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  1. I have a US5-B10-RA28 with a UAC-CX-01RS4 card fitted onto the back. I have 2 sensors needing to be wired to fit the PLC Program, however the 2 sensors have a different default parity value, meaning they don't work together and only work when I set the 01RS4 card in unilogic program to either Parity = None for one sensor and Parity = Even for the other sensor. This however is not suitable for my application as I constantly have to redownload the project to the PLC changing the parity value for the module to get one sensor running. So my question/ help needed is how can I change the Parity value of the sensor below, and is there a way of doing this through unilogic? Thanks Soil Moisture & Temperature Sensor User Manual-S-Soil MT-02.pdf
  2. How can I use the data from 2 different plc's on the v700 by making a connection and do I need to use any additional module to display this data on the screen?
  3. 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
  4. Hello, I would like to ask you for help with connecting the GSM module Cinterion BGS2T via RS485 (modbus). Does anyone have experience example of how to connect GSM SMS sending via RS485 not RS232. Thank you Tomas
  5. Hey all, I'm new programmer in visilogic IDE and my device is v130-33-TA24. My program purpose is to communicate via RS485, 9 bits to receive data from device. I initialized COM1 and set protocol Send&Scan by the connected device protocol. but nothing is show on screen(I've linked the received data into number on screen). I add some pictures for description. I'll be glad for help
  6. Hello togehter, I use a V1210 for my Visualisation Project of digital pressure transmitters. They are working with RS485 BUS and their own Protocol (Meriam Serial Protocol). In first test i tried to get the information how to Request via RS485 a new Measurement signal and in which format the transmitter is answering in a Response Frame. In this Case i already know that i have to send on RS485 Bus /11920Baud 8 Data Bits 1 Stop Bit Parity: None the following Frame(hex): 80 01 00 05 0B 04 92 00 00 00 06 10 05 80 80 0B F0 40 Answer: 40 01 20 0B 05 04 92 00 00 00 7D 9D 00 02 03 00 F9 4E 4A 41 C1 5E 58 BD 1B 3B 5E 41 00 01 01 00 E9 60 B6 41 91 DE B5 41 52 07 BB 41 0B F0 40 05 80 80 In the marked 4 Byte-little Endian Code is the Pressure of my transmitter shown. HEX: F9 4E 4A 41 Float - Little Endian (DCBA) : 12.64428 How can I implement such a Request Frame and how can I manage the Answer frame for visualisation of the pressure value? I already setted up a Protocol Config and a PROTOCOL Send - in the Protocol Send Block. But after closing and reopening the Code is missing?! Looking forward hearing from you soon. Kind Regards Alexander   
  7. Hi, For personal use I'm using a V280-18-B20B with a V200-18-E1B. snap-in module. In order to register temperatures, I'm going to use a (third party) Pt100 I/O-module which communicates via MODBUS RTU. According to the documentation I would have to configure comm. port 2 of the V280, through jumper settings, for RS485 communication. And, again according the documentation, these jumpers must be present on the circuit board directly behind comm. port 1 and port 2. But unfortunately in my case there are no jumpers on my V280 to set comm. port 2 to RS485. Several questions popping up in my mind: Are there V280 models which don't have these jumpers to set comm. port 2 to RS485? Is the documentation incorrect and do I have to look better (and on a different place) on the circuit board? To communicate through RS485 with the V280, do I have to purchase the V200-19-RS4 Snap-in module (RS485 comm. board), because comm. port 2 is just not configurable for RS485 on the V280 (which I actually expect, because the name at port 2 only indicates RS232. If port2 is also configurable for RS485, you would expect port2 to be labeled RS232/RS485). In advance, thank you for your response. L.
  8. Hi everyone, i'm new here, i'm working with plc, but i have unitronics usp-104-b10 on my desk up to now. unilogic version: 1.28.34 I need to solve crc checkum rs485 specific protocol of one noname thermostat. I tried it through message composer but it failed. Thermostat works, I tested it with com debug, connection is ok. Checksum definition: checksum = (header + command + id1 + id1 + data0 + data1 + data2 + data3) and FF xor 3C example: # H30 = (# H0B + # H00 + # H01 + # H00 + # H00 + # H00 + # H00 + # H00) & #HFF xor # H3C it should look like this: txBuffer = 0B 00 01 00 00 00 00 00 30 do you have any idea how to solve it?
