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I am trying to establish a Modbus connection from a laptop to a Mitsubishi inverter (FR A-800 E series) (the manual for this connection can be found [here][1]) I am using pymodbus and I can establish a connection, but the problem comes when I try to read a register. I know I am connection because doing something like: from pymodbus.client import ModbusTcpClient client = ModbusTcpClient('192.168.15.10', 502) client.connect() results in a True response. Also, if I just print `client` it returns the details of the connection, which makes me confident the connection is properly establish. But, whenever I try to read a register (which I am confident exists, since it appears in the manual) : result=client.read_holding_registers(9,1,1) print(result) I would obtain: Modbus Error: [Input/Output] Modbus Error: [Invalid Message] No response received, expected at least 8 bytes (0 received) and if I try again, Modbus Error: [Input/Output] No Response received from the remote unit/unable to decode response. Does anyone have any idea? I have tried with a bunch of addresses for the registers, I have tried including not including the 1,1) part when reading the register and got no luck.     [1]: https://dl.mitsubishielectric.com/dl/fa/document/manual/inv/ib0600628eng/ib0600628engd.pdf)

Dear Forum, I am working on a set of "drivers" for some VFDs and wondering about you guys experience with it. The system layout is as following: FX5UC RS-485: MODBUS-RTU RS-485, lets say with 1x Mitsubishi F840, could be other drives (one drive per FX5UC) Ethernetport: Connected to GT2510, using Freqrol driver Another setup is for some other reasons not possible. I want to have one PLC program for different connected VFDs, scheduled VFDs at the moment are: Mitsubishi F-840, ABB ACS880, Toshiba L.V. VFD, Toshiba T-300MVi.   What I want to do: Read & Write status information - done. Read monitoring values - done. I want to setup some VFD parameters via the HMI. Send the parameter to the PLC and from the PLC to the VFD. The parameters are "basic VFD parameters", every VFD should have, such as: Torque boost, accel/decel time, min/max frequency, base voltage/frequency, etc. Of course these parameters are not simple Pr.0 to Pr. 125 but spread all over the place. I want to check for min. and max. limits inside the PLC before transmitting the data to the VFD. Knowing "basic parameters" will turn out quickly to "VFD specific parameters", I want to be prepared on the programming side. The APSRW for read/write parameters are called through the program and hand shakes with other APSRW calls.   What would be a good approach do to the above?  I rather invest more time into the PLC programming rather complicated HMI-Handling. Reading simple 125 words and the next 125 words, then writing 125word and again the next 125 words? Reading / writing individual parameters? Reading / writing 125 parameters at once? Any other approach for implementation?   Best regards, MarkusR  

Has anyone done a Mitsubishi FX5U PLC Modbus interfacing with an Omron NX1P2 PLC? Trying to find that since no manuals exist on the Mitsubishi site as well as Omron. 

Hello everyone Does anybody knows how to estblish a communication between 2 Mitsubishi CPUS with modbus? THey are RCPU and FXCPU  

Hi, data registers are getting full, because of extremely high speed pulsing is there any way , if the data value in register goes above the capacity of 32 bit register, it automatically attaches itself to next set of data registers so lets say if data was written in D10,D11 Upon reaching the limit, it goes to D10, D11, D12, D13 please share if there is an alternate way to do this

Hi, data registers are getting full, because of extremely high speed pulsing is there any way , if the data value in register goes above the capacity of 32 bit register, it automatically attaches itself to next set of data registers so lets say if data was written in D10,D11 Upon reaching the limit, it goes to D10, D11, D12, D13 please share if there is an alternate way to do this

Hi, I'm Jovel, I'm new to learning how to program PLC. Just want to learn how to use Omron Sysmac Studio . I have a question about the Data Type Data Type - Structure ( Offset Type - Offset Byte )  / Union   I Don't Understand this 2 Data types and how going to use them, can anyone teach me and have a sample program? Thank you

Hi I need to get data from a modbus rtu device to Omron PLC NJ501. I am using SCU32 or SCU42 as serial gateway. I have tried using sendcmd function, but I am having problrm with the DstNetAdr Here's my setup Cpu NJ501 1400 ID262 OD263 AD041 V1 EIP21 SCU32 My sendcmd parameter DstNetAdr.NetNo:=USINT#0 DstNetAdr.NodeNo:=USINT#4 DstNetAdr.UnitNo:=BYTE#16#84 senddata array 02 03 00 6A 00 02 E4 24 Anyone has any idea on how to do it?

