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giannidegreve avatar image

How do I access the Modbus register list on multiplus-2 GX?

Hi all

I'am trying to control the multiplus-2-GX in labview using a compact Rio (NI). I found the modbus TCP register list, According to this file, the unit ID for the multiplus-2-GX is 275. But I'm not able to read or write any parameter using this unit ID. Is there someone having similar problems?

Thanks in advance.

Multiplus-IIModbus TCP
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2 Answers
wkirby avatar image
wkirby answered ·

I think you are looking at the device instance in column B. You need to look for the UnitID in column A, which is probably 228.

You can confirm the UnitID if you use the web browser to access the console with the GX IP address. In my example, my MultiPlus is on UnitID 238
Go: Settings -> Services -> ModbusTCP -> Modbus TCP services



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Thanks for the answer. But there al still some problems. The device instance in 275, so indeed I expect to fill in a unit ID of 228. But I still can't read the VE.bus registers (ex. input voltage phase 1 = register 3). On the other hand, I'm able to read registers with another unit ID (ex. unit ID=255 -> battery parameters over can-bus).

When i Go to Settings -> Services -> ModbusTCP, this is the screen I get.

So, unlike you, I'm not able to see the unit ID of the device.

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What version of Venus are you running? Settings -> Firmware

I have v2.58


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giannidegreve avatar image
giannidegreve answered ·

Yes, this might be the problem. I have V2.33. I will try again after I update the firmware. Thanks!

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