  9. Hello friends. I am using a USC B5 TA30. This PLC is communicating with 4 frequency inverters in RS485. I managed to establish communication but it is very unstable, the problems are as follows: -It does not update in real time, it takes a few seconds because I need to be updating the routine call manually; -All the inverters are configured correctly and work individually just by changing the cable between them, but when I connect them all there is no command of two or more (each with their own address); Some data that may be relevant: -All equipment is functional; -They are Toshiba inverters of the VSF15 and VF-FS1 lines; -The distance between the components is small and I'm working with 9600 Baud Rate, Parity None, Stop Bits 8; I think the problem is in some configuration in the call of routines related to time or ModBus configuration of the UAC-CB-01RS4 cards, the RX / TX LEDs are blinking and very fast as usual in OK communication. I already have an HMI in the same communication working on the other UAC-CB-01RS4 card, it also has a little bit of instability, but it reads and writes the data on the PLC. can anybody help me? Thank you very much and I wish you well!
  10. 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
  11. Dear all, We communicate 10 nodes through rs485 communication in v700 port 1..the problem is if my one divice is failture means other 9 nodes getting delayed..kindly provide solution RegArds Mohamed
  12. Hello my friends, I have some difficulties communicating with a power meter, it has a Floating Point 32 address, and I can't communicate. I performed tests on KepServer and got success and also with ModbusScan. You could be helping me set up the program or teach me some procedure you might be doing to establish communication. Attached is the list of registers.
  13. Hi there, this is my first time working with unitronix plc and I have some problems with understeanding how does modbus communication works. I am using visilogic 1210 plc and I want to read some parameters from Iskra FPC400. I want to use modbus because FPC400 only supports rs485 communication. First I did set up com port and configured modbus. (As you can see from pictures that I included) I want to read 27 parameters from FPC400 (As you can see from picture that I included, I want to read 27 parameters from adress 4112 - 4139 ) and store them in 27 different variables in my plc. (MI4000 - MI4027) As I understood, I need to set start of vector for reading variables as 4112 and length needs to be 27, and start of vector on my plc is 4000. Does this means that program will read 27 parameters and store them into my plc starting from MI 4000 to MI4027?
  14. Hi, I'm trying to build a snooper that works on a modbus RTU network, to test a controller built by a third party. In this situation the Unistream is neither a master or slave, so the built-in modbus RTU configuration isn't suitable. I'm struggling to to get messages recieved consistently using the COM Rx ladder block. (it doesn't help that this ladder function isn't documented in the help file, specifically how it determines message boundaries in the absense of STX/ETX characters). I'd like to know that each time the "Data Arrived Bit" goes high, the first "RxLength" bytes in the "Rx Buffer" are new bytes, but that doesn't appear to be the case. With the attached code, I get an entry in the 'Raw' Data table for almost every scan. With condition before the COM Rx removed, it works better - but not a lot - there are lots of duplicate message fragments, but occasionally I get an unbroken and unduplicated sequence of characters which can be reassembled into a valid message. Any recommendations on how best to use the COM Rx function for this?
  15. I have three V430-J-RH6 PLC's, they will be communicating via RS-485. Each of these plc's are running two pumps for that specific unit. My end game is to make sure that none of the units have pumps running at the same time so we don't have power issues, ex. Unit 1 is running a pump so unit 2 and unit 3 cannot run their pumps until unit 1 is finished etc. I know how to program that part in but my struggle at the moment is with how to best get that information to each PLC. I need each PLC to have constant feedback of information from each other PLC. I need each unit to know when the other units are on and off. Is a struct command the best way to do this? If not what is, and how do I implement it? I have looked into the help files on Modbus master and slave for sharing information (read holding registers, and preset holding registers) but it doesn't look like they can share MB's between plc's? I also don't quite understand how those work. Any help in this would be greatly appreciated!! Thank you! Unit 1 Governor Pump_7.31.18.vlp Unit 2 Governor Pump_7.31.18.vlp Unit 3 Governor Pump_7.31.18.vlp
  16. I have multiple devices such as printers(2) and scanners(2) that I want to communicate to using only 1 COM port in V1040 PLC. Printers and scanners support RS232/RS485 protocols. Can someone suggest on how can I achieve this? I looked at options with Modbus protocols, but I didn't understand how can I assign network id's to my printers and scanners. If I am required to have any additional hardware, please suggest.