Hello, i have a curios problem in a modbus tcp reading from a client.  The HC900's answer for the variable 20 (holding register 6375) is clear in the Hybrid Control Designer (the variabile is a simple counter of flow gas counter). The ammount of value is incremented every pulse from a digital input.  But when i send the request from a client modbus, the value's variable is different (completely). For example the value is frozen from this morning, probably when the machine started up.     The others value read directly from  analog inputs are correct. Only this value elaborate from some blocks show this problem. I can't understand the cpu's logic for elaboration the exchange area memory modbus.   Best regards, Ennio .

Hey guys,  I'm trying to build a therapy tank for burn victims that requires a few automated processes of which I need help! Essentially this device will function a lot like a temperature controlled "hottub" with an circulation pump but on a much smaller scale (like 10 gallons). I would also like to be able to observe and control the device remotely outside of the users direct control for programming therapy temperatures. The goal with most patients is to start them at a temperature just under body temp (around 94) degrees and the get them down to treatments in mid 60's over time. The machine will used a liquefied burn gel that has a consistency like thin vegetable oil.  Here's what I need in a controller: ON_OFF functionality for a liquid chiller.  Contact relay for reed switch to disconnect power to device when lid is open. (this is a safety feature - when the treatment tank lid is opened I would like for a relay to disconnect the chiller's power through LV to ensure there is no chance of electrical shock.  "Delay On" relay (The chiller is and on_off refrigerant based device that will require a "delay on" relay to allow head pressure to dissipate before restarting) (See below) ON_OFF relay with programmable timer functionality for a liquid circulation pump. (to be set at intervals throughout the day) Temperature controller for K-type thermocouple - this will be used to monitor, maintain, and cool liquid. PID or Arduino? (Will need the ability to establish limits on backend) The ability to display temperature in either F or C Functionality: Ideally each unit would have a controller similar to an on_off temp controller or PID so that the home user could manipulate controls within a limit on the device locally. The device would then automatically maintain temperature based on set point and would have timed on_off sequences throughout the day for the liquid pump which were programmed into the device logic. This functionality in addition to the safety cut off features for use are all I need this device to do. Safety feature - being that this device could be in the middle of a chilling cycle when a patient would want to use it, I would like for the device to have the ability to instantaneously cut power to the HV 110V 16A Pump and Chiller without damaging those devices upon restarting... For instance if someone were to open the lid to feel the water and close the lid again quickly, the on_delay timer set to around 5min would prevent the compressor from restarting until the 5 minutes passed, thus keeping the short cycling from damaging the refrigerant system.   Remote monitoring and commands I would like to have the ability to push settings to these devices all across the city/state in peoples homes. The controller would need the ability to connect to wifi and transmit information as well as receive commands. This feature would be for those who would be put on a therapy program where we would control and push temp settings to their device remotely. Mobiel User Interface The BIG goal would be to tie all of this together and be able to control a device via iPhone or android. User downloads the app - The app has the ability to: turn on off off the device  adjust temperature (again within limits) turn on a timer 15 minute filter cycle with the press of a button Select/program a filter schedule with up to 8 time slots Circulation filter replacement reminders (messaging function) Therapy reminder.  Opt in for therapy pre programming pushes - me pushing temp settings to their device. Thats the novel for now!! Looking for someone interested in building this, or anyone willing to guide me through the process. This is just an idea and my 9-5 is a physical therapist, but I would love to bring this vision to life!   Sorry if this is fragmented or ignorant, but I just need help getting started or pointed in the right direction! 

