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Found 67 results

  1. Hi, I have Unistream 10 as a master and multiple slaves (8) over Modbus RS485. What device do I need to connect all the slaves into one master?
  2. Hello, For a project im working on I need to motitor serval energy sources and control multiple relays. I would like to use the Samba 4.3" PLC for giving a nice interface to the system. The problem is that I have over 30 outpust I need to control. I've found a modbus RTU (RS485) energy meter who measures the voltage and current. Also found a modbus RTU (RS485) digital output module with 16 outputs. Is it possible to use the Samba 4.3" PLC with V100-17-RS4 module to communicate over modbus with the IO modules and energy meters? Best Regards, Jelmer
  3. Hi. I have a Unitronics JZ20-R16 (Jazz2) controller I’ve programmed to run a simple air ventilation system in my house (The thing is running great btw.). I also have a self made Arduino based data logger (I use it to monitor and log my energy consumption, temperature, etc.) I’m not building those things or mass producing, Arduino electronics is my hobby - I just use it to stay sharp. So I decided to cross-integrate my air vent. Controller with my data logging unit (I want to see the status of my air vent. Controller unit on Arduino). So for starters the task is to simply send a 16bit int to Arduino and receive another 16bit int from the Arduino. The communication protocol of the choice was MODBUS through RS232 interface (as I already have MJ20-PRG; MJ20-CB200 and a MJ10-22-CS10). I’ve decided to use JZ20-R16 as a Master (Arduino as a Slave) in a 9600 baud 8N1 configuration (default for JZ20-R16). For Arduino’s RS232 interface I’ve used TTL-RS232 converter (MAX3232 based) : Experiment 1: In order to see if the Arduino’s MODBUS feature is working I’ve connected Arduino to my PC using the given connector and a RS232-USB converter. Arduino was configured as a slave and ModbusPoll software (http://www.modbustools.com/modbus_poll.html) simulated a master. I was able to both read a holding register from Arduino (03) and also write a register (06). Those are the desired options. Experiment 2: In order to see how MODBUS is working on JZ20-R16 I’ve hooked it up to my PC using my MJ20-PRG; MJ20-CB200 and a MJ10-22-CS10 later connected to RS232-USB converter. I’ve uploaded a program (by pressing buttons 1 and 4 I send an int or correspondingly request an int from slave): (see in uploaded files) It make the JZ20-R16 work as a Modbus master on a RS232 interface. In order to simulate a slave I’ve used ModbusSlave software (http://www.modbustools.com/modbus_slave.html) . Once again, the combination worked perfectly. Once again all the required commands worked. Here’s the photo of my hookup: Then I’ve noticed a possible cause for future problems : lines 4 and 7 of my MJ10-22-CS10 are actually used in this communication. It turned out that the RS232 communication with JZ20-R16 require 6 wire communication instead of 3 wire communication I’ve expected from RS232 interface. Due to the requirement of RTS and DTR signals! I’ve turned on my scope and actually saw those signals on pins 4 and 7 of MJ10-22-CS10 connector going high after the “handshaking” with my slave simulator was done. With PC USB disconnected: PC USB Connected: MudbusSlave after “handshaking”: Successful communication: CH3/4 are the DTR and DTS signals correspondingly. At this point I’ve realizes that sue to those signals I would not be able to connect my Unitronics to my Arduino, as the TTL-RS232 connector simply do not support DTR and DTS signals. So after hooking up my Arduino to Unitronics I see the following on the scope: Both DTR and DTS signals are on 0 instead of HIGH, which prevents the JZ20-R16 from accessing the modbus. The questions: Is there any chance to make JZ20-R16 communicate over RS232 without use of DTR/DTS signals? Is there an option to tweak those signals (connecting them to +5V permanently) Use of other TTL-RS232 converter? Any other way to make Arduino and JZ20-R16 communicate over RS232 interface using MODBUS Thank you for the patience. samplemodbusmaster232.U90
  4. Hi, I'm running an Arduino-based home automation system. My custom-made Arduino clones are communicating over a RS485 network (configured as 8N1) using Modbus RTU protocol. Thing is that I want to have a reliable, industrial-grade PLC in the network, in order to monitor my Arduino-based sub modules. Basically I need a cost efficient Unitronics PLC capable of connecting to RS485 network, The ladder program is expected to be non memory hungry, also I'm fine with good old 2 line display. The PLC must be able to connect to the RS485 network without the use of any extension modules/communication modules /.etc (native COM port on a screw terminal). Any suggestions? Thank You.
  5. Hi. Hope someone can assist. Installed 8 v570 units at client. First tried ethernet, then canbus and then modbus. No luck. Sometimes plc loose comms with other plc's and sometimes some plc's loose comms with omron cx supervisor scada. Any assistance will be appreciated. Thanks. Rodger
  6. Hi All! I am new to actual PLC programming and ladder logic but I have been working with Yaskawa drives for 11 years and am quite proficient on that end. I have a V1210 and have found it fairly easy to work with aside from visilogic crashing quite often on windows 10. I really want to start interfacing VFD's via modbus rs485 and I am looking for a place to start. Are their any example programs or tutorials specific to the V1000 that could help me get a start? I did see another topic similar to this, but the links the support staff listed were broken. Thanks in advance! Kyle
  7. Unistream Modbus limitation

