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Modbus frame sent to slave - strange size

4 posts in this topic

Hi,

I want to sent simply frame using FB mady by JPV from Omron France. It should send just frame  01030FA60002273C  to slave #1

When I check Multiway - it seems that frame is OK, but slave no reply.

I checked different soft to monitor serial port and frame looks different - some bytes are sent twice. 

I attached   screenshot and you can see the difference - Can you explain why it happened. Both frame I got when I set W30.0 in PLC and I saw just one blink LED

Hmm

I also attached screenshot from my serail port configuration. I tried also diiferent set of CP1W-CIF11 dip switches, but the same effect.


Any clue???

thanks in advance

 

 

 

  

 

 

 

 

multiway_1.jpg

multiway_2.jpg

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Check with ModScan Software with data frame monitor to check pattern of data frame then compare with PLC Modbus Data Frame if it same it should be connect to slave device.

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 Can you send via multi-way & get a response?

 

my standard goto is to test with multi-way, both as a master & a slave for verification.

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I sent some frame from multiway as I attached and I got some reply but strange is that I get reply only if I sent frame and exktra "0000".

If I send just a frame I get no response.

I already sent some question to device producer, but not yet answer - just reply that device support standard modbus RTU

Maybe you could explain that "0000", 

 

 

lumel_rs485.jpg

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