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Showing results for tags 'Modbus'.
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Hello, I now have a few unitronics PLC's on site, I am getting more familiar with them but still fairly new. I have an application where the PLC talks to a cobot over modbus, everthing works great, never had any problems with it. This morning i was asked if I could display the "current program" running on the cobot on the unitronics HMI. I thought it would be as easy as just reading a string data type.. I'm now thinking that to read the string, I read each interger in addresses 7701-7799 assuming that the numbers are Ascii code(manual doesnt say) then concatenate them to get the string. Does anyone have experience of reading strings from modbus slaves??
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Hello I wrote a test program to test our Modus Slave units. The Unitronics UPS-104-B10 is a master talking to 6 of our slaves. I've written test programs on the Unitronics for the following BAUDRATES 2400, 4800, 9600, 19200, 38400, 57600. All the Baudrates function correctly except 2400. I've even slowed down the trigger timer to allow a 2-second delay between Aperiodic Triggers. My SLave device reacts to all messages and replies correctly, The T3.5 spacing and T1,5 spacing are also correct (monitored on sniffer) I also verified the messages on the UART side (Before RS485). The CRC values are correct. The problem is that when the PLC does a Read Holding, the value returned from the slave does not reflect in the TAG in the PLC. It stays zero. Is there a trick to use 2400 BAUD? Marinus -
Hi, I searched the forum, but didn't found something to help me. I have a unistream, connected with +-12 modbus gateway's (via TCP/IP). when I look after I downloaded my program to the PLC, then I see that some modbus slaves are not connected... Is there a limit on how many remote slaves IP's ?
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Hi, I´m trying to read the preset and current value of TD10 from a VISION 350-35-TR34 using a UNISTREAM US5-B10-B1. From the address table I got that the address are 6910 (preset value) and 7310(current value) To read those values I did as follow: Where EQUIP1.t EST PRESET and EQUIP1.t EST CURRENT are INT32 variables. All other register reading works fine but cant make timer reading work, always get 0 value. Any advice or help you could give me I will appreciate. Thanks in advance.
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Hello, I've recently acquired the UCR-ST-B8 router from Unitronics. The set-up was easy but it won't communicate with other devices. My goal is that the router is connected to a PLC through a direct ethernet cable and that the PLC can read the status of the router, effectivly making the router a slave of the PLC. I also want to recieve SMS messages on the router and the PLC to read those messages. *Note I did change the IP from 192.168.1.1 to 192.168.0.1 With a cable in LAN 1 of the router and the other end in a laptop we can connect to the webUI. Here (Services-->Modbus) I've configured the router as a modbusTCP slave and did save the settings. After this I close the webUI and connect to the router using QModMaster (https://sourceforge.net/projects/qmodmaster/). With this program I should be able to read the registers of the router. (I know this works as I've used it before) But when I try to read the registers it doesn't get a return signal. After this I've tried it using a PLC. But I am not really familliar with the Unilogic enviroment so I'm having a bit of trouble setting it up. As stated earlyer I want to read the data from the router and recieve SMS messages from the router and read those using the PLC. Would I need to setup the router as a router or as a modem in the Unilogic enviroment? Further if I set it up as a router would I need to take extra steps to read out the UCR-ST-B8 or should I be able to read all the data immediately? So the questions I have are: How do I read out the router? What settings need to be configured. Is it possible to read the data using a PLC? I'm using a USC-B5-T24 and how would I do that. Should I use ModbusTCP or Modbus RTU rs485?