    Hello Guys, I have trying a communication with a Unistream as a Slave and I'm having some problems. When I create a program on Unistream with 255 tags, the communication works ok and all address is read but when I add 1 more tag the program don’t work well. The master only can read about 175 address. In this case it does not matter the specific address, but the number of tags in the program. Does Unistream has a limitation on number of adress that can be read? Has anyone already had the same problem?
  8. I would like to communicate with an instrument that is using Profibus port to read analog and digital values. Is it possible to use an an external protocol converter with the Unistream (RS485 or CAN) port to connect to Profibus Slave device ?
  9. We have an issue regarding the Modbus TCP/IP communication with a third party HMI(Weintek), the read only bits can be read but I can't seem to write data on the PLC, how can I match the address that unilogic uses to the Modbus Standard( 0x 1, 0x 2, 1X 1 and so on) does this address matches exactly to that standard, say, If we configure a Coil to address 1 read only does this translate to 0X 1?, and if a second coil is configured as address 2 read/write does this means 1X 1? or 1x 2?. As I stated before, Our master HMI can read the coils configured as read only, we can even read and write registers, but we haven't been able to write to the PLC.
  10. Hello, These days I'm having a problem using modbus to reading pressure data from TROX terminal unit. It is kinda simple idea - 7 slaves (TROX units) and V700 is master and gets all the data. But as I'm conneting modbus though all of them I get error that there is no connection between TROX units. Slaves ID are set properly, cable polarity have been checked too. Maybe there are some other problems that I don't know? Thank you kindly for answers.
  11. Modbus in Vision V700

    Hi, I'm having hard time displaying data on V700 PLC. After MODBUS config and reading holding registers HMI still shows 0. Do I need to write data to data table and only then display on HMI? Data has to be read from MIO 12-V I/O module. Network ID matches, start of vector links to hmi variable. What could be done or I did wrong? Thanks. I'm attaching vlp file here
  12. MODBUS data on HMI

