Jeff-Sayto Posted March 20, 2022 Report Share Posted March 20, 2022 Hi everyone. I have tried to communicate with a MYCOM compressor that has a MAYEKAWA controller which in the manual says that it allows RS485 communication, I have been trying for 3 days without success. The MAYEKAWA controller detects the requests made by the V1210 but when returning the information it arrives with a 5 in the message status. Quote Link to comment Share on other sites More sharing options...
MVP 2023 Joe Tauser Posted March 20, 2022 MVP 2023 Report Share Posted March 20, 2022 RS485 describes a hardware and wiring standard. Unitronics typically uses this to send Modbus protocol commands. Your controller must have Modbus capability for this to work. Can you post a link to your controller manual? Joe T. 1 Quote Link to comment Share on other sites More sharing options...
Jeff-Sayto Posted March 20, 2022 Author Report Share Posted March 20, 2022 Hi Joe T, thanks for your quick response. The MAYEKAWA processor manual link is here https://qdoc.tips/cp4-mycom-manual-pdf-free.html. According to the document, it is possible, but I get an error when doing the holding registers. Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 20, 2022 MVP 2023 Report Share Posted March 20, 2022 Hi, i do not find full manual, but as i know - you must use correct wiring (four wire half duplex used) for MODBUS communication and set correct communication channel in panel setup menu. I find modbus manual for new type of panels https://mayekawa.com/americas/mna/downloads/pdf/CP Integration/MYPRO Touchplus/DEVICELISTMYPROTOUCHAREA.pdf https://mayekawa.com/americas/mna/downloads/pdf/CP Integration/MYPRO Touch/MYPROTOUCHDeviceListMYPROTouchAreaManual.pdf but you must use appropriate for your panel. 1 Quote Link to comment Share on other sites More sharing options...
AlexUT Posted March 20, 2022 Report Share Posted March 20, 2022 I found full manual. *It is not real file name. Original file name being very complex. Hope it will be helpful. B.R. Mayekava MYPRO-CPIV_Manual-pdf-free.pdf 1 1 Quote Link to comment Share on other sites More sharing options...
MVP 2023 Ausman Posted March 20, 2022 MVP 2023 Report Share Posted March 20, 2022 The manual makes reference to onboard termination resistors which I assume are set ok, and are also done correctly at the plc end. I've said it before and will say it again, it is so much easier to do initial modbus work with the PC, to ascertain correct numbering requests and all possibilities available. Don't forget Visilogic's numbering system can differ by 1. cheers, Aus 1 Quote Link to comment Share on other sites More sharing options...
Jeff-Sayto Posted March 21, 2022 Author Report Share Posted March 21, 2022 Hello, thank you very much for your prompt response Gentlemen. I want to thank AlexUT for providing the correct MAYEKAWA CP IV controller manual. According to wiring it should be like the first image: The data flow should be as follows but I am not very clear about this form of data flow, could you explain to me how to do it? The number references should be the following, but I have called them decimal or hexadecimal but without success. If you want to see the manual I will leave it here, again thanking AlexUT. 488091769_MayekavaMYPRO-CPIV_Manual-pdf-free.pdf Quote Link to comment Share on other sites More sharing options...
Jeff-Sayto Posted March 21, 2022 Author Report Share Posted March 21, 2022 Hi Ausman, Sorry for the mishandling of the page I did not want to report your comment. I reported it without realizing it, I'm very sorry. I was asking him how to do the communication work first on the PC. Sorry mr Ausman😔 Quote Link to comment Share on other sites More sharing options...
MVP 2023 Ausman Posted March 21, 2022 MVP 2023 Report Share Posted March 21, 2022 No worries at all. I'm suggesting you use something like Modbus Poll or a similar program, which lets you easily communicate with the remote device to find what works and what doesn't. Once you find exactly the best way to do things by using the PC, you can easily translate that method(s) into PLC use. Trying to do it in the first place just using the PLC is very cumbersome. Am I correct in assuming that you now have comms working ok, but are having trouble with the data layout? cheers, Aus Quote Link to comment Share on other sites More sharing options...
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