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Need Help Interpreting MODBUS Documentation
Problem finding correct address in equipment documentation
By JohnMartin on 20 June, 2019 - 7:48 pm

Hi,

I have an Afore inverter connected to my solar panels. The inverter has wifi/rs485 connection.

I have been in contact with an Afore technician and have gotten the RS485 communication documentation. Sadly, it is somewhat over my head.

I'm not too familiar with MODBUS. Have just recently gotten my home ventilation to talk to homeseer.

But this documentation does not contain the same information. I'm having problems finding out what address I should use to read the data from the inverter.

Is there anyone that could have a look at this and maybe assist me?

For my ventilation, the documentation clearly stated the address to be used for the different data, but not for the inverter.

See section 3.3.2 https://ufile.io/f7rttgai

By JohnMartin on 20 June, 2019 - 11:17 pm

Updated link to documentation:
https://drive.google.com/file/d/1bg9tbUqS1WnROl79ycRvPjXLE9wiIQ4y/view?usp=sharing

>I'm not too familiar with MODBUS.

That won'€™t make any difference because the documented protocol is not Modbus. It bears some similarities, but a Modbus RTU master will never get a reply message from your slave inverter because the inverter protocol is not Modbus.

Yes, Modbus and this protocol both operate over an RS-485 bus/network, but the rules for communicating, the protocol, are not identical and to communicate, they both have to play by the same rules, the same protocol.

If the inverter vendor does not provide a software "€˜master"€™ intended to communicate with the inverter, you'll have to write/code your own driver and software.

Welcome to the world of proprietary industrial communications.