alexandre_poliplanta Posted February 15, 2021 Report Share Posted February 15, 2021 hi every one. i try put one more device in my modbus rtu network. this device can communicate very well with my pc over one serial port 485. but if i put this device on the last slot of my net work, he canot work... the list with the status code in help file have explanation until the value -7. but i have the status value -11 or some time -12. please help me find tis problem Quote Link to comment Share on other sites More sharing options...
MVP 2023 Joe Tauser Posted February 16, 2021 MVP 2023 Report Share Posted February 16, 2021 3 hours ago, alexandre_poliplanta said: but if i put this device on the last slot of my net work, he canot work... Please explain this statement in more detail. What is the node address of the device? What is the node address of the pc? What is the node address of the PLC? It would be helpful if you post a link to the device type and attach your PLC program to a post. Joe T. Quote Link to comment Share on other sites More sharing options...
alexandre_poliplanta Posted February 16, 2021 Author Report Share Posted February 16, 2021 ok then... in config we can see the parameter of the modbus rtu network in use. in config specs we can see the hardware in use. in config status we can see the data over this global network data online. *the value of the status is 3, i guess it is a problem. * the tag tensaoPeletStatus the value is -11 and some time this value is 13 - these values are some kind of error code but we cant have the intire errorcode list... in config weg address we can see some registers input avaliable and the most import,,, the type of format data FLOAT... and de clp unitronics will work with format REAL. weg tel me some thing about the format float in use... this float are in format float point IEEE 754. can this plc unitronics work with this format data? when a try cath othes values for test only... is the registers are format int, every gone well. but when a try change for other values ( float) i cath this error code. Quote Link to comment Share on other sites More sharing options...
alexandre_poliplanta Posted February 16, 2021 Author Report Share Posted February 16, 2021 look item 12.4 input. sheet 65 i need the corrent value WEG-manual-MMW02-pt.pdf Quote Link to comment Share on other sites More sharing options...
ORSO2001 Posted February 17, 2021 Report Share Posted February 17, 2021 dear alexandre_poliplante, to read the value of "corrente media [A]" are you point the register 5 (endereco long) or 10 (endereco short)? I think that you have to point the register 10 and read 2 contiguous registeres...so 10 and 11. Quote Link to comment Share on other sites More sharing options...
alexandre_poliplanta Posted February 17, 2021 Author Report Share Posted February 17, 2021 hi!! i try read every single combination. try read register 5 and after the falure i try read register 10. try using address long and try again using adress short. but not worked. Quote Link to comment Share on other sites More sharing options...
ORSO2001 Posted February 17, 2021 Report Share Posted February 17, 2021 hi...can you share how your slave are configured as registers read/write and also how you call the modbus function in the ladder? Quote Link to comment Share on other sites More sharing options...
alexandre_poliplanta Posted February 17, 2021 Author Report Share Posted February 17, 2021 yes... i can... the slave are configurade as the followed way: remote slave ID: 11 baud rate: 9600 Data bit: 8 Paraty: none Stop bit: 1 ------------------------------------------------------------------------------------------------------- this time i try use the adress register number 2... now i dont care this number... i need catch some value float. is it work i will chose the correct register float. Quote Link to comment Share on other sites More sharing options...
MVP 2023 Ausman Posted February 17, 2021 MVP 2023 Report Share Posted February 17, 2021 On 2/16/2021 at 7:56 AM, alexandre_poliplanta said: but if i put this device on the last slot of my net work, he canot work.. Does this mean you have connected it as the last thing on the loop? To me it sounds like you may have missed adjusting EOL resistors to suit the new configuration. You may have devices that include EOL on/off via dipswitches which will make it easy, or you need to physically change resistor(s) around. This would also explain why it works on the PC but not on the loop. RTU is very forgiving and will often run ok without resistors on a direct connection to the PC, but in the field things can be very different. cheers, Aus Quote Link to comment Share on other sites More sharing options...
alexandre_poliplanta Posted February 17, 2021 Author Report Share Posted February 17, 2021 I agree that in the field the scenario is much more complicated ... the point is that in the field, using the unitronic clp to read registers of the entire type, exactly from the same equipment provided by the company WEG. values of whole registers I can read with the clp. values of float registers I can't read from that same weg equipment. for some reason, the clp is unable to read float values. even when the register created in the clp is of the real type. Quote Link to comment Share on other sites More sharing options...
MVP 2023 Ausman Posted February 18, 2021 MVP 2023 Report Share Posted February 18, 2021 And the answer to my question is.....? Some types of requests can be handled by an incorrectly set up loop, whereas others won't work. This is not an airy fairy suggestion. I've had it happen to me when I've forgotten to change things correctly on additional devices being added to a loop. Lots of Head Smack at the time. So it's worth checking the physical wiring is totally correct. Quote Link to comment Share on other sites More sharing options...
alexandre_poliplanta Posted February 18, 2021 Author Report Share Posted February 18, 2021 I UNDERSTAND THE RELEVANCE OF THE REQUIREMENT FOR A GOOD ELECTRICAL CONNECTION. BUT AN INTERESTING THING ANSWERS. CLP GETS READ VALUES IN THE ENTIRE FORMAT THAT EXISTS IN THIS ENERGY METER FROM THE WEG COMPANY. CLP CANNOT READ VALUES IN THE FLOAT FORMAT OF THIS SAME ENERGY METER. IS IT POSSIBLE THAT THIS IS AN ELECTRICAL WIRING PROBLEM? A TYPE OF DATA CAN BE READ. OTHER TYPE OF DATA CANNOT READ. SAME EQUIPMENT, SAME SETUP AND SAME INSTALLATION. Quote Link to comment Share on other sites More sharing options...
MVP 2023 Joe Tauser Posted February 19, 2021 MVP 2023 Report Share Posted February 19, 2021 34 minutes ago, alexandre_poliplanta said: A TYPE OF DATA CAN BE READ. OTHER TYPE OF DATA CANNOT READ. This means your wiring, baud rate, and everything else physically is good. This is NOT a wiring problem. It's a Weg + Unitronics problem. Unitronics is probably choking on the byte order. We've had this conversation before about reading float values from energy meters via Modbus. Most of the time the energy meter manufacturer and Unitronics have different ideas about endianness. If you're not familiar with that term Google it up and you'll see pages that explain it much better than I can here. Take a look at this post: Try to read your floating point variables into a Buffer array tag that's at least four elements long per variable. Right now you're trying to get good read status. If you understand the content of the above post you'll be able to re-arrange the buffer elements into valid floating point data. If you're having trouble post your program with questions. Joe T. Quote Link to comment Share on other sites More sharing options...
alexandre_poliplanta Posted February 19, 2021 Author Report Share Posted February 19, 2021 Wonder! I had no experience with this feature using unitronic. I understand the endian issue reasonably well. This is very necessary. I didn't know how to use the buffer functionality, if you can get the bit packet and treat it, then I'll try to do that. Thank you, and whether it works or not, I will tell you. Quote Link to comment Share on other sites More sharing options...
alexandre_poliplanta Posted February 19, 2021 Author Report Share Posted February 19, 2021 It worked!! Very... Very... Very tks for every one!!! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.