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So i am currently looking in to the possibility off sending strings (probably between 20 and 32 characters) to a v560 plc over modbus TCP. The purpose of the string is product name/version that is going to be produced on the machine where the v560 is installed. So the operator can easily sees if the right parameters are loaded. currently we do this with a 7 to 10 digit number but a mistake is easily made. How i am thinking of achieving this is by converting the string to ASCII and writing it to 16 integers. Then in theory i could use ASCII string variable to display the name on the HMI. For the moment i dont see any problems with the setup, but before i start writing the program i thought i might be smart to ask around here for other opinions. maybe there is a smarter way to do this? -
Hello friends.I am using a PLC communicating with an UAC CB 01RS4. What I want to achieve is an meter MODBUS measuring the volt and amp value of a load, connected to a PLC via Modbus, this PLC is connected to a computer via ethernet.I managed to establish communication but didn't suceed. Indeed, All attempted sessions are fails and the status is 3 - Connection exists, but there is an error in the MODBUS commands. I have added the MODBUS module to the PLC on UniLogic, and all informations (Modbus panel, baud rate, data bit....) are correct. Then I've added a Master -> 'registers periodic' -> the modbus communication is the UAC-CB-RS4 and the adress is 5000 (which is the adress register of the Voltage measurement content (for the automate). I also tried to add a slave but still I have the same errors. If you have any clue on why I have a connection but the MODBUS command has errors, please tell me 😀. Thank you very much !! -
Hello to all, We are in project which requires that operator from one place, one touchscreen, controls (start-stop, change freqencies etc.) of 36 converyors. All conveyor control same VFD model Danfoss VLT 5000 (software version 3.6). We are using V1210 vision PLC with two RS485 ports. We know that VFD-s are pretty old, and we also do not have much experience with Modbus (RS485)communication. We would ask for advice, project sample, anything that can help if anyone had some experience with Modbus comunication with this type of VFD. In attachment , sample of project where we used RS 485 to control Yaskawa GA 500 VFD, can it function in same way with VLT 5000? We also cannot find adequate documentation about holding registers for this VLT 5000 VFD. Thank you in advance for every help, Best regards. V1210 to VFD VLT 500 with RS485.vlp
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I am working on a project that has a single unistream PLC with 11 Samba PLC as slaves. The slaves are in every way identical except of course for there address and name. I have made the current setup with arrays for the data that i am reading and writing, For example: valve_status[0-10] which contains the status of particular valve from all of the slaves or vent_start[0-10] which i can manually start a fan on all the slaves. Now for my question, i have to expand the current program and i have to exchange more data between the slaves which i can do manually. In this case it is 6 operations to add for each slave so in total 66 operations to add. Not fun but can be done. The other option i see is change 1 slave, delete the rest and then duplicate the first slave and change all the addresses, both the IP and the array numbers. Also not a fun job. Am i missing an option? or is there perhaps a way to make a setup that is easier changed? The thing is that this probably the first of a number of expansions that i have to make so i would rahter spend more time now then repeating the same mistakes.
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This has come up in the forum before - adding some of the Vision functionality to the UniStream. I'm working on a project that will be using UniStream PLCs as data concentrators / SQL gateways for many existing Vision series controllers via Modbus TCP. I will be talking to existing and yet-to-be-installed Vision controllers - probably 30 nodes on each network. The IP addresses I'm using on my test network are not the same as what will be installed, so when I take this over there I'll have to open UniLogic to manually re-enter the Modbus Slave addresses as part of the program. I (or the end user) can use Uni-Apps to change the Panel and CPU IP addresses in the field. UniStream has an IP data type. Is it possible to put an IP tag in the Modbus TCP Slave configuration table? Joe T. -
Hello, I was interested in the "modbus set slave ID" block with its name, but I do not know how to work with it and what it does, I also wanted to understand - is it possible to change the slave ID in Unilogic?
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Hello, I have a current project to modify a Modbus RS485 to Modbus TCP / IP gateway. I am using a US5-B10-B1 HMI with a UAC-CX-01RS4_0 card. I have to read informations on slaves (10 slaves) in Modbus RS 485 and then send these informations on Modbus TCP / IP to a Supervisor. So Master on the RS 485 com and Slave on the Panel Ethernet. I would like to be able to send the information back to the supervisor (TCP / IP) using a single IP address (of course) but having 5 slave IDs on the network and connecting to the Ethernet Panel. Is this possible with this US5? When I create my configuration as a slave, I have no problem indicating the slave IDs. But in compilation I have errors because it only accepts one slave ID on Panel Ethernet and another in RS485. Thank you for your feedback. Have a good day.
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Hello!, my name is Mario and I ask if someone can please help me with my problem. I try to control a Sinamics G120 with a V350 via modbus RTU, but I can´t do it! The connection of between the PLC and the V350 is: V350 (jumper set "RS485" - Jumper TERM: off) Port 1 - Pins: 1 and 6 Sinamics G120 X128: terminals 2 and 3 Configuration of the project: Sinamics G120 (Starter): V350 (Visilogic) I tried to change some parameters of the communication, but the problem never disappear (status message=5). If somebody can give me some help I will be very grateful! Best Regards Mario
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On upgrading my Unilogic program with compiler version 1.29.111, it now reports this error: 'The TCP Remote slave limit of 64 operations has be (sic) reached. (136)' The program previously compiled successfully with compiler version 1.29.26 and .34. I have 11 ModBus Remote Slaves on separate IP addresses, with 10 of which I request a single 64-register transfer, and the eleventh two 32-bit register transfers. If I remove all the Slaves and associated code, then the program compiles. If I then reinstate them it now compiles successfully! I have several versions of my program in development, chasing different operational problems. Do I have to repeat this procedure for each of them in order to use this latest compiler? Regards Robin Proctor
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Hi there, I have to update program on a site where we already have 2x samba 43 in place, I will need to poll some modbus values and show them on the displays from 4 RS485 devices, - VSD and soft starters, these will all be on a RS485 to TCP gateway, in my complete program I have made a separate working example of what i'm trying to do, by using 2 spare sambas i have, as a master & slave combo i just wanted to know if its the best practice way of doing it when polling the 24 to 30 different values needed I am also curious about the settings to do with SB168 Link lost auto recover, do i then need to set some time values in SI 103-110 to make it work properly? Any help or advice is always appreciated! network.vlp network slave.vlp -
For the communication with Siemens PLC’s we use an Anybus device. In the version 1.26 everything works fine. With the 1.29 version, the NumOfClients is increasing to 165 and after approx. half an hour no more data is exchanged with the Anybus device. Any ideas for a work around? Is this a Modbus bug in the 1.29 version?