    Hi, I'm having hard time displaying data that I get through MODBUS. Need to read from multiple slaves, but after download display still shows 0. Maybe do I need to write data to data table and then display on HMI? Or I can just display data vector? I'm really confused, thanks in advance for your help. P.S. Program attached below. Thermofisher.vlp
  13. Hey guys, I'm often needing to use advanced modbus features because ill need to have dynamically adddressed slave ID's, or changing registers etc, etc and i cant use the built in configuration to do so. Also - the Advanced modbus still require a good bit of logic to be built in order to achieve a good Tx and Rx. I built this UDFB to be used as a single operation which accepts 4 Function In parameters, and one Function out. Example Ladder Note how the function is called, Param 'D' must be reset immediately after the function call: Ladder Image Input A is a struct with 4 members (Note that only one Arr at a time will be filled with the result data, based on your input to parameter 'B') resultBits[0-50] resultInts[0-50] resultUInts[0-50] resultRaw[0-99] The results of your query are stored here, depending on what value you use for input 'B' 1 = result store in resultsBits 2= result stored in resultInts 3= result stored in resultUints 4= result stored in raw buffer( for parsing floating point values etc, etc) Input 'C' is your input parameters for the MB request - Don't worry about the Modbus request, and request descriptor - these are handled inside the function Input 'C' is a struct with the following members slaveId functionCode = Standard codes...holding register = 3, etc startReg = starting register in slave length = how many registers(Keep in mind length of buffers etc, you can always change this) Retries = how many times to retry read request Timeout = how long to wait for response(5000 = 5 seconds -- 3 retries at 5sec each would be 15 secs for a failed attempt) Input 'D' is the Enable bit for the function to run - make sure to reset this immediately after the function call.(See image above) Output 'A' is a number with the following values 1 = read successful 5 = timeout (timeout * retries) 255 = ladder Error Let me know if i made a glaring mistake, or if you have any improvements! I'm sure i didnt do this as effeciently as possible - but, it does work for my purposes. I may add some more error checking and things later. Let me know what you think! Thanks, Matt MBR.ulle
  14. Reuse Socket

    Hi everyone! I´m using the four sockets in a Vision 130, and I need more! So, I tried to redifine a socket in run time according to some conditions, but I find out that once the socket was defined, I can´t redefine it. The socket is first initialized as TCP / Port 502 / Server. A Modbus IP configuration is attached to this socket, and running as Modbus IP Slave. Then, I close the socket... ...and redefine it as UDP The result is that the socket never loose the Modbus definition, and can´t connect via UDP. When the second socket definition is executed, the socket state goes from 20 to 34. If I insert a reset of the PLC before the second definition, all runs correctly. So, I think that the only way to "release" the socket definition is restarting the PLC. Is this right? Or (more likely) I am doing something wrong? Thank you very much!!
  15. Hi; Trying to connect to a Gardner Denver Airsmart Controller Comm Module. Serial Interface - RS232 works. Trying the MODBUS TCP UDP protocol on their ports 2000 and 2001 - no luck yet, we can ping the IP OK, just no connection for MODBUS Read Registers(3) Any one had experience with this unit? Dan
  16. Modbus Write to ABB ACS550

    Hi Guys, Just doing a addition on a project I have 12 x VSD danfoss drives working great over the last 12 months on Modbus TCP,/IP. Using control word and speed reference for control, the client has just installed a ABB drive a ACS550, taking the modbus drive count to 13, I can easily poll the drive and read the drive feed back like 102 (40102) etc, However I am having difficulty writing the control word as a Hex code of 04FF to (1) or 40001 to start the drive or the speed reference between 0-20,000 to (2) 40002 Does anyone have any ideas I have tried both 0 &1 as zero offsets but still can't seem to get the drive to receive the control or speed. All drive paramteters for ABB profile is set to Comm as per the documentation for fieldbus control setup over modbus Has anyone come across this issue with unistream writing to these drives and are there any tips or tricks I might have missed ? Thanks in advance Douglas
  17. Can someone explain the format that the IP address is displayed in the Modbus IP communications status bit and how I can display it as a usual IP address like: Cheers
  18. Hello, I just got informed about an issue with the program I have made for a Samba SM35 regarding Modbus settings. I use a Com Init block directly after a power-up bit that initializes factory com settings. If I enter Information Mode and change the serial settings for RS485 there, everything is fine until a power loss. The settings are overwritten at power-up. Is there a way to prevent the settings from getting restored to Com init settings after a power-loss or unit shut down?
  19. Modbus word to bit array

