question

betz avatar image
betz asked

MPPT with modbus

Hi,


I got a MPPT 150/85 MC4 hooked up, and I want to get data from it with modbus TCP.
My modbus connection works, as I can get other data, like register 840 etc,
but nothing from the PV system.

I tried registers:
- pv voltage (776)
- yield today (784)

But empty response. Am i missing something?

Modbus TCP
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2 Answers
wkirby avatar image
wkirby answered ·

Did you choose the correct Unit ID for the Solar Charger?
Find your Device Instance the one the Unit ID Mapping tab of the spreadsheet you can cross reference to get the correct Unit ID to request those registers from.

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Rob Howdle avatar image
Rob Howdle answered ·

Hi,

I presume you're connecting to the Venus GX via either VE.Direct1 or VE.Direct2 ports? If so, you will need to use Devive ID's as below:

VE.Direct1 - Device ID = 245 (Device Instance = 258)

VE.Direct2 - Device ID = 243 (Device Instance = 260)

Hope this helps.

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