>  GD0....GD9 After some tries, I get valid response from the modbus slave. Reading the holding registers 0....9 (40001....40009), I get only zero values. Those registers can be written back with different values, correctly. I'm sure I didn't understand correctly the modbus address mapping to GT's internal memory. Can anybody help me? Thank you.
  5. Hi all, I am trying to communicate KEPServerEX with FX3GE vis UDP protocol. I have tried but unable to get data on Kepserver. While configuring communication properties in PLC we have configured PLC IP, PLC Port, Destination IP, but unable to find correct Destination Port. Although we tried various port nos like 49320, 57412, 57512, 56233, 1025, 32402, 57212, 57012, 57612, 57812 but there was bad quality data using UDP For same PLC using TCP/IP we were able to read all tags properly. This change in communication protocol is required as there are some PLCs whose communication port drops after few days of connection establishment (no error logged; can be re established with just restart). Someone from Mitsubishi said to try communication via UDP as it continuously fetch data regardless of kind of response received. If anybody has tried or have any solution, please do share.   Thanks
  6. Hello everyone    I am working on modbus TCP protocols to communicate between SEW drive and Omron PLC CP1L-EM. I am following modbus TCP function block from Omron, But i have updated that block because of is not fit to SEW modbus communication. Currently, I am sending a control work to SEW but I am getting error on Modbus TCP from SEW drive, which is invalid data. So I am looking your help is you work with SEW drive before and communicate over modbus, then please let me know how to make a data string for read and write (SEW Drive function 23). I am using 3PD data structure.    Thank you
  7. Hello friends, I am an Omron PLC user, but have never used modbus before. I have to connect an Omron CP1L-m to Beckhoff bk7300 via modbus serial gateway. 2-wire RS-485 connection (CP1W-CIF11). I have seen an easy to use Modbus RTU master for CP1L CP1H CJ1 CJ2 CS1 but the examples are not for dual port CP1L-m. If I change the PLC model "CP1HCP1LModbusDualPort" to "CP1L-M", the compiler tells me a lot of warnings about variable types. Is Modbus RTU Master easy to use for CP1L CP1H CJ1 CJ2 CS1 compatible with CP1L-M dual port (port 2)? I have tried to use it but it didn't work, error 02, illegal function code. Somebody could help me? Thank you Enric
  8. Mitsubishi Fx2n Modbus rtu vfd

    Hello everyone, may you all bless with the best. Can anyone please help me on connecting and programming In Modbus rtu INVT CHF-100A vfd with FX2n having rs485-bd moblue. I want to connect 11 vfd and one fx2n plc also 
  9. Mitsubishi Fx2n Modbus rtu vfd

    Hello everyone, may you all bless with the best. Can anyone please help me on connecting and programming In Modbus rtu INVT CHF-100A vfd with FX2n having rs485-bd module. I want to connect 11 vfd and one fx2n plc also .
  10. Mitsubishi Fx2n Modbus rtu vfd

    Hello everyone, may you all bless with the best. Can anyone please help me on connecting and programming In Modbus rtu INVT CHF-100A vfd with FX2n having rs485-bd module. I want to connect 11 vfd and one fx2n plc also 
  11. Hi, I managed to communicate a Kinco HMI with a Xinje PLC (XC3-48R) using RS-232. Also, I've established connections between the both equipment and my personal PC, for programming purposes. Currently the uploading and downloading, PLC bits reading and writing happens normally. But, when I disconnect any of the equipment from the PC, (HMI or PLC), the communication is lost between the PLC and HMI.  How can I solve this and, remove my PC from the network by making the HMI master and PLC slave ?    The software I use for programming is, (XCP Pro, Kinco HMIware)  
  12. Hey all,  So I am looking for some assistance because I am not understanding how the tags on an HMI and within a PLC are linked. There are no 'physical' buttons, just what is on the HMI. It is controlling a chiller. Communicates over Modbus TCP/IP. The PLC is an IDEC. I have some-what worked out how other tags are working when they are words being passed back and forth, but this one has me stumped. I've attached a few screenshots for referral. It looks like the run and unload buttons for the chiller are a single bit/BOOL toggle (but the chiller running latches itself in the PLC when the chiller starts to run). The stop buttons appears to be a parent for the single bit/BOOLs and when it is pressed it resets them all both on the HMI side and within the PLC side.  
  13. Hi there, I have a controller NX1P2-1140DT. I want to control a VFD with modbus serial communication. Can someone help me start from scratch ?
  14. FX3GE Communication issue

