Energy Management or Building Automation

I would like to build a system using my home as the pilot project. I have a thermostat that uses Modbus for communications with 8 analog inputs and several relay and analog outputs. I would like to log temperatures, voltage and current to start.

I'm knowledgeable in HVAC but new to PLC and Modbus. Is there any software with HVAC logic for modbus/plc? Any suggestions?

My suggestion is to look for something designed for building automation control. Being familiar with HVAC, you may have been exposed to them. Automated Logic is one vendor. Good luck, and keep us posted on your results. This is an intrigueing home project that has already exploded in the commercial setting.

I need more information from you on the purpose of the project.

I looked into using PLC for building control but found the much lower cost of BMS type system make it a hard sell unless you are in some type of high value production facility.

If you just want to have more control on your home's thermostate. google "IP thermostat" and you will find some options there.

The company I work for installs DDC controls primarily for energy management. I've run across a thermostat from China for under $100. that would cost $600.+ if my company sold it. 8 AI's and 7 DO's, expandable, communicates with modbus.I would like to use this t-stat and plc as the basis to control small commercial energy management projects, but don't know anything about Modbus. I purchased the plc book from this site, but would like to shorten the learning time.