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My requirement is to connect & operate 6 HMI individually (Without mirroring) with PLC and the 6 HMI screens should view from computer remotely. I Hope to do it with Mqtt protocol or via Modbus. Please can someone help me to try this cos I have done only one project using Unistream PLC with Mqtt protocol previously. Please see the attached draft design of the project.
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When I checked my project I notice error on my RS485 CPU COM port it says "Both Slaves have been set to the same communication protocol. Slave1 may be set to TCP/IP, while Slave2 is set to RS485." Does it mean UniLogic RS485 can access only one slave device ?? So if I have more than one modbus slave I have to connect second slave through TCP/IP connection ?? What happens when I have 21 devices ?? I am really screwed if there are this kind of limitation.
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Hello to all, I am working on a new system where a Unistream B5 TR22 is a Modbus TCP master to 11 Samba PLC's Nothing to exciting but my biggest problem is a lack of knowledge. This is only my second project with a unistream PLC, with the first being a very straight forward ladder program without anything special. i do have a few years of experience with visilogic so that side is not a problem. What i already figured out is how to make the set-up on the master and slave side. the thing i don't get is addressing between the devices. In visilogic i could literally select which mb,mi,ml i wanted to read or write. Now i don't see that option. how does addressing work between these devices? At the moment i am still waiting on the unistream plc to arrive, so that i can try some stuff out, butt before it arrives i would like to make a little headway before that. kind regard's Leon Mötter
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hi all I try to connect more then one master to my slave(PLC v130) with MODBUS TCP , the masters need to work simultaneously. can someone send my example how to do it? -
Hello, I have a school project where i was tasked to read an MI from a Slave PLC as a Master PLC. I've tried using the help fuction, but i havent seemed to make it work. Thanks in advance -
Hi, I'm new to the RS485 communication protocol. I am trying to communicate with a Siemens SINAMICS V20 VFD with the Unitronics Unistream PLC ( USP-070-B10) The VFD leads to a 3 phase motor I set up the baud rate to 9600, data bit to 8, parity list to none, and stop bit to 1 In addition I set up a remote slave in COM1 of Masters drop down, in MODBUS In the slave configuration I made a coil named "motor" that writes to address 40 every 100 ms I spoke with a Siemens Technician about the driver settings, and could not find a setting to "ECHO" bits to the driver I was told I need to set a transmit telegram The is there an FC03 for "read holding register" or a way to "Echo" data to 40,100 (MODBUS)? Any sort of references or suggestions for setting up communication? Thank you, Wynn Ni
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Hello, I am struggling to understand Visilogic's MODBUS tools. Say I would like to turn a light on and off from the master PLC, while the output is attached to the slave PLC. What would be the best function block to do this? I keep using the FB #5 and I will get the bits set high, but then they will stay high. I am practicing so I can use PTO utilities to control steppers instead of lights. First, I need assistance in understanding why things like MODBUS FB (5) sets and doesn't reset. The attachments are just HMI lights telling you if you get the commands from the Master PLC. (You get them only if the 2 bits begin in RESET using the online mode) Otherwise, O5 in the picture is the LED I am trying to turn off and on from the master. Thank you! MASTER MODBUS TEST.vlp SLAVE MODBUS TEST.vlp
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Hey guys, I wish you could help me with this one... I'm currently doing a project using a pump that communicates by Modbus RTU to my US7-B5-TR22. The serial communication and code is done by USB. I'm aware that you recommend to use a Prolific USB to serial converter, I have a FTDI one that worked perfectly in an other configuration but still modbus using serial by USB. Now I can't understand why on my new configuration it fails. I "sniffed" the communication between the PLC and my pump using my computer and a serial terminal, the request of the PLC and response of the pump are correctly sent. The problem is that the PLC doesn't seem to receive or decode well the response because every sessions in my remote slave are failed. Thanks in advance for your help, I attach a piece of code for you to have a look of what I've done. Cheers, Louis test.ulpr
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Hi all, I use US5-B10-TR22 to read data from Modbus slaves. Technical documentation of slaves gives such information (see attached picture). Could someone tell if in US5 is the same byte order (didn't find that information). As for now everything looks OK, but I'm afraid that there could be a problem when there will be large numbers accumulated. Thank you in advance.