    Hi all, There's an issue I am facing for multiple FX3GE PLCs in a plant. Communication breaks between a PLC and OPC server. PLCs after few days (4-10) does not respond over ethernet. No ping response is received over network as well as when checked one to one direct connection. If I restart the PLC the connection is resumed and again after some days it goes down. Error LED on ethernet port does not glow red (no indication for error). If anybody has faced similar issue and has resolved, please share.
  15. CX-8190-Modbus Srv

    Hey guys, I am trying to communicate between a Beckhoff CX-8190 & a third party fieldbus module that supports Modbus TCP, now I am able to write/read to the fieldbus when twincat is running on the local machine (laptop), but when ever I connect to the device and run the same function block it doesn't write nor read to the fieldbus. I am assuming that the modbus server has something to do with it, so is there a way I can install it to the plc ?
  16. KINCO PLC as MODBUS RTU slave

    Hello to everyone. I hope you are doing well. I'm trying to establish a communication between my PC and my KINCO PLC. The manual states it supports MODBUS RTU protocol, so I downloaded two different Modbus Master simulator I found out: Multiway from OMRON and qModMaster. None of them seem to work properly. I attached some pictures of the messages I get. https://ibb.co/f1mCSNt Multiway message https://ibb.co/bP5cX1t qModMaster message I include the configuration of the communication parameters. https://ibb.co/nMty8D9 PLC parameters https://ibb.co/6RTqVfC Multiway parameters https://ibb.co/N1XTccd qModMaster parameters According to the manual, in order to play the role of Modbus master with the PLC it's necessary to configure some instruction blocks (I'm programming in ladder). However, I could not find any block to configure as Modbus slave. I don't know what else I can do. I'm in trouble with this task. Am I making some mistake? Thanks for your attention.  Kind regards!
  17. Serial communication with KINCO PLC

    Hello to everyone. Nice to meet you all. I am programming a KINCO PLC model HP043-20DT using ladder on KINCO BUILDER. I need to establish a serial communication with my PC. The PLC has a RS485 port which I adapted it to USB to connect with my PC. The PLC allows, at least, two ways to establish serial communication: MODBUS or free-protocol. I've read the software manual and tried to reproduce the examples it provides using the instruction blocks for MODBUS (MBUSR and MBUSW) and free-protocol (XMT and RCV) communications. However, I could not receive the data on the PLC. I could effectively transmit data with XMT from the PLC to the PC and I could verify through a tool called Access Port. In relation to MODBUS, I am using a simulation tool called Multiway from OMRON, however, I get no response from the PLC. If any of you have some experience with this software or this device, I would like to ask you how could I solve the problem. Thank you for your attention. Kind regards.
  18. Memory registers on KINCO PLC

    Hello to everyone. I hope you are doing well. I have a KINCO PLC HP043-20DT. I'm communicating through free-protocol instructions XMT and RCV. The manual states that memory registers SMB86, SMB186 and SMB286 contain information about the state of the reception instruction. I would like to ask if any of you know of the existence of an analog register but with respect to the transmission instruction, instead of the reception. The manual does not indicate it and I could not find any information online. I've sended an email to the manufacturer but, until now, I have not receive any answer. Otherwise, how could I search for this information? I tried through the manual providede by the manufacturer, but maybe there is other way. I would appreciate any information. Thank you so much. Kind regards.
  19. IEEE-754 Floating Point

