ILC_H

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 .

Ok guys i start to see some light at the end of the tunel. i call the rockwell support and the said i schould first  make sure i have Gateway Version of rslinx installed, since i want to make a remote connexion.  Then i use this link https://rcschallenge.inl.gov/opcserverclient.aspx to correctly set up DCOM on remote and Client PC. On the Client PC i can read the data on MatrikonOPC Explorer but not on MATLAB. Attempting to connect to remote OPCServer with matlab using OPCServerinfo('192.168.1.99') will not work and the error says either "ACCESS DENIED". or "error in security package"  

Hello Guys, thanks you for your Replies. I tried  both Drivers Ethernet Devices Driver and Ethernet/ IP. I added :EIP too as Pcmccartney1 suggested.  I already have a PC connected to A PLC through Ethernet/IP Driver and that just work fine. What i want, is to connect my PC as a Client  to the Computer connected to the PLC.

 Exactly yes i can ping the PLC from my computer. I can also ping my Computer from the PC. but in rslinx it seems like there is no connexion between my computer and the PLC . 

ok in that sens i have a proper TCP/IP adresses set too. The IP of the PC connected to the PLC(192.168.1.100)  is 192.168.1.99 and the IP of my Computer is 192.168.1.105

Hallo ilarson007 what do you mean with properly? i have the same issue

the other PC doesn't need rslinx, since it's the Client. I  configured rslinx on the Server. Now with the help of the IT the communication between both Server and Client work. Still i can't see the OPC Server on MatrikonOPC explorer

Thanks you for your reply Boblfoot, i forgot to mention the mask. Yes i set it to 255.255.255.0 and the Gateway to 0.0.0.0. On the PLC an Ethernet driver is already configured. There is already one PC connected to the PLC. do i have to configure the Ethernet driver on my PC too?

Hello, i want to connect my PC to the PLC(RSLogix5561)  over TCP/IP. In rslinx the Ethernet driver are configured. My PLC IP Adresse is 192.168.1.100 and my PC Adresse is 192.168.1.105. From my PC i can successfully ping the PLC IP Adresse, but from the PLC i can't see my PC. And it does'nt schow in RSlinx. Is there anything i am missing?

Thanks you for your Reply. Can i generate high frequency(100Hz) and smooth sine wave with this approach ?

You are Right Michael. I notice that in practice  Control Engineers usualy do empirical adjustments, wich is fine. My plan is to design an Iterative learning Control algorithm for the existing Control system. The point to have a Bode plot, is to analyse the stability of the System. That is, to know, at wich frequency my System goes instabil. Knowing that i can design a filter at a desired cuttoff frequency for my learning Control.

yess thanks Michael by a PID loop in a PLC. LabVIEW use the transfert function of the plant. If i had the transfert function, i could easily plot it on MATLAB too or other Simulation Software.

what is wrong with a linear Motor (controlled by a plc)  driving a pump?. OK Forget About the sine wave and all the above stuff if you want. My Question is how do i perform frequency reponse  test on a closed loop System controled by a plc ?

Yes your assumption is Right Boblfoot. The Motor is a linear Motor. AS i said to Michael, i have a closed loop System controlled by a plc with a PID Controller. So i just Need to perform frequency test on it. I just want to know if  i can create sin wave with different frequency with logix or i Need an extra Signal Generator.

The Pump is already controlled with a PID-Controller implemented in Ladder Diagramm in the PLC. I Need to measure frequency Response on the closed System. To do so, the Input of the System has to be a sine wave with different frequency in order to excit the Systems and record the Responses. With this Information i can produce the Bode Diagramm (Gain and Phase of the Systems ).