Patko Posted March 14, 2022 Report Share Posted March 14, 2022 I use PLC unitronics US10-B10-T42 and a frequency converter from NORD. The frequency converter contains an absolute encoder for positioning. The connection is via MODBUS RS485. I thought it would be easier but I can't get advice on how to get the necessary command from the PLC to the frequency converter. What format should it be. I've seen that a periodic or aperiodic coil / register must be used but I don't know what it should look like in a ladder, what all has to be there. I also looked at the examples Unitronics Unilogic Examples \ UniLogic Examples_V1.30 Rev 52 \ Communications \ MODBUS RS485 \ UniStream_070_Modbus_RS485_Master_Aperiodic but I don't know if this is exactly what I need. If someone was dealing with such a communication and sent me an example for inspiration or could help me, I would be grateful. well thank you Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 14, 2022 MVP 2023 Report Share Posted March 14, 2022 Nord frequency converters have a specific command structure for control. Some settings are configured only from the local control panel. Please send the full marking (nameplate fotos) of NORD frequency converter and the type of motor and encoder. Quote Link to comment Share on other sites More sharing options...
Patko Posted March 14, 2022 Author Report Share Posted March 14, 2022 For testing I have borrowed a test station that has a frequency converter and a motor (the label is in the pictures test_Station). We will use two frequency converters and two motors for the application itself, on one of them there will be an absolute sensor (configuration in pictures NORD1,2,3,4,5) Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 14, 2022 MVP 2023 Report Share Posted March 14, 2022 Do you have installed NORD commisioning software and run connection to VFD? Is it VFD control panel present on your test station? Quote Link to comment Share on other sites More sharing options...
Patko Posted March 14, 2022 Author Report Share Posted March 14, 2022 Do you mean NORDCON software? Yes, I have, but he doesn't want to connect me to VFD, I'm still trying to know if I have the wrong cable or what's the problem. Yes, I have a test panel for VFD. Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 14, 2022 MVP 2023 Report Share Posted March 14, 2022 Unfortunately, now I do not have the opportunity to tell you in more detail. I'll try to do it later. However, you should now try to read the instructions and start the connection of the NORDCON program with the frequency converter. This is important for further connection to the Unistream. Quote Link to comment Share on other sites More sharing options...
Patko Posted March 14, 2022 Author Report Share Posted March 14, 2022 All right, I'll try to start a VFD connection with the NORDCON software, if I manage, I'll write here. Thank you. Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 14, 2022 MVP 2023 Report Share Posted March 14, 2022 Hi, i look for some manuals and find https://www.nord.com/media/documents/bw/bu0050_gb_3111.pdf As i see MODBUS RTU is supported on SK540E and bove - please see p.61. USS protocol implemented on SK 530E is like Siemens Profibus. Not supported by Unistream. You must ask NORD support about 530E communication, but i think only CANopen is possible to use with Unistream. Quote Link to comment Share on other sites More sharing options...
Patko Posted March 14, 2022 Author Report Share Posted March 14, 2022 Yes, you are right according to this pdf and MODBUS RTU is only supported from version SK540E. : /. In this case, should I buy another module on UniStream or does it need to be solved on the NORD side? Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 14, 2022 MVP 2023 Report Share Posted March 14, 2022 Unistream side not support Profibus. You can use one of embedded to Unisream protocol, please find all possible on Unitronics site https://www.unitronicsplc.com/unistream-series-unistream7/#1449515771593-63d974b6-05ac1451602511853 Or try to find some protocol converter But i think change inverter to the upper model needed. I do not know about your application. Maybe use Unitronics Servo product is the best way. Quote Link to comment Share on other sites More sharing options...
Patko Posted March 14, 2022 Author Report Share Posted March 14, 2022 Tomorrow I will take over with the sales representative and technical support from the Nord, because they assured me that there will be no problem with MODBUS RTU and it seems that it will be. Engines with selected VFDs are already ordered but it probably won't work ... Thanks for the advice, I'll let you know what the solution was. If necessary, do you have an example of how to do it to communicate properly? Quote Link to comment Share on other sites More sharing options...
Patko Posted March 15, 2022 Author Report Share Posted March 15, 2022 I called with technical support from NORD and currently it is so that all VFDs can communicate via MODBUS RTU. This PDF is old, and it is true that at that time only VFD versions 540E and above could do it, but then they updated the processors and all VFDs can do it. Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 15, 2022 MVP 2023 Report Share Posted March 15, 2022 Great, than you can find info about Modbus communication in this PDF. Please post some info about needed control algo and maybe we can find solution for your system. P.S. Thanks for info about NORD drive modbus update. I found this problem in the past (500 series) and must migrate to Lenze drive and CANopen. Quote Link to comment Share on other sites More sharing options...
