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Hello PLC expert i need your help. i want to use OPC communication and Matlab to read and write data from/to a Logix5561. A Topic is already configured on RSLinx. On my PC i installed MATLAB and i can connect to the OPC Server using Simulink opc Toolbox. My Problem occurs when i want to add Items, i receive a Simulink error saying Name space Browsing not avaible. and Matlab says could not retrieve name space for Server. Error was: StartItemId is not a branch in the Server Namespace Additionaly i have RSView32 as an OPC Client too and although it is working fine, there is an error saying: OPC Error :Server the item is no longer available. could the error in RSView32 be the root cause of my Problem ? edit: I forgot to mention, that on Simulink opc read and opc wirte box have the Mention disabled in brace .

I need to communicate with a Mitsubishi PLC using Matlab. To do that, I open a serial communication with the appropiate parameters (7,e,1,9600), and write an ASCII message based on the manual I have (attached). I have tried examples as the one in the attached image. The response starts with a 6, that is, the ASCII number for ACK, so something must be working. But the rest of the response is junk (149, 149, 149...), although its length depends on the input length (if I add terminator, the response is longer, and so on). I am completely stuck. Some information that might be helpful: I am using a Serial to USB converter that I have used successfully with other PLC (which used Modbus, so everything was easier) There's a VB application (of which I don't have the code) that is able to connect to the PLC (I need to connect directly without using this intermediate app). I have decompiled it trying to get some info, but was just able to confirm the 7,e,1,9600 parameters, since the rest of the code is too mangled to analyze The attached manual was sent to me by the guy who designed the PLC and its ladder code, so I guess it is the correct one I have tried the echo mode (TT) to no avail, response is always the same I have some doubts regarding the reading of a value (see attached image). Why is there a second message from the PC? Shouldn't I just need to read the response? GX Developer tells me that the address D8120 (which is supposed to define the comm format and protocol) contains a 0, which seems weird. Any help or hint would be greatly appreciated. Thanks jy992d69901e.pdf

Hi everyone, I am newbie in here. I am associated with a rail integrator company in Finland, which is specialized in providing EN 50126/50128/50129 SIL 4 certified control solution for railway signalling and interlocking. As of now, we have been using HIMA PLCs (HIMax, HIMatrix), a proprietary HIMA OS and HIMA's IDE (SILworX). As of now, we are pretty satisfied about HIMA's performances. But we are also assessing some alternatives, which are based on open standards. As per our findings we are looking into the following: Hardware: Artesyn's ControlSafe Computer Platform and MEN Mikro Gmbh's MH50C Platform OS: VxWorks, QNX, PikeOS, Integrity IDE: SCADE (ANSYS), Prover, Flexisafe (Infoteam), Codesys, Matlab (?) Since SILworX is based on IEC 61131-3 languages, and our applications are made up of function blocks, we are trying to avoid platforms like C, C++, AdaCore etc. It would be great to have some inputs on these, and also about some other alternatives. Thanks in advance! :)    

Hi guys, I'm in the middle of a little university project, I'm attempting to implement a control system purely based on artificial intelligence. A neural network will be used to map the characteristics of a power plant. A fuzzy logic controller will be used instead of the conventional PID and finally a genetic algorithm will be used to tune the controller while the system is online. This is all simulated of course. Each of those AI's will be developed in Matlab. Only problem with that is, is it outputs the code in C or C++ (From memory). I would have to convert this to structured text (Based on Pascal). So to circumvent this problem I thought I would just directly interface matlab to the PLC (Schneiders M340).  My idea being, all the calculations are done in matlab which are then sent back to the PLC. However this presents me with a new problem of how I would be able to interface matlab to the PLC. If anyone has experience with this sort of connectivity, any advice would be greatly appreciated. Thank you in advance, Luchek

Hi, I work as an industrial programmer primarily dealing with Allen Bradley, Mitsubishi, and Omron PLC's as well as various peripheral devices. I would like to begin the process of learning computer programming as it pertains to the manufacturing industry. I'd like to learn how to write databases (SQL, etc) and VB apps and eventually I'd like to be able to write applications that can communicate with PLC's and other devices (although the last one would be a ways down the road).  I have very little experience with computer programming so I don't really know where to start. What language should I learn first? What free software is available to learn with? What resources do you recommend I use? I've downloaded Visual Basic Express and found some introductory courses online that I've just started but if there is something else I should've started with I'm open to suggestions. Thanks