    We have a Unistream HMi which is connected to a remote Modbus Slave (Prosoft PLX31 Modbus Gateway) I need to read the bits from particular words which hold the status of sensors mapped to the Gateway tables. On the holding register entry page, it does not allow for just reading 1 bit of a word. Is there a work-around or some example of plc logic that will take that register and read the bits into a bit-array? Thank you,
  20. Hello, I'm using JAZZ JZ20-R31 as a master to comunicate via modbus. Is there possibility to use another master device on the same line which would read data from JAZZ? Requests from one master would be about a minute interval and around 15minutes from the other, so there would be little chance for interference. I know this isn't the right way to do this, but just curious... Is it possible to do this or is JAZZ somehow "locked" and unable to be read by someone while JAZZ itself is operating as a master? Thank you, Regards, Pawks
  21. Does anybody know if Vision controllers (ie V130) support Modbus TCP or do they support the Modbus RTU over TCP implementation. The difference is that the first follows the original Modbus TCP frames (ie no CRC) while the latter encapsulates the serial RTU framing sent over TCP media. Which one is supported by Vision and the other Unitronics controllers?
  22. Good evening ladies and gentlemen, I have 4- V430-J-TA24's, serial (RS232, 9600, 1, none) MODBUS, one as a master (MTU), and the other 3 as slaves (RTU). port 1 on each unit connects to it's respective radio modem. The MTU polls the 3 RTU's successfully and the cycle repeats. Here is my problem: how do I detect a comm failure on the slaves that will set a MB to clear my outputs and registers? The master reads a register from RTU1, here it can use the status message from the RHR #3 and use a compare if MI96 (rhr#3 status) = D#5 then ----[R] (MI100, the value displayed on MTU, fetched from RTU). Now on to RTU 3 and 4, they only have a MODBUS config FB follow by a SCAN_EX. How does the RTU know if updates cease? The registers and coils will just hold their last set values. My thought is having the master toggle a MB on/off in the slave, then somehow implementing logic in the slave to detect if MB being stuck in a 0 or 1 state for greater than a defined amount of time. this would trigger a bit that would zero out the coils in the slave. Please someone tell me there is an easier way. Also what is the reason that RS232 port 1 (RJ11) seems to be disabled while connected to a PC with the USB cable? Thanks!
  23. Hi everyone. I tried to use a MODBUS configuration using an indirect declaration of SLAVE ID, but didn't work. (see example in index 2 and 3 below) If I declare the SLAVE ID in a direct way, all OK. My problem is that I have to read several slaves from the PLC, and is realy hard to do with a fixed Modbus configuration. I am using a V130 in revision 9.6.0. Thanks in advance. Regards, Javier. P.D.: Sorry if I posted this twice. I couldn't find the first post.
  24. update: 12-10-16 I take that back, I failed after two weeks of trying every conceivable configuration to implement a complete working model of serial MODBUS with read holding register and write coils exchanges to four vision slaves over RS232 radio modems. Has anyone out here successfully setup a Unistream master to a Vision slave, serial, 232 over modems (RF), read registers (more than one) and write coils; without errors? For example sequentially reading five 16 bit integers and in next line of periodic slave table writing a 10 bit array of coils (or a single 16 bit write register)? 9600, 1, none, must do four RHR #3 and write coils (10 but array) to four slaves all in a cyclical (periodic) fashion. I can't make it work to save my life. I really need to know if anyone else has a working UniStream to Vision serial modbus system working as expected! Now IF you only do read holding registers or only write coils THEN it works fine. However when stacking different MODBUS operations into a single slave table in periodic mode one or the other function takes precendence over it's neighbor. I had the latest version of UniLogic and UniStream firmware as of December 1st 2016. Had to table the UniStream and go to a Vision 1210 to complete my project. However I desperately want to use the UniStream as an MTU/controller in my project.
  25. I notice that the Unitronics MODBUS communications function, "Read/Write Mixed Data", crashes the communications if I try to use it between a Vision controller and a UniStream controller. This is a VERY handy function and I'm wondering if there are any plans to make the UniStream compatible with this function.