Kojekude Posted April 13, 2012 Report Share Posted April 13, 2012 Hi, I'm new member. I'm programming first time in Visilogic and have some questions and observations: - what is the maximum number od HMI variables for V560? - if programm enter into modbus block, when results saves into memory and is modbus executes independent of programm scan? - I connected V560 with Omron inverters series JX via Modbus RTU (RS 485). It works only with V560 com port jumper settings RS485 with resistor although distance is only few meters. Quote Link to comment Share on other sites More sharing options...
Walkerok Posted April 13, 2012 Report Share Posted April 13, 2012 The maximum number of HMi screens is 1024 I am not sure what the maximum number of objects on a single screen are but I have had at least 100 or so on a screen before. The execution of modbus scans and the saving of data is NOT independent of program scans and will only execute once every program scan. The information that the PLC pics up through modbus is not saved until it correctly executes the modbus read block. The use of the termination resistor is neither good or bad. If it works with terminaltion then that will be fine to use. Generally a termination resistor is required for: 1) long 485 distances 2) The last item on a 485 network However I have found that periodically that termination can sometimes help in situations where ther is a lot of electrical noise (I am not sure why sometimes it does nothing) Keith Quote Link to comment Share on other sites More sharing options...
Emil Posted April 15, 2012 Report Share Posted April 15, 2012 Hi, 1. The number of variables per display in enhanced Vision models (V130/350/560/570/1040/1210) is not limited. 2. When controller faces Modbus command, it sends it immediatelly to the Slave. In this case "Function in progress" MB, defined in Modbus config module, rises to 1. During it's in 1 state, no other Modbus command can be executed. It's very good practice to add N.C. contact of "Function in progress" before each Modbus command! When reply from Slave arrives, Function in progress bit returns to 0.Accnolegment register rises by one. In this moment the new information from Slave is updating the defined registers. 3. If Omron Inverter has RS485 port, there is no any doubts that you need to set the jumpers in relevant port of V560 to RS485. Nothing else will work in this case and I hope you undersgtand this very well! Then - according to RS485 standard, at the end of the cable there must be set Termination! In V560, Termination is set via jumpers! It's not only resistor, is more advanced termination. It doesn't matter if the distance is 21.3cm or 847 meters - setting termination at the end of RS485 cable is a must! As I understand your project, you must set termin ation in side of V560 and in side of Omron driver. In V560 - I already mentioned - Termination needs to be set via jumpers. Please refer to the user manual of Omron driver for proper termination on their side! I hope this information will help. Quote Link to comment Share on other sites More sharing options...
Kojekude Posted April 15, 2012 Author Report Share Posted April 15, 2012 Thanx for help Quote Link to comment Share on other sites More sharing options...
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