Hi, This is Kaviraj. I am using Q06udv cpu + 3 ethernet cards ( 1 eth card for kepware connect , other two cards for modbus tcp connecting 16 GOC43 devices through predefine protocol). I am getting the data to PLC but facing below issue.  Problem-01 (major) in 2nd and 3rd card i am facing X19 (Initial normal completion signal) bit OFF after some time randomly like 1 or 2 hours later. Problem-02 Connection ports are closing regularly like  1.5 sec to 2sec after port open status. so i am managing by executing port open instruction instantly after 200ms of port close status. Need help, pls support.     

I am currently trying to connect my OMRON NX1P2 1040DT1 (Using CIF-105) to my Unitronics V570 PLC, With my OMRON PLC as Master. It seems as if Unitonics Rs485 only wants a six-wire connection type but my OMRON PLC wants a 2-wire or 4-wire connection, Wondering if anyone has a solution to my problem and can assist me.  

Hi, I have a problem with serial communication (no protocol) using rs485 module, the received data is error. I'm using CP1L CPU, CP1W-CIF11 module as transmitter, and USB to RS485 converter as receiver. When I check the received data on PC, it's incorrect (bit error?). I just send 2 bytes data, 0x61 ('a') and 0x62 ('b'). My configuration: DIP switch CPU 4 = off, DIP switch CIF11 1 to 6 = on,on,on,off,off,off, 2 wire RS485. (I also attached the program and settings) https://postimg.cc/gallery/pr293Jc   Could you help me to solve this problem? Thanks   Program and Settings:     Result:   

HI, I'm reading values from an SBC SAIA PLC ( PCD2.M5540 model). My problem is that some values are 32 bit, while modbus return 16 bit values, of course. Registers are consecutive, so I cannot read for example 9008 and 9009 since they store 2 different information.To make it clearer I attach the PLC watch window. As you can see R9009 is a 32 bit value, but I can't require R9009 and R9010 via modbus since in R9010 register there is a different information. AS well as in R9008. Speaking with SAIA technical support, they explain me that their PLC registers are natively 32 bit, so in order to read them I need a 32bit modbus client. I cannot find anything like this, neither I can use standard modbus, since the buffer I get back is a 16 bit for each register. So 16bit for R9008, 16bit for R9009, 16 bit for R9010. What I can do?Thanks

Hello, everyone! I am following this YouTube tutorial where it teaches you how to add a block of Modbus server within Studio 5000 for communication with plc ControlLogix. The video: https://youtu.be/qcF4m7rPjkw However, according to a comment from the author of the video himself in my comment I can make such a connection through a Modbus device. How do I do this within ur5 and how can i access UR5 inside Studio 5000?

Hi, I'm new to the Mitsubishi world, so may be anyone help me in a quick! I need to test a my client with the Mitsubishi MODBUS tcp.  To do this I would like to avoid use a real plc and use  the Gx Simulator3 that come with the Gx Works3. The question is: the Gx Simulator3 is capable to simulate a MODBUS tcp module? To be more specific I tried this: - created a project in  Gx Works3 with a FX5U CPU. - configured the FX5U built-in ethernet module with IP address of the hosting pc (also tried 127.0.0.1 with no success). - activated and configured the MODBUS muster to the built-in ethernet module. - wrote a trivial ladder program with a 1 input and 1 coil. I can download and run the project on the Gx Simulator3 but I cannot connect to tcp port 502 that I supposed opened by the MODBUS muster functionality of the build-in ethernet module. Do anyone know if the Gx Simulator is able to simulate modbus tcp functionality?   Thanks in Advance Luciano.       

Hi guys I need to test some code in an FX5U PLC,  but I don't have the PLC here so I'm trying to simulate it in melsoft gx works 3, but how I can test the Modbus tcp/ip if I do not have an IP address for the plc  someone has ever communicate both software, gx works 3 an som modbus master software ??

Hi All I am trying to connect Cognex OPC Server with Mircrosoft SQL Server (SMSS). Do you have any idea how to do that? I couldn't find relevant information online.

