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Setup guides → Hoymiles
Hoymiles microinverters
Read locally from a DTU-Pro or OpenDTU, per panel, with no cloud account and no polling limit. It sees production only, so you also need a grid meter.
This was tested against the vendor specifications but isn't running for Sunplug customers yet. If you experience any issue setting it up, reach out to [email protected] and I will work with you to iron out any issue.
You need the agent, and a DTU
The microinverters talk by radio to a DTU, which speaks Modbus TCP on port 502 on your network only, so Sunplug Agent must run in the house. It finds the DTU by sweeping the network. If the DTU is on another VLAN or behind NAT, pick Hoymiles from the manual list and enter its address; the port and unit id are editable there.
DTU-Lite doesn't speak Modbus — OpenDTU is the way round it
The above covers the DTU-Pro and DTU-Pro-S. The DTU-Lite is widely reported not to expose Modbus.
With a DTU-Lite or no DTU, use OpenDTU: open-source firmware for a
cheap ESP32 with the right radio, which talks to the microinverters directly.
The agent reads GET /api/livedata/status over HTTP, with no port
or unit id to set. If the sweep misses it, pick OpenDTU from the
manual list. It also sees production only.
What it can and cannot see
Surplus is production minus house use, and nothing in the array or the DTU measures house use. Rather than send every watt to the cars and buy the difference from the grid, Sunplug records production and tells you what is missing.
The usual answer: add a grid meter
Fit a Shelly EM or Pro 3EM at your supply point. The agent finds it on the same sweep and offers to pair it with the DTU.
The answer that costs nothing
In Settings, set Solar tracking to gross production. The cars charge on everything the panels make while the house draws from the grid, so you will buy some electricity. The allowance for the house beside it keeps a share of the array back.
Stuck? Email me.