Hi all, first post so apologies if I do this wrong. I’m trying to process data from Modbus and the values are mostly listed as int16. I’m seeing numbers but none of them correspond to the values I’m expecting. I was expecting something like:- outputvalueindecimal = parseInt(msg.payload); or out…

[image] UnborN: For SunSpec_ID 40001 it says its type is UINT32 but then goes on to say its a string "SunS" Both are correct. If you were to choose uint32 & then check the value, it would be 0x53756e53 - essentially the hexadecimal ASCII representation of "SunS" [image] UnborN: what does…

Goodness me. Looks like you’ve cracked it. Let me try those settings. Thanks for this. Yep, I set set it as you show and I get the correct results. The buffer carries on abd the problem is I have no accurate why of predicting the expected values so I need confidence in the method. The manual isn’t…

[image] Ianmidd: What does the offset mean.? Is it a count of bits As it parses a buffer, you need somewhere to start within that buffer, that is the offset. Essentially offset 0 means first byte in the buffer, offset 10 means the 10th byte in the buffer Again, the built in help in the side…

and if it helps to calculate the offset a bit more 1 modbus register = 16 bits = 2 bytes 32bit values need 4 bytes so you read 2 registers to 'decipher' them with Buffer parser depending on their type. Link to SunSpec manual . On page 16 they have the Register mappings

Making great progress now. Thanks for all the help. The Buffer Parse node automatically calculates the next offset correctly as you add the fields. Apart from the SolaEdge/SunSpec doc being wrong, the other problem (not an error) is that the node does not automatically change the Offset if the Type …

Hi Guys, again thanks so much for your help and encouragement. This is how far I have got now including the JSON output I am aiming for finally. There are two discrete calls to the ModBus (probably could be one in the end). nThe first deals with pages 16 & 17 of the SolarEdge/SunSpec document, the …

[Screenshot 2020-12-15 at 21.33.32]

Hi, you haven't copied the buffer, that's the data. If you set your debug to show full msg& expand it until you see the buffer & copy that (buffer is always bytes 0~255) [image] Ianmidd: Problem with group 1 - the last two field dont make sense to me Can you clarify that with a screenshot of…

First Group pages 16-17 of Spec Modbus Buffer {"payload":[21365,28243,1,65,21359,27745,29253,25703,25888,0,0,0,0,0,0,0,0,0,0,0,21317,13360,12336,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,12336,12339,11826,12600,13824,0,0,0,14150,12597,12342,17463,0,0,0,0,0,0,0,0,0,0,0,0,1,101,50,3984,3984,65535,65…

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Processing int16 values

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UnborN 15 December 2020 12:43 27

Yes .. very recently there was a discussion on the same brand of Solar inverters and the rest of the values (Power, Current etc ) have a scale factor SF that you need to convert with a formula in a Function node.

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Processing int16 values

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