Hello everybody. I need a solution for Modbus-TCP server on the PLC. With the FX3U it would work with the FX3U-ENET module. The internal interface of the FX5U should actually be able to work with the library of the FX3U (FX3GModbusTCPServer_GW2_V100) or not? Because a socket connection is now possible. I would be happy about suggestions. Dave

Hi Everyone, I have a small project where I need to detect temperature and smoke using Allen Bradley Micro820 PLC and send email when the temp is above or below a set limit. And since I'm new to PLC world I'm not quite sure which sensors would work with my plc model. It would be really helpful if anyone could guide me through and suggest any sensors appropriate for temperature (surrounding temp not liquid temp) and smoke. 

Hello, I'm new to setting up my controllers and communication between devices.  We wanted to see if using Modbus TCP/IP to communicate to a load bank was the right path for us.  I was able to configure my Micrologix 1400 controller Channel 1 for Modbus and set the data files.  I set up a read holding register 03 message, two write single register 06 messages and one write multiple registers 16.  I was able to read the data from the load bank, but I was unable to send any write commands.  I didn't get any errors in the messages.  I was able to send write commands through my pc to the load bank and it responded properly.  So I was thinking I must of missed something in my set up in the PLC. I'm attaching the PLC Program and the command set from the manufacturer.  Any help would be greatly appreciated. BENCH_TEST.RSS ALx Series Input Command.pdf ALx Series PWR Command Page.pdf ALx Series Setpoint Command.pdf

Hello,  after I updated my CMT-FHDX with codesys license, programming and uploading codesys i'ts ok , but I can't upload my CMT-FHDX project anymore. I see CMT  in easyweb, but easybuilder won't find the IP (won't recognize CMT HMI even if I manually add the CMT IP address)...so I can't upload project When trying to upload in easyweb, it's fails. I't say that is not the correct project (CMT-FHDX-220). I reset to factory de CMT and still the same problem. Before I updated with CODESYS license, I was able to upload succesfully projects to CMT-FHDX. Now I can't Please any advice Thankyyou

Hi all; I have Delta DOP110 IS hmi and i have a modbus tcp device. I want to communicate hmi and device with modbus tcp/ip but i didnt understand device's register address. For example, input bytes 0,1 analogue control word, What is the register address? 40.000 or 40.001 can you help me ?  

Hello, I am rather unexperienced with PLC's but have some experience. I Currently have 2 Lexium ILS1 motors which we want connected over RS485.  I have read a couple of manuals. I have found which format they want to receive their data and what the pinout of their pre assmbled cable is (which hasn't been delivered yet).  I am currently unsure about a couple of things. The wiring the formatting of my data i'm sending, and the program.   The pictured below show my motor (which runs when i connect it to the PC and run it using the software provided so it is in working order) and the PLC with option port (which i used to transmit data to another PLC, so again i can't blame the hardware for being at fault here). However when i connect the cable and try to communicated I Don't see the LED light up. I followed Lexiums guide on which pins to use. But i figured for good form i might include these pictures to be certain hardware is correct.      Finally here is my program. I followed Omrons quick start instructions. But: my send ready flags never become high and the way data has to be formatted for these lexiums seems very labour intensive. But this is how i understood it needed to be done. Am i doing something (or a lot) wrong here?      I hope someone can help me out here! If any further information is needed i'll do my best to provide it.   Kind regards.

Hello everyone,  I have a problem, i want to read inverter holding register using modbus tcp. I am using QJ71MT91 and ABB580 FENA-21. QJ71MT91 successfully opened and no error was detected. I want to read the address to 101 and so on. in automatic communication parameter >> I have tried changing the target MODBUS Device Head from 0 to 102, and I got error code 7360. do I also have to use the auto refresh setting? I ask for guidance PLC Q03UDECPU : 192.168.3.181 PLC QJ71MT91 : 192.168.3.121 INVERTER : 192.168.3.11  i use gx works2   best regard chelz96