  17. We have an RS485 based communications issue We are using a Unitronics V430-J-RH6-N to communicate to a network of up to 4 slaves, consisting of Ziehl-Abegg Modbus modules. The ZA module wiring requires that, in addition to the data lines, the ground connections also be daisy chained together. This is what I am used to. The Unitronics communications connector does not specify a ground connection on the 6 pin RS12 connector provided. They only mention using pins 1 and 6 for Data A and B. 1. Where at the PLC do I terminate the ground for the RS485 circuit? Currently we have it tied to chassis. 2. Is there a possibility that tying the V0 ground at the PLC to Chassis, as suggested in the Unitronics documentation, could be causing us issues? The ZA socuentation specifically mentions NOT to connect the shield on the cable.
  18. 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?
  19. 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.
  20. 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
  21. 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 ?
  22. Hi ALL! I have problem with RS485 in V1040 between V280. I create test program for testing communicate between two controllers. At first i change V280 PORT2 to RS485 terminal and V1040 PORT2 to RS485 terminal. Second connect with RJ12 1---1 6---6 but Master not Read Slave. Can you help me? In attcah test program. MODBUS slave v280 RS485.vlp MODBUS via v1040 RS485 master.vlp
  23. Hi, I have a Vision V1210 Controller that is supposed to read float values from pH meter over RS485 MODBUS RTU. All the communication is fine, using "Read Float Registers" FB the float value is stored in two consecutive MI registers (MI0 and MI1). I can see that retrieved value is 32bit float ordered big-endian (I believe that's IEEE 754) and I was wondering if there is some way to display it on screen? One way would be converting it to some integer representation so I can easily put it in a numeric box and use 1.2 decimal format (pH values should be in range 5.00-9.00), but I haven't found any ladder element for such conversion. Am I missing something obvious? It's worth mentioning that I don't need to do any calculations on these floats, just display them on screen. Thanks -- Petar.
  24. Hello again, since your answers are very helpful and I could not find information I need on this forum, I`m starting new topic. I need to set up communication between V280 and multimeter DMK 22 by Lovato. Here is the tutorial they sent me: https://www.sendspace.com/file/trigbh(file is too big to be attached here on forum) I have several problems with understanding the whole communication. I have working MODBUS IP communication between PLC-to-PLC, where the communication is done through MODBUS R/W Mix, which I understand how it`s done. Here I need to get from the slave multimeter 3 values. First question: How do I send message to slave? The message should looke like this: 08 04 04 00 00 00 64 63 6A, do I have to send it as vector of HEX MIs? And the message I get back from slave will be vector too? If you don`t mind to explain this a little bit detailed including a little tutorial how to set it up correctly in VisiLogic, I`d be very happy. I have to solve this in 2 days. Thanks in advance a lot! Unitronics community is great and I will surely write it down to my thesis and recommend you. Best regards, Martin P.
  25. Hi all I am using a V430-j-t38 with add on Ethernet card. The problem I am experiencing is with the built in Com port, I have set the dip switches to rs485 and we use this port as a Modbus slave from a Motorola Ace3600, I am being sent a Vector of values in MI 141,142,143 The problem is my plc interprets the information wrong and loads all the data into MI 141 as 19456 when at the moment it should be 36, 1796 & 666 but the current values it should send don't really matter I seem to just get 19456 The data being sent doesn't seem to be a problem nor does the PLC really because through testing we have tried, A samba running same code as v430 slave but with add on rs485 port - works correctly The V430 using an rs485 instead of Ethernet add on port - works correctly The samba as master sending data to the V430 through inbuilt port also works correctly The problem only is when using the inbuilt port connecting to the Motorola PLC Can anyone make any suggestions? I know its not the Modbus config or com init blocks because it is receiving data its just messing up the values somewhere Thanks Kieran
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