Patko Posted March 16, 2022 Author Report Share Posted March 16, 2022 We are going to make an automated rack (warehouse) with 12 positions. We will have two engines and two VFDs. One motor will control the "elevator" up and down and the other motor will pull and slide the drawer. The motor for controlling the "elevator" will have an absolute sensor that will position the individual positions. Everything will be controlled via VFD, but the PLC must be the master through which the position is entered, and through the ladder and sensors it will automatically select whether to pull or slide the drawer and thus send a command whether the motor should go backwards or forwards. You are welcome, I was happy to provide this information. Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 16, 2022 MVP 2023 Report Share Posted March 16, 2022 I try to find info about your absolute encoder with embedded CANopen. https://www.nord.com/media/documents/bw/ag_0100_en_3216_screen.pdf In this manual present CANopen encoder feedback commisioning and on p.69 present info about possible preprogrammed fixed position (63 for 530E VFD). I think best way to control this application is operate with preprogrammed in VFD fixed positions. Then in PLC you can use 4 bit binary coding for 16 absolute position changover. In this case no modbus connection needed. One problem - find way (parameters on VFD) for fixed position program and switch via VFD logic input and program logic VFD outputs - in position, VFD ready (OK). P.S Yes you can program and change current positions via fieldbus (CANopen, MODBUS). But it is not easy way. p.p.s Second VFD positioning must be controled with two proximity sensors? Quote Link to comment Share on other sites More sharing options...
Patko Posted March 17, 2022 Author Report Share Posted March 17, 2022 When I spoke with technical support from NORD, they told me that they would set the exact positions through VFD and according to the agreement I would just send the value of the position. For example, position 2 will be in drive 2650 but I will only send number 2 from the PLC to the drive. Only one position will be positions 1-12. When the drawer is pulled out, the motor stop (positioning) is controlled by inductive sensors. Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 17, 2022 MVP 2023 Report Share Posted March 17, 2022 1 hour ago, Patko said: 2 will be in drive 2650 but I will only send number 2 from the PLC to the drive Yes, this is exactly the option I was talking about. In practice, the position number can be selected by inputs or by communication network. As I mentioned above, the signals that need to be transmitted from the frequency converter to the PLC are "movement completed in the desired position", "frequency converter in good condition", if necessary, you can transmit more errors of the frequency converter. 1 Quote Link to comment Share on other sites More sharing options...
Patko Posted March 25, 2022 Author Report Share Posted March 25, 2022 Hello kratmel, I finally have the right VFD. But I can't start communication. status is 3, which indicates an error. Through NORDCON I set the source of the control word USS, baud rate I have set the same in VFD and in PLC. Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 25, 2022 MVP 2023 Report Share Posted March 25, 2022 Hi, USS is not Modbus.... But as i see on p.61 if modbus is present - VFD select needed protocol in auto mode (it is strange USS must be selected). I think you must try to do RS485 modbus connection via PC and standard modbus software (like Qmodbus or another free modbus soft). Then you can see is it communication work and how VFD respond to your command. Then you can try to do all possible mode. The frequency inverter can process 2 versions of the Modbus protocol. 1. Communication via Bus IOs: If the frequency inverter is to be accessed via Bus IO Bits, the functions must be assigned in parameters (P480) and (P481). The source for the control word and the setpoints (P509/P510) must be set to "Control terminals". (For details: see "Coil list") 2. Process data communication: If process data is to be exchanged or parameters changed, the source for the control word and the setpoints (P509/P510) must be set to "USS". The definition of the parameters is made in the parameters (P543) to (P548). (For details: see "Process data") Quote Link to comment Share on other sites More sharing options...
Patko Posted March 25, 2022 Author Report Share Posted March 25, 2022 I have it in parameter 509 set to USS. If you have time, can't we connect through Teamwiever or Anydesk? Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted March 25, 2022 MVP 2023 Report Share Posted March 25, 2022 Some quastions: 1) PC to RS485 converter present on table? 2) Modbus evaluation software on PC is installed? I do not know is it Modbus option present in your VFD. You say On 3/15/2022 at 9:46 AM, Patko said: I called with technical support from NORD and currently it is so that all VFDs can communicate via MODBUS RTU. This PDF is old, and it is true that at that time only VFD versions 540E and above could do it, but then they updated the processors and all VFDs can do it. But if this option is enabled - NORD must declare from what SW version for 530E this option is enabled. I do not find any document about it.... p.s. I can run Anydesk... post me about it in PM. Quote Link to comment Share on other sites More sharing options...
Patko Posted March 25, 2022 Author Report Share Posted March 25, 2022 1. Yes I have a PC and VFD connection, via USB (pc) -RS232-RJ12 (vfd). I use NORDCON 2.8.6.1 software 2. Yes, I downloaded and installed the QModBus 0.2.1 software 3. I asked the support who lent me the VFD, I will call him again to confirm it. 4. VFDs with a new processor all have the option of communication via MODBUS RTU I sent you anydesk in a private message. Thank you Quote Link to comment Share on other sites More sharing options...
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