    Hi, Is there a simple way to convert hex value of IEEE 754 to real value in gx works 3 Regards, Ramkumar  
  20. Hi everyone, I'm new here. Thank you all in advance for the help you can give me. I have one machine with PLC Omron NJ101-9000, and this is Server in the Modbus communication. In the attachments, you can find the function block I used to communicate with 1 client. This work OK and I don't have problems, but I need to communicate with 2 clients at the same time. This block only admits one connection at a time. How I can connect 2 at a time? If I create 2 of these blocks, does each client need to connect to a different port? Do I need "open" this port in PLC configuration?   Thanks!
  21. Hardware IQ-F connected via Modbus TCP on the NZ2FT-MT works Fine with normal IO. Now i want to run the NZ2FT-C24 with an modbus RTU protocol, i'm planning to make this. Anyone having an example for the NZ2FT-C24, what can help me?
  22. Hardware IQ-F connected via Modbus TCP on the NZ2FT-MT works Fine with normal IO. Now i want to run the NZ2FT-C24 with an modbus RTU protocol, i'm planning to make this. Anyone having an example for the NZ2FT-C24, what can help me?
  23. Hi. I have this project where we read out data from temp sensors and vaccuum stuff. We use Pfeiffer vaccum cpt 200 for the vaccuum, and we create a frame to send to the modbus unit to pull a value from example '306'. With all the current items we pull data, all the values are only updated every 5 seconds, is there a way to perhaps pull several frame/addresses in one request per device? Current codes we read, some are in sequence of each others, but more has a bit of gap like 00, 02, 306, 307, 398, 330 and so on.    
  24. I am trying to create a simple `Hello World` Modbus TCP/IP program using Twincat3 and virtual PLC (PLC running locally on my computer).   I have set up a LabVIEW Modbus TCP/IP master + slave program (both of which are working see screenshots below).  I can send data between LabVIEW's master and slave programs. And also read the data from Python script (so I know for sure they are all working).  Now I have tried to create a Twincat3 program to set some registers using Beckhoff example What I have tried:  - I have tried changing the ipAddr parameter to: 'localhost', '192.168.88.1', '192.168.88.126'  - Also I have tried the nUnitID set to: 0, 1, 16#FF (16#FF as specified by Beckhoff docs) This is my Beckhoff code:     PROGRAM MAIN     VAR         ipAddr         : STRING(15) := '192.168.88.1'; //Tried also 192.168.88.126 and 192.168.88.1 'localhost'         M0 AT %MB0     : ARRAY [0..3] OF WORD;         nValue         : ARRAY [0..3] OF WORD;         fbWriteRegs : FB_MBWriteRegs;         bWriteRegs     : BOOL;     END_VAR           IF NOT bWriteRegs THEN         nValue[0]                := nValue[0]+1;         nValue[1]                := nValue[1]+1;         nValue[2]                := nValue[2]+1;         nValue[3]                := nValue[3]+1;                  bWriteRegs                 := TRUE;                  fbWriteRegs.sIPAddr     := ipAddr;         fbWriteRegs.nTCPPort     := 502;         fbWriteRegs.nUnitID        := 16#FF;             //Tried setting this to 0,1 and it also and didnt work ...         fbWriteRegs.nQuantity     := 4;         fbWriteRegs.nMBAddr     := 16#3000;         //Tried: 16#3000, 0, 1         fbWriteRegs.cbLength     := SIZEOF(nValue);         fbWriteRegs.pSrcAddr     := ADR(nValue);         fbWriteRegs.tTimeout     := T#5S;         fbWriteRegs                (bExecute:=TRUE);     ELSE                  IF NOT fbWriteRegs.bBUSY THEN             bWriteRegs             :=FALSE;             fbWriteRegs            (bExecute:=FALSE);         END_IF                  fbWriteRegs                (bExecute:=FALSE);     END_IF  What should I change in my code in order to make this example work? Thank you in advance for any support!   Info about LabVIEW programs:  I am using the Modbus TCP Master / Slave examples  The IP address is set to localhost and the port to 502 (which should match the IP address in my Beckhoff code)  I am 100% sure it works because I have also tried connecting to this program via Python script. Picture of my LabVIEW programs:
  25. Hello, I am using Easymodbus library to Communicate with Modicon TM218 PLC. Reading and Writing of Holding Registers working fine. But coming to writing of single bit in data register i am facing Problem. Need to know how we find coil address of a data register. e.g I have to write bit 1 to MW70.1 address. How we do that. Right now i am reading complete MW70 Register and Manipulating it using bit manipulation techniques and again Writing using Write single Register Function. It's working but some times because of reading problem it writes some garbage values. At that time complete system effecting.    Please provide me any solution. Thanks in Advance.