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Meeg

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  1. So if I understand you correct: - Data Tables are not stored in the SD card before the "store to file" command is executed. - "load from file" can be used at initialisation (after Power failure) in order to recover the stored values?
  2. I have a question regarding Data Tables and the "retained" option. I have some rather large tables, to big to have them all as retained. But I still want to keep the values in case of Power failure. In your help function it is noted that Data Tables reside the SD card.. Still there is an option if they should be "retained". But is it not retained anyway if it is stored in the SD? Will they always be recovered from the SD card at power up? Or does it have to be done using the "store to file" and "load from file" functions? In my application is acceptable to store the tables periodically
  3. Hello, And thanks to both of you for good answers. You are obviously a lot more experienced with Modbus than I am. Unfortunately the sensors can only communicate at 9600baud. Trying aperiodic is probably a good idea. But maybe using a timer rather than the session Counter? Refer 2) below, the session counter will count even if the variable is not updated with a new value. You are reffering to UART, CPU, or ladder execution times to slow things down. To me this sounds strange as it must also be able to handle much higher baudrates and amounts of data? So what I still do
  4. Hello I am using modbus RTU Reading two sensors. Modbus ID = 1 & 2 respectively. From each sensor i read two values, one 16bit and one 32bit float. Baudrate = 9600. When I activate communication using "Active periodic" bit any one of the sensors (only) I can set my update interval at 100ms without having failures. The "funny" things occur when when i activate both: If I set my update interval at 400ms: It updates values from both sensor for a few Seconds (at 400ms rate), then it stops completely updating the reading/values from ID2. But the "success" Counter continues
  5. Thanks for helping ORS! I only had the the old example projects downloaded (from V1.15). With the help from the Advanced commands in V1.19 I was able to see that the commands was OK. It turned out to be a hardware problem. The sensor (ECD DS80 conductivity sensor) was not 100% rs485 compatible so I had to turn of the resistors on the CPU and use a 1k resistor instead. By the way, do you know why it is 2 resistors on the CPU? And what size and how are the resistors connected? The CPU manual does not give any details and normally only one 150ohm is used for cable termination
  6. Hello. I have the same question. Is there any detailed description somewhere yet? My problem is Reading 2 values from a sensor. Using a Modbus simulator it Works fine from my PC, but not from the PLC. The communication from my PC is shown in enclosed file. When I use the "Modbus Read Builder" it seems that the "request buffer" is the same as TX in the enclosed document. But I am not sure if (or how) to use the "Read parser" to get the answer? Thanks for an excelent software! Regards Anders Meeg Modbus to DS80.docx
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